Bump version for 0.8.1

* main:
  Bump version for 0.8.0
  Remove images of the same name before pulling a new one
  Changed to a timeout
  Better language
  Switch to ruby-based retry

.github/workflows/ci.yml

@@ -0,0 +1,27 @@
+name: CI
+on: [push, pull_request]
+jobs:
+  tests:
+    strategy:
+      matrix:
+        ruby-version:
+          - "2.7"
+          - "3.1"
+          - "3.2"
+        continue-on-error: [false]
+
+    name: ${{ format('Tests (Ruby {0})', matrix.ruby-version) }}
+    runs-on: ubuntu-latest
+    continue-on-error: ${{ matrix.continue-on-error }}
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Install Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby-version }}
+          bundler-cache: true
+
+      - name: Run tests
+        run: bin/test

.gitignore

@@ -1,2 +1,4 @@
 .byebug_history
 *.gem
+coverage/*
+.DS_Store

Gemfile

@@ -1,9 +1,10 @@
 source 'https://rubygems.org'
 git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
-# Specify your gem's dependencies in importmap-rails.gemspec.
 gemspec
 
-group :test do
-  gem "byebug"
-end
+gem "debug"
+gem "mocha"
+gem "railties"
+gem "ed25519"
+gem "bcrypt_pbkdf"

Gemfile.lock

@@ -1,9 +1,12 @@
 PATH
   remote: .
   specs:
-    mrsk (0.0.1)
-      railties (>= 7.0.0)
+    mrsk (0.8.1)
+      activesupport (>= 7.0)
+      dotenv (~> 2.8)
       sshkit (~> 1.21)
+      thor (~> 1.2)
+      zeitwerk (~> 2.5)
 
 GEM
   remote: https://rubygems.org/
@@ -26,22 +29,36 @@ GEM
       i18n (>= 1.6, < 2)
       minitest (>= 5.1)
       tzinfo (~> 2.0)
+    bcrypt_pbkdf (1.1.0)
     builder (3.2.4)
-    byebug (11.1.3)
     concurrent-ruby (1.1.10)
     crass (1.0.6)
+    debug (1.7.1)
+      irb (>= 1.5.0)
+      reline (>= 0.3.1)
+    dotenv (2.8.1)
+    ed25519 (1.3.0)
     erubi (1.12.0)
     i18n (1.12.0)
       concurrent-ruby (~> 1.0)
+    io-console (0.6.0)
+    irb (1.6.2)
+      reline (>= 0.3.0)
     loofah (2.19.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     method_source (1.0.0)
     minitest (5.17.0)
+    mocha (2.0.2)
+      ruby2_keywords (>= 0.0.5)
     net-scp (4.0.0)
       net-ssh (>= 2.6.5, < 8.0.0)
     net-ssh (7.0.1)
-    nokogiri (1.13.10-arm64-darwin)
+    nokogiri (1.14.0-arm64-darwin)
+      racc (~> 1.4)
+    nokogiri (1.14.0-x86_64-darwin)
+      racc (~> 1.4)
+    nokogiri (1.14.0-x86_64-linux)
       racc (~> 1.4)
     racc (1.6.2)
     rack (2.2.5)
@@ -60,6 +77,9 @@ GEM
       thor (~> 1.0)
       zeitwerk (~> 2.5)
     rake (13.0.6)
+    reline (0.3.2)
+      io-console (~> 0.5)
+    ruby2_keywords (0.0.5)
     sshkit (1.21.3)
       net-scp (>= 1.1.2)
       net-ssh (>= 2.8.0)
@@ -74,11 +94,16 @@ PLATFORMS
   arm64-darwin-22
   x86_64-darwin-20
   x86_64-darwin-21
+  x86_64-darwin-22
   x86_64-linux
 
 DEPENDENCIES
-  byebug
+  bcrypt_pbkdf
+  debug
+  ed25519
+  mocha
   mrsk!
+  railties
 
 BUNDLED WITH
-   2.2.33
+   2.4.3

README.md

@@ -1,55 +1,505 @@
 # MRSK
 
-MRSK lets you do zero-downtime deploys of Rails apps packed as containers to any host running Docker. It uses the dynamic reverse-proxy Traefik to hold requests while the new application container is started and the old one is wound down. It works across multiple hosts at the same time, using SSHKit to execute commands.
+MRSK deploys web apps in containers to servers running Docker with zero downtime. It uses the dynamic reverse-proxy Traefik to hold requests while the new application container is started and the old one is stopped. It works seamlessly across multiple hosts, using SSHKit to execute commands. It was built for Rails applications, but works with any type of web app that can be bundled with Docker.
 
 ## Installation
 
-Create a configuration file for MRSK in `config/deploy.yml` that looks like this:
+Install MRSK globally with `gem install mrsk`. Then, inside your app directory, run `mrsk init` (or `mrsk init --bundle` within Rails apps where you want a bin/mrsk binstub). Now edit the new file `config/deploy.yml`. It could look as simple as this:
 
 ```yaml
-service: my-app
-image: name/my-app
+service: hey
+image: 37s/hey
 servers:
-  - xxx.xxx.xxx.xxx
-  - xxx.xxx.xxx.xxx
+  - 192.168.0.1
+  - 192.168.0.2
+registry:
+  username: registry-user-name
+  password:
+    - MRSK_REGISTRY_PASSWORD
 env:
-  DATABASE_URL: mysql2://username@localhost/database_name/
-  REDIS_URL: redis://host:6379/1
+  secret:
+    - RAILS_MASTER_KEY
 ```
 
-Then first login to the Docker Hub registry on the servers:
+Then edit your `.env` file to add your registry password as `MRSK_REGISTRY_PASSWORD` (and your `RAILS_MASTER_KEY` for production with a Rails app). 
+
+Now you're ready to deploy to the servers:
 
 ```
-rake mrsk:registry:login DOCKER_USER=name DOCKER_PASSWORD=pw
-```
-
-Now you're ready to deploy a multi-arch image (FIXME: currently you need to manually run `docker buildx create --use` once first):
-
-```
-rake mrsk:deploy
+mrsk deploy
 ```
 
 This will:
 
-1. Build the image using the standard Dockerfile in the root of the application.
-2. Push the image to the registry.
-3. Pull the image on all the servers.
-4. Ensure Traefik is running and accepting traffic on port 80.
-5. Stop any containers running a previous versions of the app.
-6. Start a new container with the version of the app that matches the current git version hash.
+1. Connect to the servers over SSH (using root by default, authenticated by your loaded ssh key)
+2. Install Docker on any server that might be missing it (using apt-get)
+3. Log into the registry both locally and remotely
+4. Build the image using the standard Dockerfile in the root of the application.
+5. Push the image to the registry.
+6. Pull the image from the registry on the servers.
+7. Ensure Traefik is running and accepting traffic on port 80.
+8. Ensure your app responds with `200 OK` to `GET /up`.
+9. Stop any containers running a previous versions of the app.
+10. Start a new container with the version of the app that matches the current git version hash.
+11. Prune unused images and stopped containers to ensure servers don't fill up.
 
-Voila! All the servers are now serving the app on port 80, and you're ready to put them behind a load balancer to serve live traffic.
+Voila! All the servers are now serving the app on port 80. If you're just running a single server, you're ready to go. If you're running multiple servers, you need to put a load balancer in front of them.
+
+## Vision
+
+In the past decade+, there's been an explosion in commercial offerings that make deploying web apps easier. Heroku kicked it off with an incredible offering that stayed ahead of the competition seemingly forever. These days we have excellent alternatives like Fly.io and Render. And hosted Kubernetes is making things easier too on AWS, GCP, Digital Ocean, and elsewhere. But these are all offerings that have you renting computers in the cloud at a premium. If you want to run on our own hardware, or even just have a clear migration path to do so, you need to carefully consider how locked in you get to these commercial platforms. Preferably before the bills swallow your business whole!
+
+MRSK seeks to bring the advance in ergonomics pioneered by these commercial offerings to deploying web apps anywhere. Whether that's low-cost cloud options without the managed-service markup from the likes of Digital Ocean, Hetzner, OVH, etc, or it's your own colocated metal. To MRSK, it's all the same. Feed the config file a list of IP addresses with vanilla Ubuntu servers that have seen no prep beyond an added SSH key, and you'll be running in literally minutes.
+
+This structure also gives you enormous portability. You can have your web app deployed on several clouds at ease like this. Or you can buy the baseline with your own hardware, then deploy to a cloud before a big seasonal spike to get more capacity. When you're not locked into a single provider from a tooling perspective, there's a lot of compelling options available.
+
+Ultimately, MRSK is meant to compress the complexity of going to production using open source tooling that isn't tied to any commercial offering. Not to zero, though. You're probably still better off with a fully managed service if basic Linux or Docker is still difficult, but from an early stage when those concepts are familiar.
+
+## Why not just run Capistrano, Kubernetes or Docker Swarm?
+
+MRSK basically is Capistrano for Containers, which allow us to use vanilla servers as the hosts. No need to ensure that the servers have just the right version of Ruby or other dependencies you need. That all lives in the Docker image now. You can boot a brand new Ubuntu (or whatever) server, add it to the deploy servers of MRSK, and it'll be auto-provisioned with Docker, and run right away. Docker's layer caching also allows for quicker deployments with less mucking about on the server. And the images built for MRSK can be used for CI or later introspection.
+
+Kubernetes is a beast. Running it yourself on your own hardware is not for the faint of heart. It's a fine option if you want to run on someone else's platform, either transparently [like Render](https://thenewstack.io/render-cloud-deployment-with-less-engineering/) or explicitly on AWS/GCP, but if you'd like the freedom to move between cloud and your own hardware, or even mix the two, MRSK is much simpler. You can see everything that's going on, it's just basic Docker commands being called.
+
+Docker Swarm is much simpler than Kubernetes, but it's still built on the same declarative model that uses state reconciliation. MRSK is intentionally designed to around imperative commands, like Capistrano.
+
+## Configuration
+
+### Using .env file to load required environment variables
+
+MRSK uses [dotenv](https://github.com/bkeepers/dotenv) to automatically load environment variables set in the `.env` file present in the application root. This file can be used to set variables like `MRSK_REGISTRY_PASSWORD` or database passwords. But for this reason you must ensure that .env files are not checked into Git or included in your Dockerfile! The format is just key-value like:
+
+```bash
+MRSK_REGISTRY_PASSWORD=pw
+DB_PASSWORD=secret123
+```
+
+### Using another registry than Docker Hub
+
+The default registry is Docker Hub, but you can change it using `registry/server`:
+
+```yaml
+registry:
+  server: registry.digitalocean.com
+  username: registry-user-name
+  password: <%= ENV.fetch("MRSK_REGISTRY_PASSWORD") %>
+```
+
+### Using a different SSH user than root
+
+The default SSH user is root, but you can change it using `ssh/user`:
+
+```yaml
+ssh:
+  user: app
+```
+
+### Using a proxy SSH host
+
+If you need to connect to server through a proxy host, you can use `ssh/proxy`:
+
+```yaml
+ssh:
+  proxy: "192.168.0.1" # defaults to root as the user
+```
+
+Or with specific user:
+
+```yaml
+ssh:
+  proxy: "app@192.168.0.1"
+```
+
+### Using env variables
+
+You can inject env variables into the app containers using `env`:
+
+```yaml
+env:
+  DATABASE_URL: mysql2://db1/hey_production/
+  REDIS_URL: redis://redis1:6379/1
+```
+
+### Using secret env variables
+
+If you have env variables that are secret, you can divide the `env` block into `clear` and `secret`:
+
+```yaml
+env:
+  clear:
+    DATABASE_URL: mysql2://db1/hey_production/
+    REDIS_URL: redis://redis1:6379/1
+  secret:
+    - DATABASE_PASSWORD
+    - REDIS_PASSWORD
+```
+
+The list of secret env variables will be expanded at run time from your local machine. So a reference to a secret `DATABASE_PASSWORD` will look for `ENV["DATABASE_PASSWORD"]` on the machine running MRSK. Just like with build secrets.
+
+If the referenced secret ENVs are missing, the configuration will be halted with a `KeyError` exception.
+
+Note: Marking an ENV as secret currently only redacts its value in the output for MRSK. The ENV is still injected in the clear into the container at runtime.
+
+### Using volumes
+
+You can add custom volumes into the app containers using `volumes`:
+
+```yaml
+volumes:
+  - "/local/path:/container/path"
+```
+
+### Using different roles for servers
+
+If your application uses separate hosts for running jobs or other roles beyond the default web running, you can specify these hosts in a dedicated role with a new entrypoint command like so:
+
+```yaml
+servers:
+  web:
+    - 192.168.0.1
+    - 192.168.0.2
+  job:
+    hosts:
+      - 192.168.0.3
+      - 192.168.0.4
+    cmd: bin/jobs
+```
+
+Note: Traefik will only by default be installed and run on the servers in the `web` role (and on all servers if no roles are defined). If you need Traefik on hosts in other roles than `web`, add `traefik: true`:
+
+```yaml
+servers:
+  web:
+    - 192.168.0.1
+    - 192.168.0.2
+  web2:
+    traefik: true
+    hosts:
+      - 192.168.0.3
+      - 192.168.0.4
+```
+
+### Using container labels
+
+You can specialize the default Traefik rules by setting labels on the containers that are being started:
+
+```
+labels:
+  traefik.http.routers.hey.rule: Host(\`app.hey.com\`)
+```
+
+Note: The escaped backticks are needed to ensure the rule is passed in correctly and not treated as command substitution by Bash!
+
+This allows you to run multiple applications on the same server sharing the same Traefik instance and port.
+See https://doc.traefik.io/traefik/routing/routers/#rule for a full list of available routing rules.
+
+The labels can also be applied on a per-role basis:
+
+```yaml
+servers:
+  web:
+    - 192.168.0.1
+    - 192.168.0.2
+  job:
+    hosts:
+      - 192.168.0.3
+      - 192.168.0.4
+    cmd: bin/jobs
+    labels:
+      my-label: "50"
+```
+
+### Using remote builder for native multi-arch
+
+If you're developing on ARM64 (like Apple Silicon), but you want to deploy on AMD64 (x86 64-bit), you can use multi-archecture images. By default, MRSK will setup a local buildx configuration that does this through QEMU emulation. But this can be quite slow, especially on the first build.
+
+If you want to speed up this process by using a remote AMD64 host to natively build the AMD64 part of the image, while natively building the ARM64 part locally, you can do so using builder options:
+
+```yaml
+builder:
+  local:
+    arch: arm64
+    host: unix:///Users/<%= `whoami`.strip %>/.docker/run/docker.sock
+  remote:
+    arch: amd64
+    host: ssh://root@192.168.0.1
+```
+
+Note: You must have Docker running on the remote host being used as a builder. This instance should only be shared for builds using the same registry and credentials.
+
+### Using remote builder for single-arch
+
+If you're developing on ARM64 (like Apple Silicon), want to deploy on AMD64 (x86 64-bit), but don't need to run the image locally (or on other ARM64 hosts), you can configure a remote builder that just targets AMD64. This is a bit faster than building with multi-arch, as there's nothing to build locally.
+
+```yaml
+builder:
+  remote:
+    arch: amd64
+    host: ssh://root@192.168.0.1
+```
+
+### Using native builder when multi-arch isn't needed
+
+If you're developing on the same architecture as the one you're deploying on, you can speed up the build by forgoing both multi-arch and remote building:
+
+```yaml
+builder:
+  multiarch: false
+```
+
+This is also a good option if you're running MRSK from a CI server that shares architecture with the deployment servers.
+
+### Using build secrets for new images
+
+Some images need a secret passed in during build time, like a GITHUB_TOKEN to give access to private gem repositories. This can be done by having the secret in ENV, then referencing it in the builder configuration:
+
+```yaml
+builder:
+  secrets:
+    - GITHUB_TOKEN
+```
+
+This build secret can then be referenced in the Dockerfile:
+
+```dockerfile
+# Copy Gemfiles
+COPY Gemfile Gemfile.lock ./
+
+# Install dependencies, including private repositories via access token (then remove bundle cache with exposed GITHUB_TOKEN)
+RUN --mount=type=secret,id=GITHUB_TOKEN \
+  BUNDLE_GITHUB__COM=x-access-token:$(cat /run/secrets/GITHUB_TOKEN) \
+  bundle install && \
+  rm -rf /usr/local/bundle/cache
+```
+
+### Using command arguments for Traefik
+
+You can customize the traefik command line:
+
+```yaml
+traefik:
+  args:
+    accesslog: true
+    accesslog.format: json
+```
+
+This will start the traefik container with `--accesslog=true accesslog.format=json`.
+
+### Configuring build args for new images
+
+Build arguments that aren't secret can also be configured:
+
+```yaml
+builder:
+  args:
+    RUBY_VERSION: 3.2.0
+```
+
+This build argument can then be used in the Dockerfile:
+
+```
+# Private repositories need an access token during the build
+ARG RUBY_VERSION
+FROM ruby:$RUBY_VERSION-slim as base
+```
+
+### Using accessories for database, cache, search services
+
+You can manage your accessory services via MRSK as well. The services will build off public images, and will not be automatically updated when you deploy:
+
+```yaml
+accessories:
+  mysql:
+    image: mysql:5.7
+    host: 1.1.1.3
+    port: 3306
+    env:
+      clear:
+        MYSQL_ROOT_HOST: '%'
+      secret:
+        - MYSQL_ROOT_PASSWORD
+    volumes:
+      - /var/lib/mysql:/var/lib/mysql
+  redis:
+    image: redis:latest
+    host: 1.1.1.4
+    port: "36379:6379"
+    volumes:
+      - /var/lib/redis:/data
+```
+
+Now run `mrsk accessory start mysql` to start the MySQL server on 1.1.1.3. See `mrsk accessory` for all the commands possible.
+
+### Using a generated .env file
+
+If you're using a centralized secret store, like 1Password, you can create `.env.erb` as a template which looks up the secrets. Example of a .env.erb file:
+
+```erb
+<% if (session_token = `op signin --account my-one-password-account --raw`.strip) != "" %># Generated by mrsk envify
+GITHUB_TOKEN=<%= `gh config get -h github.com oauth_token`.strip %>
+MRSK_REGISTRY_PASSWORD=<%= `op read "op://Vault/Docker Hub/password" -n --session  #{session_token}` %>
+RAILS_MASTER_KEY=<%= `op read "op://Vault/My App/RAILS_MASTER_SECRET" -n --session #{session_token}` %>
+MYSQL_ROOT_PASSWORD=<%= `op read "op://Vault/My App/MYSQL_ROOT_PASSWORD" -n --session #{session_token}` %>
+<% else raise ArgumentError, "Session token missing" end %>
+```
+
+This template can safely be checked into git. Then everyone deploying the app can run `mrsk envify` when they setup the app for the first time or passwords change to get the correct `.env` file.
+
+If you need separate env variables for different destinations, you can set them with `.env.destination.erb` for the template, which will generate `.env.staging` when run with `mrsk envify -d staging`.
+
+### Using audit broadcasts
+
+If you'd like to broadcast audits of deploys, rollbacks, etc to a chatroom or elsewhere, you can configure the `audit_broadcast_cmd` setting with the path to a bin file that will be passed the audit line as the first argument:
+
+```yaml
+audit_broadcast_cmd:
+  bin/audit_broadcast
+```
+
+The broadcast command could look something like:
+
+```bash
+#!/usr/bin/env bash
+curl -q -d content="[My App] ${1}" https://3.basecamp.com/XXXXX/integrations/XXXXX/buckets/XXXXX/chats/XXXXX/lines
+```
+
+That'll post a line like follows to a preconfigured chatbot in Basecamp:
+
+```
+[My App] [dhh] Rolled back to version d264c4e92470ad1bd18590f04466787262f605de
+```
+
+### Using custom healthcheck path or port
+
+MRSK defaults to checking the health of your application again `/up` on port 3000. You can tailor both with the `healthcheck` setting:
+
+```yaml
+healthcheck:
+  path: /healthz
+  port: 4000
+```
+
+This will ensure your application is configured with a traefik label for the healthcheck against `/healthz` and that the pre-deploy healthcheck that MRSK performs is done against the same path on port 4000.
+
+## Commands
+
+### Running commands on servers
+
+You can execute one-off commands on the servers:
+
+```bash
+# Runs command on all servers
+mrsk app exec 'ruby -v'
+App Host: 192.168.0.1
+ruby 3.1.3p185 (2022-11-24 revision 1a6b16756e) [x86_64-linux]
+
+App Host: 192.168.0.2
+ruby 3.1.3p185 (2022-11-24 revision 1a6b16756e) [x86_64-linux]
+
+# Runs command on primary server
+mrsk app exec --primary 'cat .ruby-version'
+App Host: 192.168.0.1
+3.1.3
+
+# Runs Rails command on all servers
+mrsk app exec 'bin/rails about'
+App Host: 192.168.0.1
+About your application's environment
+Rails version             7.1.0.alpha
+Ruby version              ruby 3.1.3p185 (2022-11-24 revision 1a6b16756e) [x86_64-linux]
+RubyGems version          3.3.26
+Rack version              2.2.5
+Middleware                ActionDispatch::HostAuthorization, Rack::Sendfile, ActionDispatch::Static, ActionDispatch::Executor, Rack::Runtime, Rack::MethodOverride, ActionDispatch::RequestId, ActionDispatch::RemoteIp, Rails::Rack::Logger, ActionDispatch::ShowExceptions, ActionDispatch::DebugExceptions, ActionDispatch::Callbacks, ActionDispatch::Cookies, ActionDispatch::Session::CookieStore, ActionDispatch::Flash, ActionDispatch::ContentSecurityPolicy::Middleware, ActionDispatch::PermissionsPolicy::Middleware, Rack::Head, Rack::ConditionalGet, Rack::ETag, Rack::TempfileReaper
+Application root          /rails
+Environment               production
+Database adapter          sqlite3
+Database schema version   20221231233303
+
+App Host: 192.168.0.2
+About your application's environment
+Rails version             7.1.0.alpha
+Ruby version              ruby 3.1.3p185 (2022-11-24 revision 1a6b16756e) [x86_64-linux]
+RubyGems version          3.3.26
+Rack version              2.2.5
+Middleware                ActionDispatch::HostAuthorization, Rack::Sendfile, ActionDispatch::Static, ActionDispatch::Executor, Rack::Runtime, Rack::MethodOverride, ActionDispatch::RequestId, ActionDispatch::RemoteIp, Rails::Rack::Logger, ActionDispatch::ShowExceptions, ActionDispatch::DebugExceptions, ActionDispatch::Callbacks, ActionDispatch::Cookies, ActionDispatch::Session::CookieStore, ActionDispatch::Flash, ActionDispatch::ContentSecurityPolicy::Middleware, ActionDispatch::PermissionsPolicy::Middleware, Rack::Head, Rack::ConditionalGet, Rack::ETag, Rack::TempfileReaper
+Application root          /rails
+Environment               production
+Database adapter          sqlite3
+Database schema version   20221231233303
+
+# Run Rails runner on primary server
+mrsk app exec -p 'bin/rails runner "puts Rails.application.config.time_zone"'
+UTC
+```
+
+### Running interactive commands over SSH
+
+You can run interactive commands, like a Rails console or a bash session, on a server (default is primary, use `--hosts` to connect to another):
+
+```bash
+# Starts a bash session in a new container made from the most recent app image
+mrsk app exec -i bash
+
+# Starts a bash session in the currently running container for the app
+mrsk app exec -i --reuse bash
+
+# Starts a Rails console in a new container made from the most recent app image
+mrsk app exec -i 'bin/rails console'
+```
+
+
+### Running details to show state of containers
+
+You can see the state of your servers by running `mrsk details`:
+
+```
+Traefik Host: 192.168.0.1
+CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS          PORTS                               NAMES
+6195b2a28c81   traefik   "/entrypoint.sh --pr…"   30 minutes ago   Up 19 minutes   0.0.0.0:80->80/tcp, :::80->80/tcp   traefik
+
+Traefik Host: 192.168.0.2
+CONTAINER ID   IMAGE     COMMAND                  CREATED          STATUS          PORTS                               NAMES
+de14a335d152   traefik   "/entrypoint.sh --pr…"   30 minutes ago   Up 19 minutes   0.0.0.0:80->80/tcp, :::80->80/tcp   traefik
+
+App Host: 192.168.0.1
+CONTAINER ID   IMAGE                                                                         COMMAND                  CREATED          STATUS          PORTS      NAMES
+badb1aa51db3   registry.digitalocean.com/user/app:6ef8a6a84c525b123c5245345a8483f86d05a123   "/rails/bin/docker-e…"   13 minutes ago   Up 13 minutes   3000/tcp   chat-6ef8a6a84c525b123c5245345a8483f86d05a123
+
+App Host: 192.168.0.2
+CONTAINER ID   IMAGE                                                                         COMMAND                  CREATED          STATUS          PORTS      NAMES
+1d3c91ed1f55   registry.digitalocean.com/user/app:6ef8a6a84c525b123c5245345a8483f86d05a123   "/rails/bin/docker-e…"   13 minutes ago   Up 13 minutes   3000/tcp   chat-6ef8a6a84c525b123c5245345a8483f86d05a123
+```
+
+You can also see just info for app containers with `mrsk app details` or just for Traefik with `mrsk traefik details`.
+
+### Running rollback to fix a bad deploy
+
+If you've discovered a bad deploy, you can quickly rollback by reactivating the old, paused container image. You can see what old containers are available for rollback by running `mrsk app containers`. It'll give you a presentation similar to `mrsk app details`, but include all the old containers as well. Showing something like this:
+
+```
+App Host: 192.168.0.1
+CONTAINER ID   IMAGE                                                                         COMMAND                  CREATED          STATUS                      PORTS      NAMES
+1d3c91ed1f51   registry.digitalocean.com/user/app:6ef8a6a84c525b123c5245345a8483f86d05a123   "/rails/bin/docker-e…"   19 minutes ago   Up 19 minutes               3000/tcp   chat-6ef8a6a84c525b123c5245345a8483f86d05a123
+539f26b28369   registry.digitalocean.com/user/app:e5d9d7c2b898289dfbc5f7f1334140d984eedae4   "/rails/bin/docker-e…"   31 minutes ago   Exited (1) 27 minutes ago              chat-e5d9d7c2b898289dfbc5f7f1334140d984eedae4
+
+App Host: 192.168.0.2
+CONTAINER ID   IMAGE                                                                         COMMAND                  CREATED          STATUS                      PORTS      NAMES
+badb1aa51db4   registry.digitalocean.com/user/app:6ef8a6a84c525b123c5245345a8483f86d05a123   "/rails/bin/docker-e…"   19 minutes ago   Up 19 minutes               3000/tcp   chat-6ef8a6a84c525b123c5245345a8483f86d05a123
+6f170d1172ae   registry.digitalocean.com/user/app:e5d9d7c2b898289dfbc5f7f1334140d984eedae4   "/rails/bin/docker-e…"   31 minutes ago   Exited (1) 27 minutes ago              chat-e5d9d7c2b898289dfbc5f7f1334140d984eedae4
+```
+
+From the example above, we can see that `e5d9d7c2b898289dfbc5f7f1334140d984eedae4` was the last version, so it's available as a rollback target. We can perform this rollback by running `mrsk rollback e5d9d7c2b898289dfbc5f7f1334140d984eedae4`. That'll stop `6ef8a6a84c525b123c5245345a8483f86d05a123` and then start `e5d9d7c2b898289dfbc5f7f1334140d984eedae4`. Because the old container is still available, this is very quick. Nothing to download from the registry.
+
+Note that by default old containers are pruned after 3 days when you run `mrsk deploy`.
+
+### Running removal to clean up servers
+
+If you wish to remove the entire application, including Traefik, containers, images, and registry session, you can run `mrsk remove`. This will leave the servers clean.
 
 ## Stage of development
 
-This is alpha software. Lots of stuff is missing. Here are some of the areas we seek to improve:
-
-- Use of other registries than Docker Hub
-- Adapterize commands to work with Podman and other container runners
-- Better flow for secrets and ENV
-- Possibly switching to a bin/mrsk command rather than raw rake
-- Integrate wirmth cloud CI pipelines
+This is alpha software. Lots of stuff is missing. Lots of stuff will keep moving around for a while.
 
 ## License
 
-Mrsk is released under the [MIT License](https://opensource.org/licenses/MIT).
+MRSK is released under the [MIT License](https://opensource.org/licenses/MIT).

bin/mrsk

@@ -0,0 +1,16 @@
+#!/usr/bin/env ruby
+
+# Prevent failures from being reported twice.
+Thread.report_on_exception = false
+
+require "mrsk"
+
+begin
+  Mrsk::Cli::Main.start(ARGV)
+rescue SSHKit::Runner::ExecuteError => e
+  puts "  \e[31mERROR (#{e.cause.class}): #{e.cause.message}\e[0m"
+  puts e.cause.backtrace if ENV["VERBOSE"]
+rescue => e
+  puts "  \e[31mERROR (#{e.class}): #{e.message}\e[0m"
+  puts e.backtrace if ENV["VERBOSE"]
+end

lib/mrsk.rb

@@ -1,8 +1,9 @@
 module Mrsk
 end
 
-require "mrsk/version"
-require "mrsk/engine"
+require "zeitwerk"
 
-require "mrsk/configuration"
-require "mrsk/commands"
+loader = Zeitwerk::Loader.for_gem
+loader.ignore("#{__dir__}/mrsk/sshkit_with_ext.rb")
+loader.setup
+loader.eager_load # We need all commands loaded.

lib/mrsk/cli.rb

@@ -0,0 +1,5 @@
+module Mrsk::Cli
+end
+
+# SSHKit uses instance eval, so we need a global const for ergonomics
+MRSK = Mrsk::Commander.new

lib/mrsk/cli/accessory.rb

@@ -0,0 +1,216 @@
+class Mrsk::Cli::Accessory < Mrsk::Cli::Base
+  desc "boot [NAME]", "Boot new accessory service on host (use NAME=all to boot all accessories)"
+  def boot(name)
+    if name == "all"
+      MRSK.accessory_names.each { |accessory_name| boot(accessory_name) }
+    else
+      with_accessory(name) do |accessory|
+        directories(name)
+        upload(name)
+
+        on(accessory.host) do
+          execute *MRSK.auditor.record("Booted #{name} accessory"), verbosity: :debug
+          execute *accessory.run
+        end
+
+        audit_broadcast "Booted accessory #{name}"
+      end
+    end
+  end
+
+  desc "upload [NAME]", "Upload accessory files to host", hide: true
+  def upload(name)
+    with_accessory(name) do |accessory|
+      on(accessory.host) do
+        accessory.files.each do |(local, remote)|
+          accessory.ensure_local_file_present(local)
+
+          execute *accessory.make_directory_for(remote)
+          upload! local, remote
+          execute :chmod, "755", remote
+        end
+      end
+    end
+  end
+
+  desc "directories [NAME]", "Create accessory directories on host", hide: true
+  def directories(name)
+    with_accessory(name) do |accessory|
+      on(accessory.host) do
+        accessory.directories.keys.each do |host_path|
+          execute *accessory.make_directory(host_path)
+        end
+      end
+    end
+  end
+
+  desc "reboot [NAME]", "Reboot existing accessory on host (stop container, remove container, start new container)"
+  def reboot(name)
+    with_accessory(name) do |accessory|
+      stop(name)
+      remove_container(name)
+      boot(name)
+    end
+  end
+
+  desc "start [NAME]", "Start existing accessory container on host"
+  def start(name)
+    with_accessory(name) do |accessory|
+      on(accessory.host) do
+        execute *MRSK.auditor.record("Started #{name} accessory"), verbosity: :debug
+        execute *accessory.start
+      end
+    end
+  end
+
+  desc "stop [NAME]", "Stop existing accessory container on host"
+  def stop(name)
+    with_accessory(name) do |accessory|
+      on(accessory.host) do
+        execute *MRSK.auditor.record("Stopped #{name} accessory"), verbosity: :debug
+        execute *accessory.stop, raise_on_non_zero_exit: false
+      end
+    end
+  end
+
+  desc "restart [NAME]", "Restart existing accessory container on host"
+  def restart(name)
+    with_accessory(name) do
+      stop(name)
+      start(name)
+    end
+  end
+
+  desc "details [NAME]", "Show details about accessory on host (use NAME=all to show all accessories)"
+  def details(name)
+    if name == "all"
+      MRSK.accessory_names.each { |accessory_name| details(accessory_name) }
+    else
+      with_accessory(name) do |accessory|
+        on(accessory.host) { puts capture_with_info(*accessory.info) }
+      end
+    end
+  end
+
+  desc "exec [NAME] [CMD]", "Execute a custom command on servers (use --help to show options)"
+  option :interactive, aliases: "-i", type: :boolean, default: false, desc: "Execute command over ssh for an interactive shell (use for console/bash)"
+  option :reuse, type: :boolean, default: false, desc: "Reuse currently running container instead of starting a new one"
+  def exec(name, cmd)
+    with_accessory(name) do |accessory|
+      case
+      when options[:interactive] && options[:reuse]
+        say "Launching interactive command with via SSH from existing container...", :magenta
+        run_locally { exec accessory.execute_in_existing_container_over_ssh(cmd) }
+
+      when options[:interactive]
+        say "Launching interactive command via SSH from new container...", :magenta
+        run_locally { exec accessory.execute_in_new_container_over_ssh(cmd) }
+
+      when options[:reuse]
+        say "Launching command from existing container...", :magenta
+        on(accessory.host) do
+          execute *MRSK.auditor.record("Executed cmd '#{cmd}' on #{name} accessory"), verbosity: :debug
+          capture_with_info(*accessory.execute_in_existing_container(cmd))
+        end
+
+      else
+        say "Launching command from new container...", :magenta
+        on(accessory.host) do
+          execute *MRSK.auditor.record("Executed cmd '#{cmd}' on #{name} accessory"), verbosity: :debug
+          capture_with_info(*accessory.execute_in_new_container(cmd))
+        end
+      end
+    end
+  end
+
+  desc "logs [NAME]", "Show log lines from accessory on host (use --help to show options)"
+  option :since, aliases: "-s", desc: "Show logs since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)"
+  option :lines, type: :numeric, aliases: "-n", desc: "Number of log lines to pull from each server"
+  option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
+  option :follow, aliases: "-f", desc: "Follow logs on primary server (or specific host set by --hosts)"
+  def logs(name)
+    with_accessory(name) do |accessory|
+      grep = options[:grep]
+
+      if options[:follow]
+        run_locally do
+          info "Following logs on #{accessory.host}..."
+          info accessory.follow_logs(grep: grep)
+          exec accessory.follow_logs(grep: grep)
+        end
+      else
+        since = options[:since]
+        lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
+
+        on(accessory.host) do
+          puts capture_with_info(*accessory.logs(since: since, lines: lines, grep: grep))
+        end
+      end
+    end
+  end
+
+  desc "remove [NAME]", "Remove accessory container and image from host (use NAME=all to remove all accessories)"
+  option :confirmed, aliases: "-y", type: :boolean, default: false, desc: "Proceed without confirmation question"
+  def remove(name)
+    if name == "all"
+      if options[:confirmed] || ask("This will remove all containers and images for all accessories. Are you sure?", limited_to: %w( y N ), default: "N") == "y"
+        MRSK.accessory_names.each { |accessory_name| remove(accessory_name) }
+      end
+    else
+      if options[:confirmed] || ask("This will remove all containers and images for #{name}. Are you sure?", limited_to: %w( y N ), default: "N") == "y"
+        with_accessory(name) do
+          stop(name)
+          remove_container(name)
+          remove_image(name)
+          remove_service_directory(name)
+        end
+      end
+    end
+  end
+
+  desc "remove_container [NAME]", "Remove accessory container from host", hide: true
+  def remove_container(name)
+    with_accessory(name) do |accessory|
+      on(accessory.host) do
+        execute *MRSK.auditor.record("Remove #{name} accessory container"), verbosity: :debug
+        execute *accessory.remove_container
+      end
+    end
+  end
+
+  desc "remove_image [NAME]", "Remove accessory image from host", hide: true
+  def remove_image(name)
+    with_accessory(name) do |accessory|
+      on(accessory.host) do
+        execute *MRSK.auditor.record("Removed #{name} accessory image"), verbosity: :debug
+        execute *accessory.remove_image
+      end
+    end
+  end
+
+  desc "remove_service_directory [NAME]", "Remove accessory directory used for uploaded files and data directories from host", hide: true
+  def remove_service_directory(name)
+    with_accessory(name) do |accessory|
+      on(accessory.host) do
+        execute *accessory.remove_service_directory
+      end
+    end
+  end
+
+  private
+    def with_accessory(name)
+      if accessory = MRSK.accessory(name)
+        yield accessory
+      else
+        error_on_missing_accessory(name)
+      end
+    end
+
+    def error_on_missing_accessory(name)
+      options = MRSK.accessory_names.presence
+
+      error \
+        "No accessory by the name of '#{name}'" +
+        (options ? " (options: #{options.to_sentence})" : "")
+    end
+end

lib/mrsk/cli/app.rb

@@ -0,0 +1,202 @@
+class Mrsk::Cli::App < Mrsk::Cli::Base
+  desc "boot", "Boot app on servers (or reboot app if already running)"
+  def boot
+    say "Get most recent version available as an image...", :magenta unless options[:version]
+    using_version(options[:version] || most_recent_version_available) do |version|
+      say "Start container with version #{version} (or reboot if already running)...", :magenta
+
+      MRSK.config.roles.each do |role|
+        on(role.hosts) do |host|
+          execute *MRSK.auditor.record("Booted app version #{version}"), verbosity: :debug
+
+          begin
+            execute *MRSK.app.stop, raise_on_non_zero_exit: false
+            execute *MRSK.app.run(role: role.name)
+          rescue SSHKit::Command::Failed => e
+            if e.message =~ /already in use/
+              error "Rebooting container with same version already deployed on #{host}"
+              execute *MRSK.auditor.record("Rebooted app version #{version}"), verbosity: :debug
+
+              execute *MRSK.app.remove_container(version: version)
+              execute *MRSK.app.run(role: role.name)
+            else
+              raise
+            end
+          end
+        end
+      end
+    end
+  end
+
+  desc "start", "Start existing app container on servers"
+  def start
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Started app version #{MRSK.version}"), verbosity: :debug
+      execute *MRSK.app.start, raise_on_non_zero_exit: false
+    end
+  end
+
+  desc "stop", "Stop app container on servers"
+  def stop
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Stopped app"), verbosity: :debug
+      execute *MRSK.app.stop, raise_on_non_zero_exit: false
+    end
+  end
+
+  # FIXME: Drop in favor of just containers?
+  desc "details", "Show details about app containers"
+  def details
+    on(MRSK.hosts) { |host| puts_by_host host, capture_with_info(*MRSK.app.info) }
+  end
+
+  desc "exec [CMD]", "Execute a custom command on servers (use --help to show options)"
+  option :interactive, aliases: "-i", type: :boolean, default: false, desc: "Execute command over ssh for an interactive shell (use for console/bash)"
+  option :reuse, type: :boolean, default: false, desc: "Reuse currently running container instead of starting a new one"
+  def exec(cmd)
+    case
+    when options[:interactive] && options[:reuse]
+      say "Get current version of running container...", :magenta unless options[:version]
+      using_version(options[:version] || current_running_version) do |version|
+        say "Launching interactive command with version #{version} via SSH from existing container on #{MRSK.primary_host}...", :magenta
+        run_locally { exec MRSK.app.execute_in_existing_container_over_ssh(cmd, host: MRSK.primary_host) }
+      end
+
+    when options[:interactive]
+      say "Get most recent version available as an image...", :magenta unless options[:version]
+      using_version(options[:version] || most_recent_version_available) do |version|
+        say "Launching interactive command with version #{version} via SSH from new container on #{MRSK.primary_host}...", :magenta
+        run_locally { exec MRSK.app.execute_in_new_container_over_ssh(cmd, host: MRSK.primary_host) }
+      end
+
+    when options[:reuse]
+      say "Get current version of running container...", :magenta unless options[:version]
+      using_version(options[:version] || current_running_version) do |version|
+        say "Launching command with version #{version} from existing container...", :magenta
+
+        on(MRSK.hosts) do |host|
+          execute *MRSK.auditor.record("Executed cmd '#{cmd}' on app version #{version}"), verbosity: :debug
+          puts_by_host host, capture_with_info(*MRSK.app.execute_in_existing_container(cmd))
+        end
+      end
+
+    else
+      say "Get most recent version available as an image...", :magenta unless options[:version]
+      using_version(options[:version] || most_recent_version_available) do |version|
+        say "Launching command with version #{version} from new container...", :magenta
+        on(MRSK.hosts) do |host|
+          execute *MRSK.auditor.record("Executed cmd '#{cmd}' on app version #{version}"), verbosity: :debug
+          puts_by_host host, capture_with_info(*MRSK.app.execute_in_new_container(cmd))
+        end
+      end
+    end
+  end
+
+  desc "containers", "Show app containers on servers"
+  def containers
+    on(MRSK.hosts) { |host| puts_by_host host, capture_with_info(*MRSK.app.list_containers) }
+  end
+
+  desc "images", "Show app images on servers"
+  def images
+    on(MRSK.hosts) { |host| puts_by_host host, capture_with_info(*MRSK.app.list_images) }
+  end
+
+  desc "logs", "Show log lines from app on servers (use --help to show options)"
+  option :since, aliases: "-s", desc: "Show lines since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)"
+  option :lines, type: :numeric, aliases: "-n", desc: "Number of lines to show from each server"
+  option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
+  option :follow, aliases: "-f", desc: "Follow log on primary server (or specific host set by --hosts)"
+  def logs
+    # FIXME: Catch when app containers aren't running
+
+    grep = options[:grep]
+
+    if options[:follow]
+      run_locally do
+        info "Following logs on #{MRSK.primary_host}..."
+        info MRSK.app.follow_logs(host: MRSK.primary_host, grep: grep)
+        exec MRSK.app.follow_logs(host: MRSK.primary_host, grep: grep)
+      end
+    else
+      since = options[:since]
+      lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
+
+      on(MRSK.hosts) do |host|
+        begin
+          puts_by_host host, capture_with_info(*MRSK.app.logs(since: since, lines: lines, grep: grep))
+        rescue SSHKit::Command::Failed
+          puts_by_host host, "Nothing found"
+        end
+      end
+    end
+  end
+
+  desc "remove", "Remove app containers and images from servers"
+  def remove
+    stop
+    remove_containers
+    remove_images
+  end
+
+  desc "remove_container [VERSION]", "Remove app container with given version from servers", hide: true
+  def remove_container(version)
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Removed app container with version #{version}"), verbosity: :debug
+      execute *MRSK.app.remove_container(version: version)
+    end
+  end
+
+  desc "remove_containers", "Remove all app containers from servers", hide: true
+  def remove_containers
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Removed all app containers"), verbosity: :debug
+      execute *MRSK.app.remove_containers
+    end
+  end
+
+  desc "remove_images", "Remove all app images from servers", hide: true
+  def remove_images
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Removed all app images"), verbosity: :debug
+      execute *MRSK.app.remove_images
+    end
+  end
+
+  desc "version", "Show app version currently running on servers"
+  def version
+    on(MRSK.hosts) { |host| puts_by_host host, capture_with_info(*MRSK.app.current_running_version).strip }
+  end
+
+  private
+    def using_version(new_version)
+      if new_version
+        begin
+          old_version = MRSK.config.version
+          MRSK.config.version = new_version
+          yield new_version
+        ensure
+          MRSK.config.version = old_version
+        end
+      else
+        yield MRSK.config.version
+      end
+    end
+
+    def most_recent_version_available(host: MRSK.primary_host)
+      version = nil
+      on(host) { version = capture_with_info(*MRSK.app.most_recent_version_from_available_images).strip }
+      
+      if version == "<none>"
+        raise "Most recent image available was not tagged with a version (returned <none>)"
+      else
+        version.presence
+      end
+    end
+
+    def current_running_version(host: MRSK.primary_host)
+      version = nil
+      on(host) { version = capture_with_info(*MRSK.app.current_running_version).strip }
+      version.presence
+    end
+end

lib/mrsk/cli/base.rb

@@ -0,0 +1,72 @@
+require "thor"
+require "dotenv"
+require "mrsk/sshkit_with_ext"
+
+module Mrsk::Cli
+  class Base < Thor
+    include SSHKit::DSL
+
+    def self.exit_on_failure?() true end
+
+    class_option :verbose, type: :boolean, aliases: "-v", desc: "Detailed logging"
+    class_option :quiet, type: :boolean, aliases: "-q", desc: "Minimal logging"
+
+    class_option :version, desc: "Run commands against a specific app version"
+
+    class_option :primary, type: :boolean, aliases: "-p", desc: "Run commands only on primary host instead of all"
+    class_option :hosts, aliases: "-h", desc: "Run commands on these hosts instead of all (separate by comma)"
+    class_option :roles, aliases: "-r", desc: "Run commands on these roles instead of all (separate by comma)"
+
+    class_option :config_file, aliases: "-c", default: "config/deploy.yml", desc: "Path to config file"
+    class_option :destination, aliases: "-d", desc: "Specify destination to be used for config file (staging -> deploy.staging.yml)"
+
+    def initialize(*)
+      super
+      load_envs
+      initialize_commander(options)
+    end
+
+    private
+      def load_envs
+        if destination = options[:destination]
+          Dotenv.load(".env.#{destination}", ".env")
+        else
+          Dotenv.load(".env")
+        end
+      end
+
+      def initialize_commander(options)
+        MRSK.tap do |commander|
+          commander.config_file = Pathname.new(File.expand_path(options[:config_file]))
+          commander.destination = options[:destination]
+          commander.version     = options[:version]
+
+          commander.specific_hosts    = options[:hosts]&.split(",")
+          commander.specific_roles    = options[:roles]&.split(",")
+          commander.specific_primary! if options[:primary]
+
+          if options[:verbose]
+            ENV["VERBOSE"] = "1" # For backtraces via cli/start
+            commander.verbosity = :debug
+          end
+
+          if options[:quiet]
+            commander.verbosity = :error
+          end
+        end
+      end
+
+      def print_runtime
+        started_at = Time.now
+        yield
+        return Time.now - started_at
+      ensure
+        runtime = Time.now - started_at
+        puts "  Finished all in #{sprintf("%.1f seconds", runtime)}"
+      end
+
+      def audit_broadcast(line)
+        run_locally { execute *MRSK.auditor.broadcast(line), verbosity: :debug }
+      end
+  end
+end

lib/mrsk/cli/build.rb

@@ -0,0 +1,70 @@
+class Mrsk::Cli::Build < Mrsk::Cli::Base
+  desc "deliver", "Build app and push app image to registry then pull image on servers"
+  def deliver
+    push
+    pull
+  end
+
+  desc "push", "Build and push app image to registry"
+  def push
+    cli = self
+
+    run_locally do
+      begin
+        MRSK.with_verbosity(:debug) { execute *MRSK.builder.push }
+      rescue SSHKit::Command::Failed => e
+        if e.message =~ /(no builder)|(no such file or directory)/
+          error "Missing compatible builder, so creating a new one first"
+
+          if cli.create
+            MRSK.with_verbosity(:debug) { execute *MRSK.builder.push }
+          end
+        else
+          raise
+        end
+      end
+    end
+  end
+
+  desc "pull", "Pull app image from registry onto servers"
+  def pull
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Pulled image with version #{MRSK.version}"), verbosity: :debug
+      execute *MRSK.builder.clean, raise_on_non_zero_exit: false
+      execute *MRSK.builder.pull
+    end
+  end
+
+  desc "create", "Create a build setup"
+  def create
+    run_locally do
+      begin
+        debug "Using builder: #{MRSK.builder.name}"
+        execute *MRSK.builder.create
+      rescue SSHKit::Command::Failed => e
+        if e.message =~ /stderr=(.*)/
+          error "Couldn't create remote builder: #{$1}"
+          false
+        else
+          raise
+        end
+      end
+    end
+  end
+
+  desc "remove", "Remove build setup"
+  def remove
+    run_locally do
+      debug "Using builder: #{MRSK.builder.name}"
+      execute *MRSK.builder.remove
+    end
+  end
+
+  desc "details", "Show build setup"
+  def details
+    run_locally do
+      puts "Builder: #{MRSK.builder.name}"
+      puts capture(*MRSK.builder.info)
+    end
+  end
+end

lib/mrsk/cli/healthcheck.rb

@@ -0,0 +1,48 @@
+class Mrsk::Cli::Healthcheck < Mrsk::Cli::Base
+  MAX_ATTEMPTS = 5
+
+  default_command :perform
+
+  desc "perform", "Health check current app version"
+  def perform
+    on(MRSK.primary_host) do
+      begin
+        execute *MRSK.healthcheck.run
+
+        target = "Health check against #{MRSK.config.healthcheck["path"]}"
+        attempt = 1
+
+        begin
+          status = capture_with_info(*MRSK.healthcheck.curl)
+
+          if status == "200"
+            info "#{target} succeeded with 200 OK!"
+          else
+            raise "#{target} failed with status #{status}"
+          end
+        rescue SSHKit::Command::Failed
+          if attempt <= MAX_ATTEMPTS
+            info "#{target} failed to respond, retrying in #{attempt}s..."
+            sleep attempt
+            attempt += 1
+
+            retry
+          else
+            raise
+          end
+        end
+      rescue SSHKit::Command::Failed => e
+        error capture_with_info(*MRSK.healthcheck.logs)
+
+        if e.message =~ /curl/
+          raise SSHKit::Command::Failed, "#{target} failed to return 200 OK!"
+        else
+          raise
+        end
+      ensure
+        execute *MRSK.healthcheck.stop, raise_on_non_zero_exit: false
+        execute *MRSK.healthcheck.remove, raise_on_non_zero_exit: false
+      end
+    end
+  end
+end

lib/mrsk/cli/main.rb

@@ -0,0 +1,187 @@
+class Mrsk::Cli::Main < Mrsk::Cli::Base
+  desc "setup", "Setup all accessories and deploy app to servers"
+  def setup
+    print_runtime do
+      invoke "mrsk:cli:server:bootstrap"
+      invoke "mrsk:cli:accessory:boot", [ "all" ]
+      deploy
+    end
+  end
+
+  desc "deploy", "Deploy app to servers"
+  def deploy
+    runtime = print_runtime do
+      say "Ensure Docker is installed...", :magenta
+      invoke "mrsk:cli:server:bootstrap"
+
+      say "Log into image registry...", :magenta
+      invoke "mrsk:cli:registry:login"
+
+      say "Build and push app image...", :magenta
+      invoke "mrsk:cli:build:deliver"
+
+      say "Ensure Traefik is running...", :magenta
+      invoke "mrsk:cli:traefik:boot"
+
+      say "Ensure app can pass healthcheck...", :magenta
+      invoke "mrsk:cli:healthcheck:perform"
+
+      invoke "mrsk:cli:app:boot"
+
+      say "Prune old containers and images...", :magenta
+      invoke "mrsk:cli:prune:all"
+    end
+
+    audit_broadcast "Deployed app in #{runtime.to_i} seconds"
+  end
+
+  desc "redeploy", "Deploy app to servers without bootstrapping servers, starting Traefik, pruning, and registry login"
+  def redeploy
+    runtime = print_runtime do
+      say "Build and push app image...", :magenta
+      invoke "mrsk:cli:build:deliver"
+
+      say "Ensure app can pass healthcheck...", :magenta
+      invoke "mrsk:cli:healthcheck:perform"
+
+      invoke "mrsk:cli:app:boot"
+    end
+
+    audit_broadcast "Redeployed app in #{runtime.to_i} seconds"
+  end
+
+  desc "rollback [VERSION]", "Rollback app to VERSION"
+  def rollback(version)
+    MRSK.version = version
+
+    if container_name_available?(MRSK.config.service_with_version)
+      say "Stop current version, then start version #{version}...", :magenta
+
+      on(MRSK.hosts) do |host|
+        execute *MRSK.app.stop, raise_on_non_zero_exit: false
+        execute *MRSK.app.start
+      end
+
+      audit_broadcast "Rolled back app to version #{version}"
+    else
+      say "The app version '#{version}' is not available as a container (use 'mrsk app containers' for available versions)", :red
+    end
+  end
+
+  desc "details", "Show details about all containers"
+  def details
+    invoke "mrsk:cli:traefik:details"
+    invoke "mrsk:cli:app:details"
+    invoke "mrsk:cli:accessory:details", [ "all" ]
+  end
+
+  desc "audit", "Show audit log from servers"
+  def audit
+    on(MRSK.hosts) do |host|
+      puts_by_host host, capture_with_info(*MRSK.auditor.reveal)
+    end
+  end
+
+  desc "config", "Show combined config (including secrets!)"
+  def config
+    run_locally do
+      puts MRSK.config.to_h.to_yaml
+    end
+  end
+
+  desc "init", "Create config stub in config/deploy.yml and env stub in .env"
+  option :bundle, type: :boolean, default: false, desc: "Add MRSK to the Gemfile and create a bin/mrsk binstub"
+  def init
+    require "fileutils"
+
+    if (deploy_file = Pathname.new(File.expand_path("config/deploy.yml"))).exist?
+      puts "Config file already exists in config/deploy.yml (remove first to create a new one)"
+    else
+      FileUtils.mkdir_p deploy_file.dirname
+      FileUtils.cp_r Pathname.new(File.expand_path("templates/deploy.yml", __dir__)), deploy_file
+      puts "Created configuration file in config/deploy.yml"
+    end
+
+    unless (deploy_file = Pathname.new(File.expand_path(".env"))).exist?
+      FileUtils.cp_r Pathname.new(File.expand_path("templates/template.env", __dir__)), deploy_file
+      puts "Created .env file"
+    end
+
+    if options[:bundle]
+      if (binstub = Pathname.new(File.expand_path("bin/mrsk"))).exist?
+        puts "Binstub already exists in bin/mrsk (remove first to create a new one)"
+      else
+        puts "Adding MRSK to Gemfile and bundle..."
+        `bundle add mrsk`
+        `bundle binstubs mrsk`
+        puts "Created binstub file in bin/mrsk"
+      end
+    end
+  end
+
+  desc "envify", "Create .env by evaluating .env.erb (or .env.staging.erb -> .env.staging when using -d staging)"
+  def envify
+    if destination = options[:destination]
+      env_template_path = ".env.#{destination}.erb"
+      env_path          = ".env.#{destination}"
+    else
+      env_template_path = ".env.erb"
+      env_path          = ".env"
+    end
+
+    File.write(env_path, ERB.new(File.read(env_template_path)).result, perm: 0600)
+  end
+
+  desc "remove", "Remove Traefik, app, accessories, and registry session from servers"
+  option :confirmed, aliases: "-y", type: :boolean, default: false, desc: "Proceed without confirmation question"
+  def remove
+    if options[:confirmed] || ask(remove_confirmation_question, limited_to: %w( y N ), default: "N") == "y"
+      invoke "mrsk:cli:traefik:remove", [], options.without(:confirmed)
+      invoke "mrsk:cli:app:remove", [], options.without(:confirmed)
+      invoke "mrsk:cli:accessory:remove", [ "all" ]
+      invoke "mrsk:cli:registry:logout", [], options.without(:confirmed)
+    end
+  end
+
+  desc "version", "Show MRSK version"
+  def version
+    puts Mrsk::VERSION
+  end
+
+  desc "accessory", "Manage accessories (db/redis/search)"
+  subcommand "accessory", Mrsk::Cli::Accessory
+
+  desc "app", "Manage application"
+  subcommand "app", Mrsk::Cli::App
+
+  desc "build", "Build application image"
+  subcommand "build", Mrsk::Cli::Build
+
+  desc "healthcheck", "Healthcheck application"
+  subcommand "healthcheck", Mrsk::Cli::Healthcheck
+
+  desc "prune", "Prune old application images and containers"
+  subcommand "prune", Mrsk::Cli::Prune
+
+  desc "registry", "Login and -out of the image registry"
+  subcommand "registry", Mrsk::Cli::Registry
+
+  desc "server", "Bootstrap servers with Docker"
+  subcommand "server", Mrsk::Cli::Server
+
+  desc "traefik", "Manage Traefik load balancer"
+  subcommand "traefik", Mrsk::Cli::Traefik
+
+  private
+    def container_name_available?(container_name, host: MRSK.primary_host)
+      container_names = nil
+      on(host) { container_names = capture_with_info(*MRSK.app.list_container_names).split("\n") }
+      Array(container_names).include?(container_name)
+    end
+
+    def remove_confirmation_question      
+      "This will remove all containers and images. " +
+      (MRSK.config.accessories.any? ? "Including #{MRSK.config.accessories.collect(&:name).to_sentence}. " : "") +
+      "Are you sure?"
+    end
+end

lib/mrsk/cli/prune.rb

@@ -0,0 +1,23 @@
+class Mrsk::Cli::Prune < Mrsk::Cli::Base
+  desc "all", "Prune unused images and stopped containers"
+  def all
+    containers
+    images
+  end
+
+  desc "images", "Prune unused images older than 7 days"
+  def images
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Pruned images"), verbosity: :debug
+      execute *MRSK.prune.images
+    end
+  end
+
+  desc "containers", "Prune stopped containers older than 3 days"
+  def containers
+    on(MRSK.hosts) do
+      execute *MRSK.auditor.record("Pruned containers"), verbosity: :debug
+      execute *MRSK.prune.containers
+    end
+  end
+end

lib/mrsk/cli/registry.rb

@@ -0,0 +1,18 @@
+class Mrsk::Cli::Registry < Mrsk::Cli::Base
+  desc "login", "Log in to registry locally and remotely"
+  def login
+    run_locally    { execute *MRSK.registry.login }
+    on(MRSK.hosts) { execute *MRSK.registry.login }
+  # FIXME: This rescue needed?
+  rescue ArgumentError => e
+    puts e.message
+  end
+
+  desc "logout", "Log out of registry remotely"
+  def logout
+    on(MRSK.hosts) { execute *MRSK.registry.logout }
+  # FIXME: This rescue needed?
+  rescue ArgumentError => e
+    puts e.message
+  end
+end

lib/mrsk/cli/server.rb

@@ -0,0 +1,6 @@
+class Mrsk::Cli::Server < Mrsk::Cli::Base
+  desc "bootstrap", "Ensure Docker is installed on servers"
+  def bootstrap
+    on(MRSK.hosts + MRSK.accessory_hosts) { execute "which docker || (apt-get update -y && apt-get install docker.io -y)" }
+  end
+end

lib/mrsk/cli/templates/deploy.yml

@@ -0,0 +1,76 @@
+# Name of your application. Used to uniquely configure containers.
+service: my-app
+
+# Name of the container image.
+image: user/my-app
+
+# Deploy to these servers.
+servers:
+  - 192.168.0.1
+
+# Credentials for your image host.
+registry:
+  # Specify the registry server, if you're not using Docker Hub
+  # server: registry.digitalocean.com / ghcr.io / ...
+  username: my-user
+  password:
+    - MRSK_REGISTRY_PASSWORD
+
+# Inject ENV variables into containers (secrets come from .env).
+# env:
+#   clear:
+#     DB_HOST: 192.168.0.2
+#   secret:
+#     - RAILS_MASTER_KEY
+
+# Call a broadcast command on deploys.
+# audit_broadcast_cmd:
+#   bin/broadcast_to_bc
+
+# Use a different ssh user than root
+# ssh:
+#   user: app
+
+# Configure builder setup.
+# builder:
+#   args:
+#     RUBY_VERSION: 3.2.0
+#   secrets:
+#     - GITHUB_TOKEN
+#   remote:
+#     arch: amd64
+#     host: ssh://app@192.168.0.1
+
+# Use accessory services (secrets come from .env).
+# accessories:
+#   db:
+#     image: mysql:8.0
+#     host: 192.168.0.2
+#     port: 3306
+#     env:
+#       clear:
+#         MYSQL_ROOT_HOST: '%'
+#       secret:
+#         - MYSQL_ROOT_PASSWORD
+#     files:
+#       - config/mysql/production.cnf:/etc/mysql/my.cnf
+#       - db/production.sql.erb:/docker-entrypoint-initdb.d/setup.sql
+#     directories:
+#       - data:/var/lib/mysql
+#   redis:
+#     image: redis:7.0
+#     host: 192.168.0.2
+#     port: 6379
+#     directories:
+#       - data:/data
+
+# Configure custom arguments for Traefik
+# traefik:
+#   args:
+#     accesslog: true
+#     accesslog.format: json
+
+# Configure a custom healthcheck (default is /up on port 3000)
+# healthcheck:
+#   path: /healthz
+#   port: 4000

lib/mrsk/cli/templates/template.env

@@ -0,0 +1,2 @@
+MRSK_REGISTRY_PASSWORD=change-this
+RAILS_MASTER_KEY=another-env

lib/mrsk/cli/traefik.rb

@@ -0,0 +1,87 @@
+class Mrsk::Cli::Traefik < Mrsk::Cli::Base
+  desc "boot", "Boot Traefik on servers"
+  def boot
+    on(MRSK.traefik_hosts) { execute *MRSK.traefik.run, raise_on_non_zero_exit: false }
+  end
+
+  desc "reboot", "Reboot Traefik on servers (stop container, remove container, start new container)"
+  def reboot
+    stop
+    remove_container
+    boot
+  end
+
+  desc "start", "Start existing Traefik container on servers"
+  def start
+    on(MRSK.traefik_hosts) do
+      execute *MRSK.auditor.record("Started traefik"), verbosity: :debug
+      execute *MRSK.traefik.start, raise_on_non_zero_exit: false
+    end
+  end
+
+  desc "stop", "Stop existing Traefik container on servers"
+  def stop
+    on(MRSK.traefik_hosts) do
+      execute *MRSK.auditor.record("Stopped traefik"), verbosity: :debug
+      execute *MRSK.traefik.stop, raise_on_non_zero_exit: false
+    end
+  end
+
+  desc "restart", "Restart existing Traefik container on servers"
+  def restart
+    stop
+    start
+  end
+
+  desc "details", "Show details about Traefik container from servers"
+  def details
+    on(MRSK.traefik_hosts) { |host| puts_by_host host, capture_with_info(*MRSK.traefik.info), type: "Traefik" }
+  end
+
+  desc "logs", "Show log lines from Traefik on servers"
+  option :since, aliases: "-s", desc: "Show logs since timestamp (e.g. 2013-01-02T13:23:37Z) or relative (e.g. 42m for 42 minutes)"
+  option :lines, type: :numeric, aliases: "-n", desc: "Number of log lines to pull from each server"
+  option :grep, aliases: "-g", desc: "Show lines with grep match only (use this to fetch specific requests by id)"
+  option :follow, aliases: "-f", desc: "Follow logs on primary server (or specific host set by --hosts)"
+  def logs
+    grep = options[:grep]
+
+    if options[:follow]
+      run_locally do
+        info "Following logs on #{MRSK.primary_host}..."
+        info MRSK.traefik.follow_logs(host: MRSK.primary_host, grep: grep)
+        exec MRSK.traefik.follow_logs(host: MRSK.primary_host, grep: grep)
+      end
+    else
+      since = options[:since]
+      lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
+
+      on(MRSK.traefik_hosts) do |host|
+        puts_by_host host, capture(*MRSK.traefik.logs(since: since, lines: lines, grep: grep)), type: "Traefik"
+      end
+    end
+  end
+
+  desc "remove", "Remove Traefik container and image from servers"
+  def remove
+    stop
+    remove_container
+    remove_image
+  end
+
+  desc "remove_container", "Remove Traefik container from servers", hide: true
+  def remove_container
+    on(MRSK.traefik_hosts) do
+      execute *MRSK.auditor.record("Removed traefik container"), verbosity: :debug
+      execute *MRSK.traefik.remove_container
+    end
+  end
+
+  desc "remove_container", "Remove Traefik image from servers", hide: true
+  def remove_image
+    on(MRSK.traefik_hosts) do
+      execute *MRSK.auditor.record("Removed traefik image"), verbosity: :debug
+      execute *MRSK.traefik.remove_image
+    end
+  end
+end

lib/mrsk/commander.rb

@@ -0,0 +1,119 @@
+require "active_support/core_ext/enumerable"
+
+class Mrsk::Commander
+  attr_accessor :config_file, :destination, :verbosity, :version
+
+  def initialize(config_file: nil, destination: nil, verbosity: :info)
+    @config_file, @destination, @verbosity = config_file, destination, verbosity
+  end
+
+  def config
+    @config ||= \
+      Mrsk::Configuration
+        .create_from(config_file, destination: destination, version: cascading_version)
+        .tap { |config| configure_sshkit_with(config) }
+  end
+
+  attr_accessor :specific_hosts
+
+  def specific_primary!
+    self.specific_hosts = [ config.primary_web_host ]
+  end
+
+  def specific_roles=(role_names)
+    self.specific_hosts = config.roles.select { |r| role_names.include?(r.name) }.flat_map(&:hosts) if role_names.present?
+  end
+
+  def primary_host
+    specific_hosts&.sole || config.primary_web_host
+  end
+
+  def hosts
+    specific_hosts || config.all_hosts
+  end
+
+  def traefik_hosts
+    specific_hosts || config.traefik_hosts
+  end
+
+  def accessory_hosts
+    specific_hosts || config.accessories.collect(&:host)
+  end
+
+  def accessory_names
+    config.accessories&.collect(&:name) || []
+  end
+
+
+  def app
+    @app ||= Mrsk::Commands::App.new(config)
+  end
+
+  def accessory(name)
+    Mrsk::Commands::Accessory.new(config, name: name)
+  end
+
+  def auditor
+    @auditor ||= Mrsk::Commands::Auditor.new(config)
+  end
+
+  def builder
+    @builder ||= Mrsk::Commands::Builder.new(config)
+  end
+
+  def healthcheck
+    @healthcheck ||= Mrsk::Commands::Healthcheck.new(config)
+  end
+
+  def prune
+    @prune ||= Mrsk::Commands::Prune.new(config)
+  end
+
+  def registry
+    @registry ||= Mrsk::Commands::Registry.new(config)
+  end
+
+  def traefik
+    @traefik ||= Mrsk::Commands::Traefik.new(config)
+  end
+
+
+  def with_verbosity(level)
+    old_level = self.verbosity
+
+    self.verbosity = level
+    SSHKit.config.output_verbosity = level
+
+    yield
+  ensure
+    self.verbosity = old_level
+    SSHKit.config.output_verbosity = old_level
+  end
+
+  # Test-induced damage!
+  def reset
+    @config = @config_file = @destination = @version = nil
+    @app = @builder = @traefik = @registry = @prune = @auditor = nil
+    @verbosity = :info
+  end
+
+  private
+    def cascading_version
+      version.presence || ENV["VERSION"] || current_commit_hash
+    end
+
+    def current_commit_hash
+      if system("git rev-parse")
+        `git rev-parse HEAD`.strip
+      else
+        raise "Can't use commit hash as version, no git repository found in #{Dir.pwd}"
+      end
+    end
+
+    # Lazy setup of SSHKit
+    def configure_sshkit_with(config)
+      SSHKit::Backend::Netssh.configure { |ssh| ssh.ssh_options = config.ssh_options }
+      SSHKit.config.command_map[:docker] = "docker" # No need to use /usr/bin/env, just clogs up the logs
+      SSHKit.config.output_verbosity = verbosity
+    end
+end

lib/mrsk/commands.rb

@@ -1,13 +1,2 @@
 module Mrsk::Commands
-  class Base
-    attr_accessor :config
-
-    def initialize(config)
-      @config = config
-    end
-  end
 end
-
-require "mrsk/commands/app"
-require "mrsk/commands/traefik"
-require "mrsk/commands/registry"

lib/mrsk/commands/accessory.rb

@@ -0,0 +1,110 @@
+class Mrsk::Commands::Accessory < Mrsk::Commands::Base
+  attr_reader :accessory_config
+  delegate :service_name, :image, :host, :port, :files, :directories, :env_args, :volume_args, :label_args, to: :accessory_config
+
+  def initialize(config, name:)
+    super(config)
+    @accessory_config = config.accessory(name)
+  end
+
+  def run
+    docker :run,
+      "--name", service_name,
+      "--detach",
+      "--restart", "unless-stopped",
+      "--log-opt", "max-size=#{MAX_LOG_SIZE}",
+      "--publish", port,
+      *env_args,
+      *volume_args,
+      *label_args,
+      image
+  end
+
+  def start
+    docker :container, :start, service_name
+  end
+
+  def stop
+    docker :container, :stop, service_name
+  end
+
+  def info
+    docker :ps, *service_filter
+  end
+
+
+  def logs(since: nil, lines: nil, grep: nil)
+    pipe \
+      docker(:logs, service_name, (" --since #{since}" if since), (" --tail #{lines}" if lines), "--timestamps", "2>&1"),
+      ("grep '#{grep}'" if grep)
+  end
+
+  def follow_logs(grep: nil)
+    run_over_ssh \
+      pipe \
+        docker(:logs, service_name, "--timestamps", "--tail", "10", "--follow", "2>&1"),
+        (%(grep "#{grep}") if grep)
+  end
+
+
+  def execute_in_existing_container(*command, interactive: false)
+    docker :exec,
+      ("-it" if interactive),
+      service_name,
+      *command
+  end
+
+  def execute_in_new_container(*command, interactive: false)
+    docker :run,
+      ("-it" if interactive),
+      "--rm",
+      *env_args,
+      *volume_args,
+      image,
+      *command
+  end
+
+  def execute_in_existing_container_over_ssh(*command)
+    run_over_ssh execute_in_existing_container(*command, interactive: true)
+  end
+
+  def execute_in_new_container_over_ssh(*command)
+    run_over_ssh execute_in_new_container(*command, interactive: true)
+  end
+
+  def run_over_ssh(command)
+    super command, host: host
+  end
+
+
+  def ensure_local_file_present(local_file)
+    if !local_file.is_a?(StringIO) && !Pathname.new(local_file).exist?
+      raise "Missing file: #{local_file}"
+    end
+  end
+
+  def make_directory_for(remote_file)
+    make_directory Pathname.new(remote_file).dirname.to_s
+  end
+
+  def make_directory(path)
+    [ :mkdir, "-p", path ]
+  end
+
+  def remove_service_directory
+    [ :rm, "-rf", service_name ]
+  end
+
+  def remove_container
+    docker :container, :prune, "--force", *service_filter
+  end
+
+  def remove_image
+    docker :image, :prune, "--all", "--force", *service_filter
+  end
+
+  private
+    def service_filter
+      [ "--filter", "label=service=#{service_name}" ]
+    end
+end

lib/mrsk/commands/app.rb

@@ -1,22 +1,138 @@
 class Mrsk::Commands::App < Mrsk::Commands::Base
-  def push
-    # TODO: Run 'docker buildx create --use' when needed
-    "docker buildx build --push --platform=linux/amd64,linux/arm64 -t #{config.absolute_image} ."
-  end
+  def run(role: :web)
+    role = config.role(role)
 
-  def pull
-    "docker pull #{config.absolute_image}"
+    docker :run,
+      "--detach",
+      "--restart unless-stopped",
+      "--log-opt", "max-size=#{MAX_LOG_SIZE}",
+      "--name", service_with_version,
+      *role.env_args,
+      *config.volume_args,
+      *role.label_args,
+      config.absolute_image,
+      role.cmd
   end
 
   def start
-    "docker run -d --rm --name #{config.service_with_version} #{config.envs} #{config.labels} #{config.absolute_image}"
+    docker :start, service_with_version
   end
 
   def stop
-    "docker ps -q --filter label=service=#{config.service} | xargs docker stop"
+    pipe current_container_id, xargs(docker(:stop))
   end
 
   def info
-    "docker ps --filter label=service=#{config.service}"
+    docker :ps, *service_filter
   end
+
+
+  def logs(since: nil, lines: nil, grep: nil)
+    pipe \
+      current_container_id,
+      "xargs docker logs#{" --since #{since}" if since}#{" --tail #{lines}" if lines} 2>&1",
+      ("grep '#{grep}'" if grep)
+  end
+
+  def follow_logs(host:, grep: nil)
+    run_over_ssh \
+      pipe(
+        current_container_id,
+        "xargs docker logs --timestamps --tail 10 --follow 2>&1",
+        (%(grep "#{grep}") if grep)
+      ),
+      host: host
+  end
+
+
+  def execute_in_existing_container(*command, interactive: false)
+    docker :exec,
+      ("-it" if interactive),
+      config.service_with_version,
+      *command
+  end
+
+  def execute_in_new_container(*command, interactive: false)
+    docker :run,
+      ("-it" if interactive),
+      "--rm",
+      *config.env_args,
+      *config.volume_args,
+      config.absolute_image,
+      *command
+  end
+
+  def execute_in_existing_container_over_ssh(*command, host:)
+    run_over_ssh execute_in_existing_container(*command, interactive: true), host: host
+  end
+
+  def execute_in_new_container_over_ssh(*command, host:)
+    run_over_ssh execute_in_new_container(*command, interactive: true), host: host
+  end
+
+
+  def current_container_id
+    docker :ps, "--quiet", *service_filter
+  end
+
+  def current_running_version
+    # FIXME: Find more graceful way to extract the version from "app-version" than using sed and tail!
+    pipe \
+      docker(:ps, "--filter", "label=service=#{config.service}", "--format", '"{{.Names}}"'),
+      %(sed 's/-/\\n/g'),
+      "tail -n 1"
+  end
+
+  def most_recent_version_from_available_images
+    pipe \
+      docker(:image, :ls, "--format", '"{{.Tag}}"', config.repository),
+      "head -n 1"
+  end
+
+  def all_versions_from_available_containers
+    pipe \
+      docker(:image, :ls, "--format", '"{{.Tag}}"', config.repository),
+      "head -n 1"
+  end
+
+
+  def list_containers
+    docker :container, :ls, "--all", *service_filter
+  end
+
+  def list_container_names
+    [ *list_containers, "--format", "'{{ .Names }}'" ]
+  end
+
+  def remove_container(version:)
+    pipe \
+      container_id_for(container_name: service_with_version(version)),
+      xargs(docker(:container, :rm))
+  end
+
+  def remove_containers
+    docker :container, :prune, "--force", *service_filter
+  end
+
+  def list_images
+    docker :image, :ls, config.repository
+  end
+
+  def remove_images
+    docker :image, :prune, "--all", "--force", *service_filter
+  end
+
+
+  private
+    def service_with_version(version = nil)
+      if version
+        "#{config.service}-#{version}"
+      else
+        config.service_with_version
+      end
+    end
+
+    def service_filter
+      [ "--filter", "label=service=#{config.service}" ]
+    end
 end

lib/mrsk/commands/auditor.rb

@@ -0,0 +1,42 @@
+require "active_support/core_ext/time/conversions"
+
+class Mrsk::Commands::Auditor < Mrsk::Commands::Base
+  # Runs remotely
+  def record(line)
+    append \
+      [ :echo, tagged_record_line(line) ],
+      audit_log_file
+  end
+
+  # Runs locally
+  def broadcast(line)
+    if broadcast_cmd = config.audit_broadcast_cmd
+      [ broadcast_cmd, tagged_broadcast_line(line) ]
+    end
+  end
+
+  def reveal
+    [ :tail, "-n", 50, audit_log_file ]
+  end
+
+  private
+    def audit_log_file
+      "mrsk-#{config.service}-audit.log"
+    end
+
+    def tagged_record_line(line)
+      "'#{recorded_at_tag} #{performer_tag} #{line}'"
+    end
+
+    def tagged_broadcast_line(line)
+      "'#{performer_tag} #{line}'"
+    end
+
+    def performer_tag
+      "[#{`whoami`.strip}]"
+    end
+
+    def recorded_at_tag
+      "[#{Time.now.to_fs(:db)}]"
+    end
+end

lib/mrsk/commands/base.rb

@@ -0,0 +1,52 @@
+module Mrsk::Commands
+  class Base
+    delegate :redact, to: Mrsk::Utils
+
+    MAX_LOG_SIZE = "10m"
+
+    attr_accessor :config
+
+    def initialize(config)
+      @config = config
+    end
+
+    def run_over_ssh(*command, host:)
+      "ssh".tap do |cmd|
+        cmd << " -J #{config.ssh_proxy.jump_proxies}" if config.ssh_proxy
+        cmd << " -t #{config.ssh_user}@#{host} '#{command.join(" ")}'"
+      end
+    end
+
+    def container_id_for(container_name:)
+      docker :container, :ls, "--all", "--filter", "name=#{container_name}", "--quiet"
+    end
+
+    private
+      def combine(*commands, by: "&&")
+        commands
+          .compact
+          .collect { |command| Array(command) + [ by ] }.flatten # Join commands
+          .tap     { |commands| commands.pop } # Remove trailing combiner
+      end
+
+      def chain(*commands)
+        combine *commands, by: ";"
+      end
+
+      def pipe(*commands)
+        combine *commands, by: "|"
+      end
+
+      def append(*commands)
+        combine *commands, by: ">>"
+      end
+
+      def xargs(command)
+        [ :xargs, command ].flatten
+      end
+
+      def docker(*args)
+        args.compact.unshift :docker
+      end
+  end
+end

lib/mrsk/commands/builder.rb

@@ -0,0 +1,36 @@
+class Mrsk::Commands::Builder < Mrsk::Commands::Base
+  delegate :create, :remove, :push, :clean, :pull, :info, to: :target
+
+  def name
+    target.class.to_s.remove("Mrsk::Commands::Builder::").underscore
+  end
+
+  def target
+    case
+    when config.builder && config.builder["multiarch"] == false
+      native
+    when config.builder && config.builder["local"] && config.builder["remote"]
+      multiarch_remote
+    when config.builder && config.builder["remote"]
+      native_remote
+    else
+      multiarch
+    end
+  end
+
+  def native
+    @native ||= Mrsk::Commands::Builder::Native.new(config)
+  end
+
+  def native_remote
+    @native ||= Mrsk::Commands::Builder::Native::Remote.new(config)
+  end
+
+  def multiarch
+    @multiarch ||= Mrsk::Commands::Builder::Multiarch.new(config)
+  end
+
+  def multiarch_remote
+    @multiarch_remote ||= Mrsk::Commands::Builder::Multiarch::Remote.new(config)
+  end
+end

lib/mrsk/commands/builder/base.rb

@@ -0,0 +1,40 @@
+class Mrsk::Commands::Builder::Base < Mrsk::Commands::Base
+  delegate :argumentize, to: Mrsk::Utils
+
+  def clean
+    docker :image, :rm, "--force", config.absolute_image
+  end
+
+  def pull
+    docker :pull, config.absolute_image
+  end
+
+  def build_options
+    [ *build_tags, *build_labels, *build_args, *build_secrets ]
+  end
+
+  private
+    def build_tags
+      [ "-t", config.absolute_image, "-t", config.latest_image ]
+    end
+
+    def build_labels
+      argumentize "--label", { service: config.service }
+    end
+
+    def build_args
+      argumentize "--build-arg", args, redacted: true
+    end
+
+    def build_secrets
+      argumentize "--secret", secrets.collect { |secret| [ "id", secret ] }
+    end
+
+    def args
+      (config.builder && config.builder["args"]) || {}
+    end
+
+    def secrets
+      (config.builder && config.builder["secrets"]) || []
+    end
+end

lib/mrsk/commands/builder/multiarch.rb

@@ -0,0 +1,29 @@
+class Mrsk::Commands::Builder::Multiarch < Mrsk::Commands::Builder::Base
+  def create
+    docker :buildx, :create, "--use", "--name", builder_name
+  end
+
+  def remove
+    docker :buildx, :rm, builder_name
+  end
+
+  def push
+    docker :buildx, :build,
+      "--push",
+      "--platform", "linux/amd64,linux/arm64",
+      "--builder", builder_name,
+      *build_options,
+      "."
+  end
+
+  def info
+    combine \
+      docker(:context, :ls),
+      docker(:buildx, :ls)
+  end
+
+  private
+    def builder_name
+      "mrsk-#{config.service}-multiarch"
+    end
+end

lib/mrsk/commands/builder/multiarch/remote.rb

@@ -0,0 +1,59 @@
+class Mrsk::Commands::Builder::Multiarch::Remote < Mrsk::Commands::Builder::Multiarch
+  def create
+    combine \
+      create_contexts,
+      create_local_buildx,
+      append_remote_buildx
+  end
+
+  def remove
+    combine \
+      remove_contexts,
+      super
+  end
+
+  private
+    def builder_name
+      super + "-remote"
+    end
+
+    def builder_name_with_arch(arch)
+      "#{builder_name}-#{arch}"
+    end
+
+    def create_local_buildx
+      docker :buildx, :create, "--name", builder_name, builder_name_with_arch(local["arch"]), "--platform", "linux/#{local["arch"]}"
+    end
+
+    def append_remote_buildx
+      docker :buildx, :create, "--append", "--name", builder_name, builder_name_with_arch(remote["arch"]), "--platform", "linux/#{remote["arch"]}"
+    end
+
+    def create_contexts
+      combine \
+        create_context(local["arch"], local["host"]),
+        create_context(remote["arch"], remote["host"])
+    end
+
+    def create_context(arch, host)
+      docker :context, :create, builder_name_with_arch(arch), "--description", "'#{builder_name} #{arch} native host'", "--docker", "'host=#{host}'"
+    end
+
+    def remove_contexts
+      combine \
+        remove_context(local["arch"]),
+        remove_context(remote["arch"])
+    end
+
+    def remove_context(arch)
+      docker :context, :rm, builder_name_with_arch(arch)
+    end
+
+    def local
+      config.builder["local"]
+    end
+
+    def remote
+      config.builder["remote"]
+    end
+end

lib/mrsk/commands/builder/native.rb

@@ -0,0 +1,19 @@
+class Mrsk::Commands::Builder::Native < Mrsk::Commands::Builder::Base
+  def create
+    # No-op on native
+  end
+
+  def remove
+    # No-op on native
+  end
+
+  def push
+    combine \
+      docker(:build, *build_options, "."),
+      docker(:push, config.absolute_image)
+  end
+
+  def info
+    # No-op on native
+  end
+end

lib/mrsk/commands/builder/native/remote.rb

@@ -0,0 +1,67 @@
+class Mrsk::Commands::Builder::Native::Remote < Mrsk::Commands::Builder::Native
+  def create
+    chain \
+      create_context,
+      create_buildx
+  end
+
+  def remove
+    chain \
+      remove_context,
+      remove_buildx
+  end
+
+  def push
+    docker :buildx, :build,
+      "--push",
+      "--platform", platform,
+      "--builder", builder_name,
+      *build_options,
+      "."
+  end
+
+  def info
+    chain \
+      docker(:context, :ls),
+      docker(:buildx, :ls)
+  end
+
+
+  private
+    def arch
+      config.builder["remote"]["arch"]
+    end
+
+    def host
+      config.builder["remote"]["host"]
+    end
+
+    def builder_name
+      "mrsk-#{config.service}-native-remote"
+    end
+
+    def builder_name_with_arch
+      "#{builder_name}-#{arch}"
+    end
+
+    def platform
+      "linux/#{arch}"
+    end
+
+    def create_context
+      docker :context, :create,
+        builder_name_with_arch, "--description", "'#{builder_name} #{arch} native host'", "--docker", "'host=#{host}'"
+    end
+
+    def remove_context
+      docker :context, :rm, builder_name_with_arch
+    end
+
+    def create_buildx
+      docker :buildx, :create, "--name", builder_name, builder_name_with_arch, "--platform", platform
+    end
+
+    def remove_buildx
+      docker :buildx, :rm, builder_name
+    end
+end

lib/mrsk/commands/healthcheck.rb

@@ -0,0 +1,50 @@
+class Mrsk::Commands::Healthcheck < Mrsk::Commands::Base
+  EXPOSED_PORT = 3999
+
+  def run
+    web = config.role(:web)
+
+    docker :run,
+      "--detach",
+      "--name", container_name_with_version,
+      "--publish", "#{EXPOSED_PORT}:#{config.healthcheck["port"]}",
+      "--label", "service=#{container_name}",
+      *web.env_args,
+      *config.volume_args,
+      config.absolute_image,
+      web.cmd
+  end
+
+  def curl
+    [ :curl, "--silent", "--output", "/dev/null", "--write-out", "'%{http_code}'", "--max-time", "2", health_url ]
+  end
+
+  def logs
+    pipe container_id, xargs(docker(:logs, "--tail", 50, "2>&1"))
+  end
+
+  def stop
+    pipe container_id, xargs(docker(:stop))
+  end
+
+  def remove
+    pipe container_id, xargs(docker(:container, :rm))
+  end
+
+  private
+    def container_name
+      "healthcheck-#{config.service}"
+    end
+
+    def container_name_with_version
+      "healthcheck-#{config.service_with_version}"
+    end
+
+    def container_id
+      container_id_for(container_name: container_name)
+    end
+
+    def health_url
+      "http://localhost:#{EXPOSED_PORT}#{config.healthcheck["path"]}"
+    end
+end

lib/mrsk/commands/prune.rb

@@ -0,0 +1,12 @@
+require "active_support/duration"
+require "active_support/core_ext/numeric/time"
+
+class Mrsk::Commands::Prune < Mrsk::Commands::Base
+  def images(until_hours: 7.days.in_hours.to_i)
+    docker :image, :prune, "--all", "--force", "--filter", "label=service=#{config.service}", "--filter", "until=#{until_hours}h"
+  end
+
+  def containers(until_hours: 3.days.in_hours.to_i)
+    docker :container, :prune, "--force", "--filter", "label=service=#{config.service}", "--filter", "until=#{until_hours}h"
+  end
+end

lib/mrsk/commands/registry.rb

@@ -1,5 +1,20 @@
 class Mrsk::Commands::Registry < Mrsk::Commands::Base
+  delegate :registry, to: :config
+
   def login
-    "docker login #{config.registry["server"]} -u #{config.registry["username"]} -p #{config.registry["password"]}"
+    docker :login, registry["server"], "-u", redact(registry["username"]), "-p", redact(lookup_password)
   end
+
+  def logout
+    docker :logout, registry["server"]
+  end
+
+  private
+    def lookup_password
+      if registry["password"].is_a?(Array)
+        ENV.fetch(registry["password"].first).dup
+      else
+        registry["password"]
+      end
+    end
 end

lib/mrsk/commands/traefik.rb

@@ -1,17 +1,52 @@
 class Mrsk::Commands::Traefik < Mrsk::Commands::Base
+  def run
+    docker :run, "--name traefik",
+      "--detach",
+      "--restart", "unless-stopped",
+      "--log-opt", "max-size=#{MAX_LOG_SIZE}",
+      "--publish", "80:80",
+      "--volume", "/var/run/docker.sock:/var/run/docker.sock",
+      "traefik",
+      "--providers.docker",
+      "--log.level=DEBUG",
+      *cmd_args
+  end
+
   def start
-    "docker run --name traefik " + 
-      "--rm -d " +
-      "-p 80:80 " +
-      "-v /var/run/docker.sock:/var/run/docker.sock " +
-      "traefik --providers.docker"
+    docker :container, :start, "traefik"
   end
 
   def stop
-    "docker container stop traefik"
+    docker :container, :stop, "traefik"
   end
 
   def info
-    "docker ps --filter name=traefik"
+    docker :ps, "--filter", "name=traefik"
   end
+
+  def logs(since: nil, lines: nil, grep: nil)
+    pipe \
+      docker(:logs, "traefik", (" --since #{since}" if since), (" --tail #{lines}" if lines), "--timestamps", "2>&1"),
+      ("grep '#{grep}'" if grep)
+  end
+
+  def follow_logs(host:, grep: nil)
+    run_over_ssh pipe(
+      docker(:logs, "traefik", "--timestamps", "--tail", "10", "--follow", "2>&1"),
+      (%(grep "#{grep}") if grep)
+    ).join(" "), host: host
+  end
+
+  def remove_container
+    docker :container, :prune, "--force", "--filter", "label=org.opencontainers.image.title=Traefik"
+  end
+
+  def remove_image
+    docker :image, :prune, "--all", "--force", "--filter", "label=org.opencontainers.image.title=Traefik"
+  end
+
+  private
+    def cmd_args
+      (config.raw_config.dig(:traefik, "args") || { }).collect { |(key, value)| [ "--#{key}", value ] }.flatten
+    end
 end

lib/mrsk/configuration.rb

@@ -1,78 +1,193 @@
 require "active_support/ordered_options"
+require "active_support/core_ext/string/inquiry"
+require "active_support/core_ext/module/delegation"
+require "pathname"
+require "erb"
+require "net/ssh/proxy/jump"
 
 class Mrsk::Configuration
-  delegate :service, :image, :env, :registry, :ssh_user, to: :config, allow_nil: true
+  delegate :service, :image, :servers, :env, :labels, :registry, :builder, to: :raw_config, allow_nil: true
+  delegate :argumentize, :argumentize_env_with_secrets, to: Mrsk::Utils
 
-  def self.load_file(file)
-    if file.exist?
-      new YAML.load_file(file).symbolize_keys
-    else
-      raise "Configuration file not found in #{file}"
+  attr_accessor :version
+  attr_accessor :raw_config
+
+  class << self
+    def create_from(base_config_file, destination: nil, version: "missing")
+      new(load_config_file(base_config_file).tap do |config|
+        if destination
+          config.deep_merge! \
+            load_config_file destination_config_file(base_config_file, destination)
+        end
+      end, version: version)
     end
+
+    private
+      def load_config_file(file)
+        if file.exist?
+          YAML.load(ERB.new(IO.read(file)).result).symbolize_keys
+        else
+          raise "Configuration file not found in #{file}"
+        end
+      end
+
+      def destination_config_file(base_config_file, destination)
+        dir, basename = base_config_file.split
+        dir.join basename.to_s.remove(".yml") + ".#{destination}.yml"
+      end
   end
 
-  def initialize(config)
-    @config = ActiveSupport::InheritableOptions.new(config)
-    ensure_required_keys_present
+  def initialize(raw_config, version: "missing", validate: true)
+    @raw_config = ActiveSupport::InheritableOptions.new(raw_config)
+    @version = version
+    valid? if validate
   end
 
-  def servers
-    ENV["SERVERS"] || config.servers
+
+  def roles
+    @roles ||= role_names.collect { |role_name| Role.new(role_name, config: self) }
   end
 
-  def version
-    @version ||= ENV["VERSION"] || `git rev-parse HEAD`.strip
+  def role(name)
+    roles.detect { |r| r.name == name.to_s }
+  end
+
+  def accessories
+    @accessories ||= raw_config.accessories&.keys&.collect { |name| Mrsk::Configuration::Accessory.new(name, config: self) } || []
+  end
+
+  def accessory(name)
+    accessories.detect { |a| a.name == name.to_s }
+  end
+
+
+  def all_hosts
+    roles.flat_map(&:hosts)
+  end
+
+  def primary_web_host
+    role(:web).hosts.first
+  end
+
+  def traefik_hosts
+    roles.select(&:running_traefik?).flat_map(&:hosts)
+  end
+
+
+  def repository
+    [ raw_config.registry["server"], image ].compact.join("/")
   end
 
   def absolute_image
-    [ config.registry["server"], image_with_version ].compact.join("/")
+    "#{repository}:#{version}"
   end
 
-  def image_with_version
-    "#{image}:#{version}"
+  def latest_image
+    "#{repository}:latest"
   end
 
   def service_with_version
     "#{service}-#{version}"
   end
 
-  def envs
-    parameterize "-e", \
-      { "RAILS_MASTER_KEY" => master_key }.merge(env || {})
+
+  def env_args
+    if raw_config.env.present?
+      argumentize_env_with_secrets(raw_config.env)
+    else
+      []
+    end
   end
 
-  def labels
-    parameterize "--label", \
-      "service" => service,
-      "traefik.http.routers.#{service}.rule" => "'PathPrefix(`/`)'",
-      "traefik.http.services.#{service}.loadbalancer.healthcheck.path" => "/up",
-      "traefik.http.services.#{service}.loadbalancer.healthcheck.interval" => "1s",
-      "traefik.http.middlewares.#{service}.retry.attempts" => "3",
-      "traefik.http.middlewares.#{service}.retry.initialinterval" => "500ms"
+  def volume_args
+    if raw_config.volumes.present?
+      argumentize "--volume", raw_config.volumes
+    else
+      []
+    end
+  end
+
+
+  def ssh_user
+    if raw_config.ssh.present?
+      raw_config.ssh["user"] || "root"
+    else
+      "root"
+    end
+  end
+
+  def ssh_proxy
+    if raw_config.ssh.present? && raw_config.ssh["proxy"]
+      Net::SSH::Proxy::Jump.new \
+        raw_config.ssh["proxy"].include?("@") ? raw_config.ssh["proxy"] : "root@#{raw_config.ssh["proxy"]}"
+    end
   end
 
   def ssh_options
-    { user: config.ssh_user || "root", auth_methods: [ "publickey" ] }
+    { user: ssh_user, proxy: ssh_proxy, auth_methods: [ "publickey" ] }.compact
   end
 
-  private
-    attr_accessor :config
 
+  def audit_broadcast_cmd
+    raw_config.audit_broadcast_cmd
+  end
+
+  def healthcheck
+    { "path" => "/up", "port" => 3000 }.merge(raw_config.healthcheck || {})
+  end
+
+
+  def valid?
+    ensure_required_keys_present && ensure_env_available
+  end
+
+
+  def to_h
+    {
+      roles: role_names,
+      hosts: all_hosts,
+      primary_host: primary_web_host,
+      version: version,
+      repository: repository,
+      absolute_image: absolute_image,
+      service_with_version: service_with_version,
+      env_args: env_args,
+      volume_args: volume_args,
+      ssh_options: ssh_options,
+      builder: raw_config.builder,
+      accessories: raw_config.accessories,
+      healthcheck: healthcheck
+    }.compact
+  end
+
+
+  private
+    # Will raise ArgumentError if any required config keys are missing
     def ensure_required_keys_present
-      %i[ service image registry ].each do |key|
-        raise ArgumentError, "Missing required configuration for #{key}" unless config[key].present?
+      %i[ service image registry servers ].each do |key|
+        raise ArgumentError, "Missing required configuration for #{key}" unless raw_config[key].present?
       end
 
-      %w[ username password ].each do |key|
-        raise ArgumentError, "Missing required configuration for registry/#{key}" unless config.registry[key].present?
-      end      
+      if raw_config.registry["username"].blank?
+        raise ArgumentError, "You must specify a username for the registry in config/deploy.yml"
+      end
+
+      if raw_config.registry["password"].blank?
+        raise ArgumentError, "You must specify a password for the registry in config/deploy.yml (or set the ENV variable if that's used)"
+      end
+
+      true
     end
 
-    def parameterize(param, hash)
-      hash.collect { |k, v| "#{param} #{k}=#{v}" }.join(" ")
+    # Will raise KeyError if any secret ENVs are missing
+    def ensure_env_available
+      env_args
+      roles.each(&:env_args)
+
+      true
     end
 
-    def master_key
-      ENV["RAILS_MASTER_KEY"] || File.read(Rails.root.join("config/master.key"))
+    def role_names
+      raw_config.servers.is_a?(Array) ? [ "web" ] : raw_config.servers.keys.sort
     end
 end

lib/mrsk/configuration/accessory.rb

@@ -0,0 +1,123 @@
+class Mrsk::Configuration::Accessory
+  delegate :argumentize, :argumentize_env_with_secrets, to: Mrsk::Utils
+
+  attr_accessor :name, :specifics
+
+  def initialize(name, config:)
+    @name, @config, @specifics = name.inquiry, config, config.raw_config["accessories"][name]
+  end
+
+  def service_name
+    "#{config.service}-#{name}"
+  end
+
+  def image
+    specifics["image"]
+  end
+
+  def host
+    specifics["host"] || raise(ArgumentError, "Missing host for accessory")
+  end
+
+  def port
+    if specifics["port"].to_s.include?(":")
+      specifics["port"]
+    else
+      "#{specifics["port"]}:#{specifics["port"]}"
+    end
+  end
+
+  def labels
+    default_labels.merge(specifics["labels"] || {})
+  end
+
+  def label_args
+    argumentize "--label", labels
+  end
+
+  def env
+    specifics["env"] || {}
+  end
+
+  def env_args
+    argumentize_env_with_secrets env
+  end
+
+  def files
+    specifics["files"]&.to_h do |local_to_remote_mapping|
+      local_file, remote_file = local_to_remote_mapping.split(":")
+      [ expand_local_file(local_file), expand_remote_file(remote_file) ]
+    end || {}
+  end
+
+  def directories
+    specifics["directories"]&.to_h do |host_to_container_mapping|
+      host_relative_path, container_path = host_to_container_mapping.split(":")
+      [ expand_host_path(host_relative_path), container_path ]
+    end || {}
+  end
+
+  def volumes
+    specific_volumes + remote_files_as_volumes + remote_directories_as_volumes
+  end
+
+  def volume_args
+    argumentize "--volume", volumes
+  end
+
+  private
+    attr_accessor :config
+
+    def default_labels
+      { "service" => service_name }
+    end
+
+    def expand_local_file(local_file)
+      if local_file.end_with?("erb")
+        with_clear_env_loaded { read_dynamic_file(local_file) }
+      else
+        Pathname.new(File.expand_path(local_file)).to_s
+      end
+    end
+
+    def with_clear_env_loaded
+      (env["clear"] || env).each { |k, v| ENV[k] = v }
+      yield
+    ensure
+      (env["clear"] || env).each { |k, v| ENV.delete(k) }
+    end
+
+    def read_dynamic_file(local_file)
+      StringIO.new(ERB.new(IO.read(local_file)).result)
+    end
+
+    def expand_remote_file(remote_file)
+      service_name + remote_file
+    end
+
+    def specific_volumes
+      specifics["volumes"] || []
+    end
+
+    def remote_files_as_volumes
+      specifics["files"]&.collect do |local_to_remote_mapping|
+        _, remote_file = local_to_remote_mapping.split(":")
+        "#{service_data_directory + remote_file}:#{remote_file}"
+      end || []
+    end
+
+    def remote_directories_as_volumes
+      specifics["directories"]&.collect do |host_to_container_mapping|
+        host_relative_path, container_path = host_to_container_mapping.split(":")
+        [ expand_host_path(host_relative_path), container_path ].join(":")
+      end || []
+    end
+
+    def expand_host_path(host_relative_path)
+      "#{service_data_directory}/#{host_relative_path}"
+    end
+
+    def service_data_directory
+      "$PWD/#{service_name}"
+    end
+end

lib/mrsk/configuration/role.rb

@@ -0,0 +1,107 @@
+class Mrsk::Configuration::Role
+  delegate :argumentize, :argumentize_env_with_secrets, to: Mrsk::Utils
+
+  attr_accessor :name
+
+  def initialize(name, config:)
+   @name, @config = name.inquiry, config
+  end
+
+  def hosts
+    @hosts ||= extract_hosts_from_config
+  end
+
+  def labels
+    default_labels.merge(traefik_labels).merge(custom_labels)
+  end
+
+  def label_args
+    argumentize "--label", labels
+  end
+
+  def env
+    if config.env && config.env["secret"]
+      merged_env_with_secrets
+    else
+      merged_env
+    end
+  end
+
+  def env_args
+    argumentize_env_with_secrets env
+  end
+
+  def cmd
+    specializations["cmd"]
+  end
+
+  def running_traefik?
+    name.web? || specializations["traefik"]
+  end
+
+  private
+    attr_accessor :config
+
+    def extract_hosts_from_config
+      if config.servers.is_a?(Array)
+        config.servers
+      else
+        servers = config.servers[name]
+        servers.is_a?(Array) ? servers : servers["hosts"]
+      end
+    end
+
+    def default_labels
+      { "service" => config.service, "role" => name }
+    end
+
+    def traefik_labels
+      if running_traefik?
+        {
+          "traefik.http.routers.#{config.service}.rule" => "PathPrefix(`/`)",
+          "traefik.http.services.#{config.service}.loadbalancer.healthcheck.path" => config.healthcheck["path"],
+          "traefik.http.services.#{config.service}.loadbalancer.healthcheck.interval" => "1s",
+          "traefik.http.middlewares.#{config.service}.retry.attempts" => "3",
+          "traefik.http.middlewares.#{config.service}.retry.initialinterval" => "500ms"
+        }
+      else
+        {}
+      end
+    end
+
+    def custom_labels
+      Hash.new.tap do |labels|
+        labels.merge!(config.labels) if config.labels.present?
+        labels.merge!(specializations["labels"]) if specializations["labels"].present?
+      end
+    end
+
+    def specializations
+      if config.servers.is_a?(Array) || config.servers[name].is_a?(Array)
+        { }
+      else
+        config.servers[name].except("hosts")
+      end
+    end
+
+    def specialized_env
+      specializations["env"] || {}
+    end
+
+    def merged_env
+      config.env&.merge(specialized_env) || {}
+    end
+
+    # Secrets are stored in an array, which won't merge by default, so have to do it by hand.
+    def merged_env_with_secrets
+      merged_env.tap do |new_env|
+        new_env["secret"] = Array(config.env["secret"]) + Array(specialized_env["secret"])
+
+        # If there's no secret/clear split, everything is clear
+        clear_app_env  = config.env["secret"] ? Array(config.env["clear"]) : Array(config.env["clear"] || config.env)
+        clear_role_env = specialized_env["secret"] ? Array(specialized_env["clear"]) : Array(specialized_env["clear"] || specialized_env)
+
+        new_env["clear"] = (clear_app_env + clear_role_env).uniq
+      end
+    end
+end

lib/mrsk/engine.rb

@@ -1,4 +0,0 @@
-module Mrsk
-  class Engine < ::Rails::Engine
-  end
-end

lib/mrsk/sshkit_with_ext.rb

@@ -0,0 +1,12 @@
+require "sshkit"
+require "sshkit/dsl"
+
+class SSHKit::Backend::Abstract
+  def capture_with_info(*args)
+    capture(*args, verbosity: Logger::INFO)
+  end
+
+  def puts_by_host(host, output, type: "App")
+    puts "#{type} Host: #{host}\n#{output}\n\n"
+  end
+end

lib/mrsk/utils.rb

@@ -0,0 +1,30 @@
+module Mrsk::Utils
+  extend self
+
+  # Return a list of escaped shell arguments using the same named argument against the passed attributes (hash or array).
+  def argumentize(argument, attributes, redacted: false)
+    Array(attributes).flat_map do |key, value|
+      if value.present?
+        escaped_pair = [ key, value.to_s.dump.gsub(/`/, '\\\\`') ].join("=")
+        [ argument, redacted ? redact(escaped_pair) : escaped_pair ]
+      else
+        [ argument, key ]
+      end
+    end
+  end
+
+  # Return a list of shell arguments using the same named argument against the passed attributes,
+  # but redacts and expands secrets.
+  def argumentize_env_with_secrets(env)
+    if (secrets = env["secret"]).present?
+      argumentize("-e", secrets.to_h { |key| [ key, ENV.fetch(key) ] }, redacted: true) + argumentize("-e", env["clear"])
+    else
+      argumentize "-e", env.fetch("clear", env)
+    end
+  end
+
+  # Copied from SSHKit::Backend::Abstract#redact to be available inside Commands classes
+  def redact(arg) # Used in execute_command to hide redact() args a user passes in
+    arg.to_s.extend(SSHKit::Redaction) # to_s due to our inability to extend Integer, etc
+  end
+end

lib/mrsk/version.rb

@@ -1,3 +1,3 @@
 module Mrsk
-  VERSION = "0.0.1"
+  VERSION = "0.8.1"
 end

lib/tasks/mrsk/app.rake

@@ -1,31 +0,0 @@
-require_relative "setup"
-
-app = Mrsk::Commands::App.new(MRSK_CONFIG)
-
-namespace :mrsk do
-  namespace :app do
-    desc "Build and push app image to servers"
-    task :push do
-      run_locally             { execute app.push }
-      on(MRSK_CONFIG.servers) { execute app.pull }
-    end
-
-    desc "Start app on servers"
-    task :start do
-      on(MRSK_CONFIG.servers) { execute app.start }
-    end
-
-    desc "Stop app on servers"
-    task :stop do
-      on(MRSK_CONFIG.servers) { execute app.stop, raise_on_non_zero_exit: false }
-    end
-
-    desc "Restart app on servers"
-    task restart: %i[ stop start ]
-
-    desc "Display information about app containers"
-    task :info do
-      on(MRSK_CONFIG.servers) { |host| puts "Host: #{host}\n" + capture(app.info) + "\n\n" }
-    end
-  end
-end

lib/tasks/mrsk/mrsk.rake

@@ -1,12 +0,0 @@
-namespace :mrsk do
-  desc "Push the latest version of the app, ensure Traefik is running, then restart app"
-  task deploy: [ "app:push", "traefik:start", "app:restart" ]
-
-  desc "Display information about Traefik and app containers"
-  task info: [ "traefik:info", "app:info" ]
-
-  desc "Create config stub"
-  task :init do
-    Rails.root.join("config/deploy.yml")
-  end
-end

lib/tasks/mrsk/registry.rake

@@ -1,13 +0,0 @@
-require_relative "setup"
-
-registry = Mrsk::Commands::Registry.new(MRSK_CONFIG)
-
-namespace :mrsk do
-  namespace :registry do
-    desc "Login to the registry locally and remotely"
-    task :login do
-      run_locally             { execute registry.login }
-      on(MRSK_CONFIG.servers) { execute registry.login }
-    end
-  end
-end

lib/tasks/mrsk/setup.rb

@@ -1,8 +0,0 @@
-require "sshkit"
-require "sshkit/dsl"
-
-include SSHKit::DSL
-
-MRSK_CONFIG = Mrsk::Configuration.load_file(Rails.root.join("config/deploy.yml"))
-
-SSHKit::Backend::Netssh.configure { |ssh| ssh.ssh_options = MRSK_CONFIG.ssh_options }

lib/tasks/mrsk/traefik.rake

@@ -1,25 +0,0 @@
-require_relative "setup"
-
-traefik = Mrsk::Commands::Traefik.new(MRSK_CONFIG)
-
-namespace :mrsk do
-  namespace :traefik do
-    desc "Start Traefik"
-    task :start do
-      on(MRSK_CONFIG.servers) { execute traefik.start, raise_on_non_zero_exit: false }
-    end
-
-    desc "Stop Traefik"
-    task :stop do
-      on(MRSK_CONFIG.servers) { execute traefik.stop, raise_on_non_zero_exit: false }
-    end
-
-    desc "Restart Traefik"
-    task restart: %i[ stop start ]
-
-    desc "Display information about Traefik containers"
-    task :info do
-      on(MRSK_CONFIG.servers) { |host| puts "Host: #{host}\n" + capture(traefik.info) + "\n\n" }
-    end
-  end
-end

mrsk.gemspec

@@ -6,11 +6,15 @@ Gem::Specification.new do |spec|
   spec.authors     = [ "David Heinemeier Hansson" ]
   spec.email       = "dhh@hey.com"
   spec.homepage    = "https://github.com/rails/mrsk"
-  spec.summary     = "Deploy Docker containers with zero downtime to any host."
+  spec.summary     = "Deploy web apps in containers to servers running Docker with zero downtime."
   spec.license     = "MIT"
 
   spec.files = Dir["lib/**/*", "MIT-LICENSE", "README.md"]
+  spec.executables = %w[ mrsk ]
 
-  spec.add_dependency "railties", ">= 7.0.0"
+  spec.add_dependency "activesupport", ">= 7.0"
   spec.add_dependency "sshkit", "~> 1.21"
+  spec.add_dependency "thor", "~> 1.2"
+  spec.add_dependency "dotenv", "~> 2.8"
+  spec.add_dependency "zeitwerk", "~> 2.5"
 end

test/cli/accessory_test.rb

@@ -0,0 +1,46 @@
+require_relative "cli_test_case"
+
+class CliAccessoryTest < CliTestCase
+  test "upload" do
+    assert_match "test/fixtures/files/my.cnf app-mysql/etc/mysql/my.cnf", run_command("upload", "mysql")
+  end
+
+  test "directories" do
+    assert_match "mkdir -p $PWD/app-mysql/data", run_command("directories", "mysql")
+  end
+
+  test "remove service direcotry" do
+    assert_match "rm -rf app-mysql", run_command("remove_service_directory", "mysql")
+  end
+
+  test "boot" do
+    assert_match "Running docker run --name app-mysql --detach --restart unless-stopped --log-opt max-size=10m --publish 3306:3306 -e [REDACTED] -e MYSQL_ROOT_HOST=\"%\" --volume $PWD/app-mysql/etc/mysql/my.cnf:/etc/mysql/my.cnf --volume $PWD/app-mysql/data:/var/lib/mysql --label service=\"app-mysql\" mysql:5.7 on 1.1.1.3", run_command("boot", "mysql")
+  end
+
+  test "exec" do
+    run_command("exec", "mysql", "mysql -v").tap do |output|
+      assert_match /Launching command from new container/, output
+      assert_match /mysql -v/, output
+    end
+  end
+
+  test "exec with reuse" do
+    run_command("exec", "mysql", "--reuse", "mysql -v").tap do |output|
+      assert_match /Launching command from existing container/, output
+      assert_match %r[docker exec app-mysql mysql -v], output
+    end
+  end
+
+  test "remove with confirmation" do
+    run_command("remove", "mysql", "-y").tap do |output|
+      assert_match /docker container stop app-mysql/, output
+      assert_match /docker image prune --all --force --filter label=service=app-mysql/, output
+      assert_match /rm -rf app-mysql/, output
+    end
+  end
+
+  private
+    def run_command(*command)
+      stdouted { Mrsk::Cli::Accessory.start([*command, "-c", "test/fixtures/deploy_with_accessories.yml"]) }
+    end
+end

test/cli/app_test.rb

@@ -0,0 +1,75 @@
+require_relative "cli_test_case"
+
+class CliAppTest < CliTestCase
+  test "boot" do
+    assert_match /Running docker run --detach --restart unless-stopped/, run_command("boot")
+  end
+
+  test "boot will reboot if same version is already running" do
+    run_command("details") # Preheat MRSK const
+
+    # Prevent expected failures from outputting to terminal
+    Thread.report_on_exception = false
+
+    MRSK.app.stubs(:run).raises(SSHKit::Command::Failed.new("already in use")).then.returns([ :docker, :run ])
+
+    run_command("boot").tap do |output|
+      assert_match /Rebooting container with same version already deployed/, output # Can't start what's already running
+      assert_match /docker ps --quiet --filter label=service=app \| xargs docker stop/, output # Stop what's running
+      assert_match /docker container ls --all --filter name=app-999 --quiet \| xargs docker container rm/, output # Remove old container
+      assert_match /docker run/, output # Start new container
+    end
+  ensure
+    Thread.report_on_exception = true
+  end
+
+  test "start" do
+    run_command("start").tap do |output|
+      assert_match /docker start app-999/, output
+    end
+  end
+
+  test "stop" do
+    run_command("stop").tap do |output|
+      assert_match /docker ps --quiet --filter label=service=app \| xargs docker stop/, output
+    end
+  end
+
+  test "details" do
+    run_command("details").tap do |output|
+      assert_match /docker ps --filter label=service=app/, output
+    end
+  end
+
+  test "remove" do
+    run_command("remove").tap do |output|
+      assert_match /docker ps --quiet --filter label=service=app | xargs docker stop/, output
+      assert_match /docker container prune --force --filter label=service=app/, output
+      assert_match /docker image prune --all --force --filter label=service=app/, output
+    end
+  end
+
+  test "remove_container" do
+    run_command("remove_container", "1234567").tap do |output|
+      assert_match /docker container ls --all --filter name=app-1234567 --quiet \| xargs docker container rm/, output
+    end
+  end
+
+  test "exec" do
+    run_command("exec", "ruby -v").tap do |output|
+      assert_match /ruby -v/, output
+    end
+  end
+
+  test "exec with reuse" do
+    run_command("exec", "--reuse", "ruby -v").tap do |output|
+      assert_match %r[docker ps --filter label=service=app --format \"{{.Names}}\" | sed 's/-/\\n/g' | tail -n 1], output # Get current version
+      assert_match %r[docker exec app-999 ruby -v], output
+    end
+  end
+
+  private
+    def run_command(*command)
+      stdouted { Mrsk::Cli::App.start([*command, "-c", "test/fixtures/deploy_with_accessories.yml"]) }
+    end
+end

test/cli/build_test.rb

@@ -0,0 +1,15 @@
+require_relative "cli_test_case"
+
+class CliBuildTest < CliTestCase
+  test "pull" do
+    run_command("pull").tap do |output|
+      assert_match /docker image rm --force dhh\/app:999/, output
+      assert_match /docker pull dhh\/app:999/, output
+    end
+  end
+
+  private
+    def run_command(*command)
+      stdouted { Mrsk::Cli::Build.start([*command, "-c", "test/fixtures/deploy_with_accessories.yml"]) }
+    end
+end

test/cli/cli_test_case.rb

@@ -0,0 +1,24 @@
+require "test_helper"
+require "active_support/testing/stream"
+
+class CliTestCase < ActiveSupport::TestCase
+  include ActiveSupport::Testing::Stream
+
+  setup do
+    ENV["VERSION"]             = "999"
+    ENV["RAILS_MASTER_KEY"]    = "123"
+    ENV["MYSQL_ROOT_PASSWORD"] = "secret123"
+  end
+
+  teardown do
+    ENV.delete("RAILS_MASTER_KEY")
+    ENV.delete("MYSQL_ROOT_PASSWORD")
+    ENV.delete("VERSION")
+    MRSK.reset
+  end
+
+  private
+    def stdouted
+      capture(:stdout) { yield }.strip
+    end
+end

test/cli/main_test.rb

@@ -0,0 +1,56 @@
+require_relative "cli_test_case"
+
+class CliMainTest < CliTestCase
+  test "version" do
+    version = stdouted { Mrsk::Cli::Main.new.version }
+    assert_equal Mrsk::VERSION, version
+  end
+
+  test "rollback bad version" do
+    run_command("details") # Preheat MRSK const
+
+    run_command("rollback", "nonsense").tap do |output|
+      assert_match /docker container ls --all --filter label=service=app --format '{{ .Names }}'/, output
+      assert_match /The app version 'nonsense' is not available as a container/, output
+    end
+  end
+
+  test "rollback good version" do
+    Mrsk::Cli::Main.any_instance.stubs(:container_name_available?).returns(true)
+
+    run_command("rollback", "123").tap do |output|
+      assert_match /Stop current version, then start version 123/, output
+      assert_match /docker ps -q --filter label=service=app | xargs docker stop/, output
+      assert_match /docker start app-123/, output
+    end
+  end
+
+  test "remove with confirmation" do
+    run_command("remove", "-y").tap do |output|
+      assert_match /docker container stop traefik/, output
+      assert_match /docker container prune --force --filter label=org.opencontainers.image.title=Traefik/, output
+      assert_match /docker image prune --all --force --filter label=org.opencontainers.image.title=Traefik/, output
+
+      assert_match /docker ps --quiet --filter label=service=app | xargs docker stop/, output
+      assert_match /docker container prune --force --filter label=service=app/, output
+      assert_match /docker image prune --all --force --filter label=service=app/, output
+
+      assert_match /docker container stop app-mysql/, output
+      assert_match /docker container prune --force --filter label=service=app-mysql/, output
+      assert_match /docker image prune --all --force --filter label=service=app-mysql/, output
+      assert_match /rm -rf app-mysql/, output
+
+      assert_match /docker container stop app-redis/, output
+      assert_match /docker container prune --force --filter label=service=app-redis/, output
+      assert_match /docker image prune --all --force --filter label=service=app-redis/, output
+      assert_match /rm -rf app-redis/, output
+
+      assert_match /docker logout/, output
+    end
+  end
+
+  private
+    def run_command(*command)
+      stdouted { Mrsk::Cli::Main.start([*command, "-c", "test/fixtures/deploy_with_accessories.yml"]) }
+    end
+end

test/commander_test.rb

@@ -0,0 +1,45 @@
+require "test_helper"
+
+class CommanderTest < ActiveSupport::TestCase
+  setup do
+    @mrsk = Mrsk::Commander.new config_file: Pathname.new(File.expand_path("fixtures/deploy_with_roles.yml", __dir__))
+  end
+
+  test "lazy configuration" do
+    assert_equal Mrsk::Configuration, @mrsk.config.class
+  end
+
+  test "commit hash as version" do
+    assert_equal `git rev-parse HEAD`.strip, @mrsk.config.version
+  end
+
+  test "commit hash as version but not in git" do
+    @mrsk.expects(:system).with("git rev-parse").returns(nil)
+    error = assert_raises(RuntimeError) { @mrsk.config }
+    assert_match /no git repository found/, error.message
+  end
+
+  test "overwriting hosts" do
+    assert_equal [ "1.1.1.1", "1.1.1.2", "1.1.1.3", "1.1.1.4" ], @mrsk.hosts
+
+    @mrsk.specific_hosts = [ "1.2.3.4", "1.2.3.5" ]
+    assert_equal [ "1.2.3.4", "1.2.3.5" ], @mrsk.hosts
+  end
+
+  test "overwriting hosts with roles" do
+    assert_equal [ "1.1.1.1", "1.1.1.2", "1.1.1.3", "1.1.1.4" ], @mrsk.hosts
+
+    @mrsk.specific_roles = [ "workers", "web" ]
+    assert_equal [ "1.1.1.1", "1.1.1.2", "1.1.1.3", "1.1.1.4" ], @mrsk.hosts
+
+    @mrsk.specific_roles = [ "workers" ]
+    assert_equal [ "1.1.1.3", "1.1.1.4" ], @mrsk.hosts
+  end
+
+  test "overwriting hosts with primary" do
+    assert_equal [ "1.1.1.1", "1.1.1.2", "1.1.1.3", "1.1.1.4" ], @mrsk.hosts
+
+    @mrsk.specific_primary!
+    assert_equal [ "1.1.1.1" ], @mrsk.hosts
+  end
+end

test/commands/accessory_test.rb

@@ -0,0 +1,134 @@
+require "test_helper"
+
+class CommandsAccessoryTest < ActiveSupport::TestCase
+  setup do
+    @config = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
+      servers: [ "1.1.1.1" ],
+      accessories: {
+        "mysql" => {
+          "image" => "mysql:8.0",
+          "host" => "1.1.1.5",
+          "port" => "3306",
+          "env" => {
+            "clear" => {
+              "MYSQL_ROOT_HOST" => "%"
+            },
+            "secret" => [
+              "MYSQL_ROOT_PASSWORD"
+            ]
+          }
+        },
+        "redis" => {
+          "image" => "redis:latest",
+          "host" => "1.1.1.6",
+          "port" => "6379:6379",
+          "labels" => {
+            "cache" => true
+          },
+          "env" => {
+            "SOMETHING" => "else"
+          },
+          "volumes" => [
+            "/var/lib/redis:/data"
+          ]
+        }
+      }
+    }
+
+    @config = Mrsk::Configuration.new(@config)
+    @mysql  = Mrsk::Commands::Accessory.new(@config, name: :mysql)
+    @redis  = Mrsk::Commands::Accessory.new(@config, name: :redis)
+
+    ENV["MYSQL_ROOT_PASSWORD"] = "secret123"
+  end
+
+  teardown do
+    ENV.delete("MYSQL_ROOT_PASSWORD")
+  end
+
+  test "run" do
+    assert_equal \
+      "docker run --name app-mysql --detach --restart unless-stopped --log-opt max-size=10m --publish 3306:3306 -e MYSQL_ROOT_PASSWORD=\"secret123\" -e MYSQL_ROOT_HOST=\"%\" --label service=\"app-mysql\" mysql:8.0",
+      @mysql.run.join(" ")
+
+    assert_equal \
+      "docker run --name app-redis --detach --restart unless-stopped --log-opt max-size=10m --publish 6379:6379 -e SOMETHING=\"else\" --volume /var/lib/redis:/data --label service=\"app-redis\" --label cache=\"true\" redis:latest",
+      @redis.run.join(" ")
+  end
+
+  test "start" do
+    assert_equal \
+      "docker container start app-mysql",
+      @mysql.start.join(" ")
+  end
+
+  test "stop" do
+    assert_equal \
+      "docker container stop app-mysql",
+      @mysql.stop.join(" ")
+  end
+
+  test "info" do
+    assert_equal \
+      "docker ps --filter label=service=app-mysql",
+      @mysql.info.join(" ")
+  end
+
+
+  test "execute in new container" do
+    assert_equal \
+      "docker run --rm -e MYSQL_ROOT_PASSWORD=\"secret123\" -e MYSQL_ROOT_HOST=\"%\" mysql:8.0 mysql -u root",
+      @mysql.execute_in_new_container("mysql", "-u", "root").join(" ")
+  end
+
+  test "execute in existing container" do
+    assert_equal \
+      "docker exec app-mysql mysql -u root",
+      @mysql.execute_in_existing_container("mysql", "-u", "root").join(" ")
+  end
+
+  test "execute in new container over ssh" do
+    @mysql.stub(:run_over_ssh, ->(cmd) { cmd.join(" ") }) do
+      assert_match %r|docker run -it --rm -e MYSQL_ROOT_PASSWORD=\"secret123\" -e MYSQL_ROOT_HOST=\"%\" mysql:8.0 mysql -u root|,
+        @mysql.execute_in_new_container_over_ssh("mysql", "-u", "root")
+    end
+  end
+
+  test "execute in existing container over ssh" do
+    @mysql.stub(:run_over_ssh, ->(cmd) { cmd.join(" ") }) do
+      assert_match %r|docker exec -it app-mysql mysql -u root|,
+        @mysql.execute_in_existing_container_over_ssh("mysql", "-u", "root")
+    end
+  end
+
+
+
+  test "logs" do
+    assert_equal \
+      "docker logs app-mysql --timestamps 2>&1",
+      @mysql.logs.join(" ")
+
+    assert_equal \
+      "docker logs app-mysql  --since 5m  --tail 100 --timestamps 2>&1 | grep 'thing'",
+      @mysql.logs(since: "5m", lines: 100, grep: "thing").join(" ")
+  end
+
+  test "follow logs" do
+    assert_equal \
+      "ssh -t root@1.1.1.5 'docker logs app-mysql --timestamps --tail 10 --follow 2>&1'",
+      @mysql.follow_logs
+  end
+
+  test "remove container" do
+    assert_equal \
+      "docker container prune --force --filter label=service=app-mysql",
+      @mysql.remove_container.join(" ")
+  end
+
+  test "remove image" do
+    assert_equal \
+      "docker image prune --all --force --filter label=service=app-mysql",
+      @mysql.remove_image.join(" ")
+  end
+end

test/commands/app_test.rb

@@ -0,0 +1,169 @@
+require "test_helper"
+
+class CommandsAppTest < ActiveSupport::TestCase
+  setup do
+    ENV["RAILS_MASTER_KEY"] = "456"
+
+    @config = { service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" }, servers: [ "1.1.1.1" ], env: { "secret" => [ "RAILS_MASTER_KEY" ] } }
+    @app = Mrsk::Commands::App.new Mrsk::Configuration.new(@config).tap { |c| c.version = "999" }
+  end
+
+  teardown do
+    ENV.delete("RAILS_MASTER_KEY")
+  end
+
+  test "run" do
+    assert_equal \
+      "docker run --detach --restart unless-stopped --log-opt max-size=10m --name app-999 -e RAILS_MASTER_KEY=\"456\" --label service=\"app\" --label role=\"web\" --label traefik.http.routers.app.rule=\"PathPrefix(\\`/\\`)\" --label traefik.http.services.app.loadbalancer.healthcheck.path=\"/up\" --label traefik.http.services.app.loadbalancer.healthcheck.interval=\"1s\" --label traefik.http.middlewares.app.retry.attempts=\"3\" --label traefik.http.middlewares.app.retry.initialinterval=\"500ms\" dhh/app:999",
+      @app.run.join(" ")
+  end
+
+  test "run with volumes" do
+    @config[:volumes] = ["/local/path:/container/path" ]
+
+    assert_equal \
+      "docker run --detach --restart unless-stopped --log-opt max-size=10m --name app-999 -e RAILS_MASTER_KEY=\"456\" --volume /local/path:/container/path --label service=\"app\" --label role=\"web\" --label traefik.http.routers.app.rule=\"PathPrefix(\\`/\\`)\" --label traefik.http.services.app.loadbalancer.healthcheck.path=\"/up\" --label traefik.http.services.app.loadbalancer.healthcheck.interval=\"1s\" --label traefik.http.middlewares.app.retry.attempts=\"3\" --label traefik.http.middlewares.app.retry.initialinterval=\"500ms\" dhh/app:999",
+      @app.run.join(" ")
+  end
+
+  test "run with custom healthcheck path" do
+    @config[:healthcheck] = { "path" => "/healthz" }
+
+    assert_equal \
+      "docker run --detach --restart unless-stopped --log-opt max-size=10m --name app-999 -e RAILS_MASTER_KEY=\"456\" --label service=\"app\" --label role=\"web\" --label traefik.http.routers.app.rule=\"PathPrefix(\\`/\\`)\" --label traefik.http.services.app.loadbalancer.healthcheck.path=\"/healthz\" --label traefik.http.services.app.loadbalancer.healthcheck.interval=\"1s\" --label traefik.http.middlewares.app.retry.attempts=\"3\" --label traefik.http.middlewares.app.retry.initialinterval=\"500ms\" dhh/app:999",
+      @app.run.join(" ")
+  end
+
+  test "start" do
+    assert_equal \
+      "docker start app-999",
+      @app.start.join(" ")
+  end
+
+  test "stop" do
+    assert_equal \
+      "docker ps --quiet --filter label=service=app | xargs docker stop",
+      @app.stop.join(" ")
+  end
+
+  test "info" do
+    assert_equal \
+      "docker ps --filter label=service=app",
+      @app.info.join(" ")
+  end
+
+
+  test "logs" do
+    assert_equal \
+      "docker ps --quiet --filter label=service=app | xargs docker logs 2>&1",
+      @app.logs.join(" ")
+
+    assert_equal \
+      "docker ps --quiet --filter label=service=app | xargs docker logs --since 5m 2>&1",
+      @app.logs(since: "5m").join(" ")
+
+    assert_equal \
+      "docker ps --quiet --filter label=service=app | xargs docker logs --tail 100 2>&1",
+      @app.logs(lines: "100").join(" ")
+
+    assert_equal \
+      "docker ps --quiet --filter label=service=app | xargs docker logs --since 5m --tail 100 2>&1",
+      @app.logs(since: "5m", lines: "100").join(" ")
+
+    assert_equal \
+      "docker ps --quiet --filter label=service=app | xargs docker logs 2>&1 | grep 'my-id'",
+      @app.logs(grep: "my-id").join(" ")
+
+    assert_equal \
+      "docker ps --quiet --filter label=service=app | xargs docker logs --since 5m 2>&1 | grep 'my-id'",
+      @app.logs(since: "5m", grep: "my-id").join(" ")
+  end
+
+  test "follow logs" do
+    @app.stub(:run_over_ssh, ->(cmd, host:) { cmd.join(" ") }) do
+      assert_equal \
+        "docker ps --quiet --filter label=service=app | xargs docker logs --timestamps --tail 10 --follow 2>&1",
+        @app.follow_logs(host: "app-1")
+
+      assert_equal \
+        "docker ps --quiet --filter label=service=app | xargs docker logs --timestamps --tail 10 --follow 2>&1 | grep \"Completed\"",
+        @app.follow_logs(host: "app-1", grep: "Completed")
+    end
+  end
+
+
+  test "execute in new container" do
+    assert_equal \
+      "docker run --rm -e RAILS_MASTER_KEY=\"456\" dhh/app:999 bin/rails db:setup",
+      @app.execute_in_new_container("bin/rails", "db:setup").join(" ")
+  end
+
+  test "execute in existing container" do
+    assert_equal \
+      "docker exec app-999 bin/rails db:setup",
+      @app.execute_in_existing_container("bin/rails", "db:setup").join(" ")
+  end
+
+  test "execute in new container over ssh" do
+    @app.stub(:run_over_ssh, ->(cmd, host:) { cmd.join(" ") }) do
+      assert_match %r|docker run -it --rm -e RAILS_MASTER_KEY=\"456\" dhh/app:999 bin/rails c|,
+        @app.execute_in_new_container_over_ssh("bin/rails", "c", host: "app-1")
+    end
+  end
+
+  test "execute in existing container over ssh" do
+    @app.stub(:run_over_ssh, ->(cmd, host:) { cmd.join(" ") }) do
+      assert_match %r|docker exec -it app-999 bin/rails c|,
+        @app.execute_in_existing_container_over_ssh("bin/rails", "c", host: "app-1")
+    end
+  end
+
+  test "run over ssh" do
+    assert_equal "ssh -t root@1.1.1.1 'ls'", @app.run_over_ssh("ls", host: "1.1.1.1")
+  end
+
+  test "run over ssh with custom user" do
+    @app = Mrsk::Commands::App.new Mrsk::Configuration.new(@config.tap { |c| c[:ssh] = { "user" => "app" } })
+    assert_equal "ssh -t app@1.1.1.1 'ls'", @app.run_over_ssh("ls", host: "1.1.1.1")
+  end
+
+  test "run over ssh with proxy" do
+    @app = Mrsk::Commands::App.new Mrsk::Configuration.new(@config.tap { |c| c[:ssh] = { "proxy" => "2.2.2.2" } })
+    assert_equal "ssh -J root@2.2.2.2 -t root@1.1.1.1 'ls'", @app.run_over_ssh("ls", host: "1.1.1.1")
+  end
+
+  test "run over ssh with proxy user" do
+    @app = Mrsk::Commands::App.new Mrsk::Configuration.new(@config.tap { |c| c[:ssh] = { "proxy" => "app@2.2.2.2" } })
+    assert_equal "ssh -J app@2.2.2.2 -t root@1.1.1.1 'ls'", @app.run_over_ssh("ls", host: "1.1.1.1")
+  end
+
+  test "run over ssh with custom user with proxy" do
+    @app = Mrsk::Commands::App.new Mrsk::Configuration.new(@config.tap { |c| c[:ssh] = { "user" => "app", "proxy" => "2.2.2.2" } })
+    assert_equal "ssh -J root@2.2.2.2 -t app@1.1.1.1 'ls'", @app.run_over_ssh("ls", host: "1.1.1.1")
+  end
+
+
+  test "current_container_id" do
+    assert_equal \
+      "docker ps --quiet --filter label=service=app",
+      @app.current_container_id.join(" ")
+  end
+
+  test "container_id_for" do
+    assert_equal \
+      "docker container ls --all --filter name=app-999 --quiet",
+      @app.container_id_for(container_name: "app-999").join(" ")
+  end
+
+  test "current_running_version" do
+    assert_equal \
+      "docker ps --filter label=service=app --format \"{{.Names}}\" | sed 's/-/\\n/g' | tail -n 1",
+      @app.current_running_version.join(" ")
+  end
+
+  test "most_recent_version_from_available_images" do
+    assert_equal \
+      "docker image ls --format \"{{.Tag}}\" dhh/app | head -n 1",
+      @app.most_recent_version_from_available_images.join(" ")
+  end
+end

test/commands/auditor_test.rb

@@ -0,0 +1,27 @@
+require "test_helper"
+
+class CommandsAuditorTest < ActiveSupport::TestCase
+  setup do
+    @config = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" }, servers: [ "1.1.1.1" ],
+      audit_broadcast_cmd: "bin/audit_broadcast"
+    }
+  end
+
+  test "record" do
+    assert_match \
+      /echo '.* app removed container' >> mrsk-app-audit.log/,
+      new_command.record("app removed container").join(" ")
+  end
+
+  test "broadcast" do
+    assert_match \
+      /bin\/audit_broadcast '\[.*\] app removed container'/,
+      new_command.broadcast("app removed container").join(" ")
+  end
+
+  private
+    def new_command
+      Mrsk::Commands::Auditor.new(Mrsk::Configuration.new(@config, version: "123"))
+    end
+end

test/commands/builder_test.rb

@@ -0,0 +1,79 @@
+require "test_helper"
+
+class CommandsBuilderTest < ActiveSupport::TestCase
+  setup do
+    @config = { service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" }, servers: [ "1.1.1.1" ] }
+  end
+
+  test "target multiarch by default" do
+    builder = new_builder_command
+    assert_equal "multiarch", builder.name
+    assert_equal \
+      "docker buildx build --push --platform linux/amd64,linux/arm64 --builder mrsk-app-multiarch -t dhh/app:123 -t dhh/app:latest --label service=\"app\" .",
+      builder.push.join(" ")
+  end
+
+  test "target native when multiarch is off" do
+    builder = new_builder_command(builder: { "multiarch" => false })
+    assert_equal "native", builder.name
+    assert_equal \
+      "docker build -t dhh/app:123 -t dhh/app:latest --label service=\"app\" . && docker push dhh/app:123",
+      builder.push.join(" ")
+  end
+
+  test "target multiarch remote when local and remote is set" do
+    builder = new_builder_command(builder: { "local" => { }, "remote" => { } })
+    assert_equal "multiarch/remote", builder.name
+    assert_equal \
+      "docker buildx build --push --platform linux/amd64,linux/arm64 --builder mrsk-app-multiarch-remote -t dhh/app:123 -t dhh/app:latest --label service=\"app\" .",
+      builder.push.join(" ")
+  end
+
+  test "target native remote when only remote is set" do
+    builder = new_builder_command(builder: { "remote" => { "arch" => "amd64" } })
+    assert_equal "native/remote", builder.name
+    assert_equal \
+      "docker buildx build --push --platform linux/amd64 --builder mrsk-app-native-remote -t dhh/app:123 -t dhh/app:latest --label service=\"app\" .",
+      builder.push.join(" ")
+  end
+
+  test "build args" do
+    builder = new_builder_command(builder: { "args" => { "a" => 1, "b" => 2 } })
+    assert_equal \
+      "-t dhh/app:123 -t dhh/app:latest --label service=\"app\" --build-arg a=\"1\" --build-arg b=\"2\"",
+      builder.target.build_options.join(" ")
+  end
+
+  test "build secrets" do
+    builder = new_builder_command(builder: { "secrets" => ["token_a", "token_b"] })
+    assert_equal \
+      "-t dhh/app:123 -t dhh/app:latest --label service=\"app\" --secret id=\"token_a\" --secret id=\"token_b\"",
+      builder.target.build_options.join(" ")
+  end
+
+  test "native push with build args" do
+    builder = new_builder_command(builder: { "multiarch" => false, "args" => { "a" => 1, "b" => 2 } })
+    assert_equal \
+      "docker build -t dhh/app:123 -t dhh/app:latest --label service=\"app\" --build-arg a=\"1\" --build-arg b=\"2\" . && docker push dhh/app:123",
+      builder.push.join(" ")
+  end
+
+  test "multiarch push with build args" do
+    builder = new_builder_command(builder: { "args" => { "a" => 1, "b" => 2 } })
+    assert_equal \
+      "docker buildx build --push --platform linux/amd64,linux/arm64 --builder mrsk-app-multiarch -t dhh/app:123 -t dhh/app:latest --label service=\"app\" --build-arg a=\"1\" --build-arg b=\"2\" .",
+      builder.push.join(" ")
+  end
+
+  test "native push with with build secrets" do
+    builder = new_builder_command(builder: { "multiarch" => false, "secrets" => [ "a", "b" ] })
+    assert_equal \
+      "docker build -t dhh/app:123 -t dhh/app:latest --label service=\"app\" --secret id=\"a\" --secret id=\"b\" . && docker push dhh/app:123",
+      builder.push.join(" ")
+  end
+
+  private
+    def new_builder_command(additional_config = {})
+      Mrsk::Commands::Builder.new(Mrsk::Configuration.new(@config.merge(additional_config), version: "123"))
+    end
+end

test/commands/healthcheck_test.rb

@@ -0,0 +1,55 @@
+require "test_helper"
+
+class CommandsHealthcheckTest < ActiveSupport::TestCase
+  setup do
+    @config = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" }, servers: [ "1.1.1.1" ],
+      traefik: { "args" => { "accesslog.format" => "json", "metrics.prometheus.buckets" => "0.1,0.3,1.2,5.0" } }
+    }
+  end
+
+  test "run" do
+    assert_equal \
+      "docker run --detach --name healthcheck-app-123 --publish 3999:3000 --label service=healthcheck-app dhh/app:123",
+      new_command.run.join(" ")
+  end
+
+  test "run with custom port" do
+    @config[:healthcheck] = { "port" => 3001 }
+
+    assert_equal \
+      "docker run --detach --name healthcheck-app-123 --publish 3999:3001 --label service=healthcheck-app dhh/app:123",
+      new_command.run.join(" ")
+  end
+
+  test "curl" do
+    assert_equal \
+      "curl --silent --output /dev/null --write-out '%{http_code}' --max-time 2 http://localhost:3999/up",
+      new_command.curl.join(" ")
+  end
+
+  test "curl with custom path" do
+    @config[:healthcheck] = { "path" => "/healthz" }
+
+    assert_equal \
+      "curl --silent --output /dev/null --write-out '%{http_code}' --max-time 2 http://localhost:3999/healthz",
+      new_command.curl.join(" ")
+  end
+
+  test "stop" do
+    assert_equal \
+      "docker container ls --all --filter name=healthcheck-app --quiet | xargs docker stop",
+      new_command.stop.join(" ")
+  end
+
+  test "remove" do
+    assert_equal \
+      "docker container ls --all --filter name=healthcheck-app --quiet | xargs docker container rm",
+      new_command.remove.join(" ")
+  end
+
+  private
+    def new_command
+      Mrsk::Commands::Healthcheck.new(Mrsk::Configuration.new(@config, version: "123"))
+    end
+end

test/commands/prune_test.rb

@@ -0,0 +1,27 @@
+require "test_helper"
+
+class CommandsPruneTest < ActiveSupport::TestCase
+  setup do
+    @config = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" }, servers: [ "1.1.1.1" ],
+      traefik: { "args" => { "accesslog.format" => "json", "metrics.prometheus.buckets" => "0.1,0.3,1.2,5.0" } }
+    }
+  end
+
+  test "images" do
+    assert_equal \
+      "docker image prune --all --force --filter label=service=app --filter until=168h",
+      new_command.images.join(" ")
+  end
+
+  test "containers" do
+    assert_equal \
+      "docker container prune --force --filter label=service=app --filter until=72h",
+      new_command.containers.join(" ")
+  end
+
+  private
+    def new_command
+      Mrsk::Commands::Prune.new(Mrsk::Configuration.new(@config, version: "123"))
+    end
+end

test/commands/registry_test.rb

@@ -0,0 +1,38 @@
+require "test_helper"
+
+class CommandsRegistryTest < ActiveSupport::TestCase
+  setup do
+    @config = { service: "app",
+      image: "dhh/app",
+      registry: { "username" => "dhh",
+        "password" => "secret",
+        "server" => "hub.docker.com"
+      },
+      servers: [ "1.1.1.1" ]
+    }
+    @registry = Mrsk::Commands::Registry.new Mrsk::Configuration.new(@config)
+  end
+
+  test "registry login" do
+    assert_equal \
+      "docker login hub.docker.com -u dhh -p secret",
+      @registry.login.join(" ")
+  end
+
+  test "registry login with ENV password" do
+    ENV["MRSK_REGISTRY_PASSWORD"] = "more-secret"
+    @config[:registry]["password"] = [ "MRSK_REGISTRY_PASSWORD" ]
+
+    assert_equal \
+      "docker login hub.docker.com -u dhh -p more-secret",
+      @registry.login.join(" ")
+  ensure
+    ENV.delete("MRSK_REGISTRY_PASSWORD")
+  end
+
+  test "registry logout" do
+    assert_equal \
+      "docker logout hub.docker.com",
+      @registry.logout.join(" ")
+  end
+end

test/commands/traefik_test.rb

@@ -0,0 +1,87 @@
+require "test_helper"
+
+class CommandsTraefikTest < ActiveSupport::TestCase
+  setup do
+    @config = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" }, servers: [ "1.1.1.1" ],
+      traefik: { "args" => { "accesslog.format" => "json", "metrics.prometheus.buckets" => "0.1,0.3,1.2,5.0" } }
+    }
+  end
+
+  test "run" do
+    assert_equal \
+      "docker run --name traefik --detach --restart unless-stopped --log-opt max-size=10m --publish 80:80 --volume /var/run/docker.sock:/var/run/docker.sock traefik --providers.docker --log.level=DEBUG --accesslog.format json --metrics.prometheus.buckets 0.1,0.3,1.2,5.0",
+      new_command.run.join(" ")
+  end
+
+  test "traefik start" do
+    assert_equal \
+      "docker container start traefik",
+      new_command.start.join(" ")
+  end
+
+  test "traefik stop" do
+    assert_equal \
+      "docker container stop traefik",
+      new_command.stop.join(" ")
+  end
+
+  test "traefik info" do
+    assert_equal \
+      "docker ps --filter name=traefik",
+      new_command.info.join(" ")
+  end
+
+  test "traefik logs" do
+    assert_equal \
+      "docker logs traefik --timestamps 2>&1",
+      new_command.logs.join(" ")
+  end
+
+  test "traefik logs since 2h" do
+    assert_equal \
+      "docker logs traefik  --since 2h --timestamps 2>&1",
+      new_command.logs(since: '2h').join(" ")
+  end
+
+  test "traefik logs last 10 lines" do
+    assert_equal \
+      "docker logs traefik  --tail 10 --timestamps 2>&1",
+      new_command.logs(lines: 10).join(" ")
+  end
+
+  test "traefik logs with grep hello!" do
+    assert_equal \
+      "docker logs traefik --timestamps 2>&1 | grep 'hello!'",
+      new_command.logs(grep: 'hello!').join(" ")
+  end
+
+  test "traefik remove container" do
+    assert_equal \
+      "docker container prune --force --filter label=org.opencontainers.image.title=Traefik",
+      new_command.remove_container.join(" ")
+  end
+
+  test "traefik remove image" do
+    assert_equal \
+      "docker image prune --all --force --filter label=org.opencontainers.image.title=Traefik",
+      new_command.remove_image.join(" ")
+  end
+
+  test "traefik follow logs" do
+    assert_equal \
+      "ssh -t root@1.1.1.1 'docker logs traefik --timestamps --tail 10 --follow 2>&1'",
+      new_command.follow_logs(host: @config[:servers].first)
+  end
+
+  test "traefik follow logs with grep hello!" do
+    assert_equal \
+      "ssh -t root@1.1.1.1 'docker logs traefik --timestamps --tail 10 --follow 2>&1 | grep \"hello!\"'",
+      new_command.follow_logs(host: @config[:servers].first, grep: 'hello!')
+  end
+
+  private
+    def new_command
+      Mrsk::Commands::Traefik.new(Mrsk::Configuration.new(@config, version: "123"))
+    end
+end

test/configuration/accessory_test.rb

@@ -0,0 +1,107 @@
+require "test_helper"
+
+class ConfigurationAccessoryTest < ActiveSupport::TestCase
+  setup do
+    @deploy = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
+      servers: [ "1.1.1.1", "1.1.1.2" ],
+      env: { "REDIS_URL" => "redis://x/y" },
+      accessories: {
+        "mysql" => {
+          "image" => "mysql:8.0",
+          "host" => "1.1.1.5",
+          "port" => "3306",
+          "env" => {
+            "clear" => {
+              "MYSQL_ROOT_HOST" => "%"
+            },
+            "secret" => [
+              "MYSQL_ROOT_PASSWORD"
+            ],
+          },
+          "files" => [
+            "config/mysql/my.cnf:/etc/mysql/my.cnf",
+            "db/structure.sql:/docker-entrypoint-initdb.d/structure.sql"
+          ],
+          "directories" => [
+            "data:/var/lib/mysql"
+          ]
+        },
+        "redis" => {
+          "image" => "redis:latest",
+          "host" => "1.1.1.6",
+          "port" => "6379:6379",
+          "labels" => {
+            "cache" => true
+          },
+          "env" => {
+            "SOMETHING" => "else"
+          },
+          "volumes" => [
+            "/var/lib/redis:/data"
+          ]
+        }
+      }
+    }
+
+    @config = Mrsk::Configuration.new(@deploy)
+  end
+
+  test "service name" do
+    assert_equal "app-mysql", @config.accessory(:mysql).service_name
+    assert_equal "app-redis", @config.accessory(:redis).service_name
+  end
+
+  test "port" do
+    assert_equal "3306:3306", @config.accessory(:mysql).port
+    assert_equal "6379:6379", @config.accessory(:redis).port
+  end
+
+  test "host" do
+    assert_equal "1.1.1.5", @config.accessory(:mysql).host
+    assert_equal "1.1.1.6", @config.accessory(:redis).host
+  end
+
+  test "missing host" do
+    @deploy[:accessories]["mysql"]["host"] = nil
+    @config = Mrsk::Configuration.new(@deploy)
+
+    assert_raises(ArgumentError) do
+      @config.accessory(:mysql).host
+    end
+  end
+
+  test "label args" do
+    assert_equal ["--label", "service=\"app-mysql\""], @config.accessory(:mysql).label_args
+    assert_equal ["--label", "service=\"app-redis\"", "--label", "cache=\"true\""], @config.accessory(:redis).label_args
+  end
+
+  test "env args with secret" do
+    ENV["MYSQL_ROOT_PASSWORD"] = "secret123"
+    assert_equal ["-e", "MYSQL_ROOT_PASSWORD=\"secret123\"", "-e", "MYSQL_ROOT_HOST=\"%\""], @config.accessory(:mysql).env_args
+    assert @config.accessory(:mysql).env_args[1].is_a?(SSHKit::Redaction)
+  ensure
+    ENV["MYSQL_ROOT_PASSWORD"] = nil
+  end
+
+  test "env args without secret" do
+    assert_equal ["-e", "SOMETHING=\"else\""], @config.accessory(:redis).env_args
+  end
+
+  test "volume args" do
+    assert_equal ["--volume", "$PWD/app-mysql/etc/mysql/my.cnf:/etc/mysql/my.cnf", "--volume", "$PWD/app-mysql/docker-entrypoint-initdb.d/structure.sql:/docker-entrypoint-initdb.d/structure.sql", "--volume", "$PWD/app-mysql/data:/var/lib/mysql"], @config.accessory(:mysql).volume_args
+    assert_equal ["--volume", "/var/lib/redis:/data"], @config.accessory(:redis).volume_args
+  end
+
+  test "dynamic file expansion" do
+    @deploy[:accessories]["mysql"]["files"] << "test/fixtures/files/structure.sql.erb:/docker-entrypoint-initdb.d/structure.sql"
+    @config = Mrsk::Configuration.new(@deploy)
+
+    assert_match "This was dynamically expanded", @config.accessory(:mysql).files.keys[2].read
+    assert_match "%", @config.accessory(:mysql).files.keys[2].read
+  end
+
+  test "directories" do
+    assert_equal({"$PWD/app-mysql/data"=>"/var/lib/mysql"}, @config.accessory(:mysql).directories)
+  end
+end

test/configuration/role_test.rb

@@ -0,0 +1,140 @@
+require "test_helper"
+
+class ConfigurationRoleTest < ActiveSupport::TestCase
+  setup do
+    @deploy = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
+      servers: [ "1.1.1.1", "1.1.1.2" ],
+      env: { "REDIS_URL" => "redis://x/y" }
+    }
+
+    @config = Mrsk::Configuration.new(@deploy)
+
+    @deploy_with_roles = @deploy.dup.merge({
+      servers: {
+        "web" => [ "1.1.1.1", "1.1.1.2" ],
+        "workers" => {
+          "hosts" => [ "1.1.1.3", "1.1.1.4" ],
+          "cmd" => "bin/jobs",
+          "env" => {
+            "REDIS_URL" => "redis://a/b",
+            "WEB_CONCURRENCY" => 4
+          }
+        }
+      }
+    })
+
+    @config_with_roles = Mrsk::Configuration.new(@deploy_with_roles)
+  end
+
+  test "hosts" do
+    assert_equal [ "1.1.1.1", "1.1.1.2" ], @config.role(:web).hosts
+    assert_equal [ "1.1.1.3", "1.1.1.4" ], @config_with_roles.role(:workers).hosts
+  end
+
+  test "cmd" do
+    assert_nil @config.role(:web).cmd
+    assert_equal "bin/jobs", @config_with_roles.role(:workers).cmd
+  end
+
+  test "label args" do
+    assert_equal [ "--label", "service=\"app\"", "--label", "role=\"workers\"" ], @config_with_roles.role(:workers).label_args
+  end
+
+  test "special label args for web" do
+    assert_equal [ "--label", "service=\"app\"", "--label", "role=\"web\"", "--label", "traefik.http.routers.app.rule=\"PathPrefix(\\`/\\`)\"", "--label", "traefik.http.services.app.loadbalancer.healthcheck.path=\"/up\"", "--label", "traefik.http.services.app.loadbalancer.healthcheck.interval=\"1s\"", "--label", "traefik.http.middlewares.app.retry.attempts=\"3\"", "--label", "traefik.http.middlewares.app.retry.initialinterval=\"500ms\""], @config.role(:web).label_args
+  end
+
+  test "custom labels" do
+    @deploy[:labels] = { "my.custom.label" => "50" }
+    assert_equal "50", @config.role(:web).labels["my.custom.label"]
+  end
+
+  test "custom labels via role specialization" do
+    @deploy_with_roles[:labels] = { "my.custom.label" => "50" }
+    @deploy_with_roles[:servers]["workers"]["labels"] = { "my.custom.label" => "70" }
+    assert_equal "70", @config_with_roles.role(:workers).labels["my.custom.label"]
+  end
+
+  test "overwriting default traefik label" do
+    @deploy[:labels] = { "traefik.http.routers.app.rule" => "\"Host(\\`example.com\\`) || (Host(\\`example.org\\`) && Path(\\`/traefik\\`))\"" }
+    assert_equal "\"Host(\\`example.com\\`) || (Host(\\`example.org\\`) && Path(\\`/traefik\\`))\"", @config.role(:web).labels["traefik.http.routers.app.rule"]
+  end
+
+  test "default traefik label on non-web role" do
+    config = Mrsk::Configuration.new(@deploy_with_roles.tap { |c|
+      c[:servers]["beta"] = { "traefik" => "true", "hosts" => [ "1.1.1.5" ] }
+    })
+
+    assert_equal [ "--label", "service=\"app\"", "--label", "role=\"beta\"", "--label", "traefik.http.routers.app.rule=\"PathPrefix(\\`/\\`)\"", "--label", "traefik.http.services.app.loadbalancer.healthcheck.path=\"/up\"", "--label", "traefik.http.services.app.loadbalancer.healthcheck.interval=\"1s\"", "--label", "traefik.http.middlewares.app.retry.attempts=\"3\"", "--label", "traefik.http.middlewares.app.retry.initialinterval=\"500ms\"" ], config.role(:beta).label_args
+  end
+
+  test "env overwritten by role" do
+    assert_equal "redis://a/b", @config_with_roles.role(:workers).env["REDIS_URL"]
+    assert_equal ["-e", "REDIS_URL=\"redis://a/b\"", "-e", "WEB_CONCURRENCY=\"4\""], @config_with_roles.role(:workers).env_args
+  end
+
+  test "env secret overwritten by role" do
+    @deploy_with_roles[:env] = {
+      "clear" => {
+        "REDIS_URL" => "redis://a/b"
+      },
+      "secret" => [
+        "REDIS_PASSWORD"
+      ]
+    }
+
+    @deploy_with_roles[:servers]["workers"]["env"] = {
+      "clear" => {
+        "REDIS_URL" => "redis://a/b",
+        "WEB_CONCURRENCY" => 4
+      },
+      "secret" => [
+        "DB_PASSWORD"
+      ]
+    }
+
+    ENV["REDIS_PASSWORD"] = "secret456"
+    ENV["DB_PASSWORD"] = "secret&\"123"
+
+    assert_equal ["-e", "REDIS_PASSWORD=\"secret456\"", "-e", "DB_PASSWORD=\"secret&\\\"123\"", "-e", "REDIS_URL=\"redis://a/b\"", "-e", "WEB_CONCURRENCY=\"4\""], @config_with_roles.role(:workers).env_args
+  ensure
+    ENV["REDIS_PASSWORD"] = nil
+    ENV["DB_PASSWORD"] = nil
+  end
+
+  test "env secrets only in role" do
+    @deploy_with_roles[:servers]["workers"]["env"] = {
+      "clear" => {
+        "REDIS_URL" => "redis://a/b",
+        "WEB_CONCURRENCY" => 4
+      },
+      "secret" => [
+        "DB_PASSWORD"
+      ]
+    }
+
+    ENV["DB_PASSWORD"] = "secret123"
+
+    assert_equal ["-e", "DB_PASSWORD=\"secret123\"", "-e", "REDIS_URL=\"redis://a/b\"", "-e", "WEB_CONCURRENCY=\"4\""], @config_with_roles.role(:workers).env_args
+  ensure
+    ENV["DB_PASSWORD"] = nil
+  end
+
+  test "env secrets only at top level" do
+    @deploy_with_roles[:env] = {
+      "clear" => {
+        "REDIS_URL" => "redis://a/b"
+      },
+      "secret" => [
+        "REDIS_PASSWORD"
+      ]
+    }
+
+    ENV["REDIS_PASSWORD"] = "secret456"
+
+    assert_equal ["-e", "REDIS_PASSWORD=\"secret456\"", "-e", "REDIS_URL=\"redis://a/b\"", "-e", "WEB_CONCURRENCY=\"4\""], @config_with_roles.role(:workers).env_args
+  ensure
+    ENV["REDIS_PASSWORD"] = nil
+  end
+end

test/configuration_test.rb

@@ -1,29 +1,186 @@
 require "test_helper"
-require "mrsk/configuration"
-
-ENV["VERSION"] = "123"
 
 class ConfigurationTest < ActiveSupport::TestCase
   setup do
-    @config = { service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" } }
+    ENV["RAILS_MASTER_KEY"] = "456"
+
+    @deploy = {
+      service: "app", image: "dhh/app",
+      registry: { "username" => "dhh", "password" => "secret" },
+      env: { "REDIS_URL" => "redis://x/y" },
+      servers: [ "1.1.1.1", "1.1.1.2" ],
+      volumes: ["/local/path:/container/path"]
+    }
+
+    @config = Mrsk::Configuration.new(@deploy)
+
+    @deploy_with_roles = @deploy.dup.merge({
+      servers: { "web" => [ "1.1.1.1", "1.1.1.2" ], "workers" => { "hosts" => [ "1.1.1.3", "1.1.1.4" ] } } })
+
+    @config_with_roles = Mrsk::Configuration.new(@deploy_with_roles)
+  end
+
+  teardown do
+    ENV["RAILS_MASTER_KEY"] = nil
   end
 
   test "ensure valid keys" do
     assert_raise(ArgumentError) do
-      Mrsk::Configuration.new(@config.tap { _1.delete(:service) })
-      Mrsk::Configuration.new(@config.tap { _1.delete(:image) })
-      Mrsk::Configuration.new(@config.tap { _1.delete(:registry) })
+      Mrsk::Configuration.new(@deploy.tap { _1.delete(:service) })
+      Mrsk::Configuration.new(@deploy.tap { _1.delete(:image) })
+      Mrsk::Configuration.new(@deploy.tap { _1.delete(:registry) })
 
-      Mrsk::Configuration.new(@config.tap { _1[:registry].delete("username") })
-      Mrsk::Configuration.new(@config.tap { _1[:registry].delete("password") })
+      Mrsk::Configuration.new(@deploy.tap { _1[:registry].delete("username") })
+      Mrsk::Configuration.new(@deploy.tap { _1[:registry].delete("password") })
     end
   end
 
-  test "absolute image" do
-    configuration = Mrsk::Configuration.new(@config)
-    assert_equal "dhh/app:123", configuration.absolute_image
+  test "roles" do
+    assert_equal %w[ web ], @config.roles.collect(&:name)
+    assert_equal %w[ web workers ], @config_with_roles.roles.collect(&:name)
+  end
 
-    configuration = Mrsk::Configuration.new(@config.tap { |c| c[:registry].merge!({ "server" => "ghcr.io" }) })
-    assert_equal "ghcr.io/dhh/app:123", configuration.absolute_image
+  test "role" do
+    assert_equal "web", @config.role(:web).name
+    assert_equal "workers", @config_with_roles.role(:workers).name
+    assert_nil @config.role(:missing)
+  end
+
+  test "all hosts" do
+    assert_equal [ "1.1.1.1", "1.1.1.2"], @config.all_hosts
+    assert_equal [ "1.1.1.1", "1.1.1.2", "1.1.1.3", "1.1.1.4" ], @config_with_roles.all_hosts
+  end
+
+  test "primary web host" do
+    assert_equal "1.1.1.1", @config.primary_web_host
+    assert_equal "1.1.1.1", @config_with_roles.primary_web_host
+  end
+
+  test "traefik hosts" do
+    assert_equal [ "1.1.1.1", "1.1.1.2" ], @config_with_roles.traefik_hosts
+
+    @deploy_with_roles[:servers]["workers"]["traefik"] = true
+    config = Mrsk::Configuration.new(@deploy_with_roles)
+
+    assert_equal [ "1.1.1.1", "1.1.1.2", "1.1.1.3", "1.1.1.4" ], config.traefik_hosts
+  end
+
+  test "version" do
+    assert_equal "missing", @config.version
+    assert_equal "123", Mrsk::Configuration.new(@deploy, version: "123").version
+  end
+
+  test "repository" do
+    assert_equal "dhh/app", @config.repository
+
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c[:registry].merge!({ "server" => "ghcr.io" }) })
+    assert_equal "ghcr.io/dhh/app", config.repository
+  end
+
+  test "absolute image" do
+    assert_equal "dhh/app:missing", @config.absolute_image
+
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c[:registry].merge!({ "server" => "ghcr.io" }) })
+    assert_equal "ghcr.io/dhh/app:missing", config.absolute_image
+  end
+
+  test "service with version" do
+    assert_equal "app-missing", @config.service_with_version
+  end
+
+  test "env args" do
+    assert_equal [ "-e", "REDIS_URL=\"redis://x/y\"" ], @config.env_args
+  end
+
+  test "env args with clear and secrets" do
+    ENV["PASSWORD"] = "secret123"
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c.merge!({
+      env: { "clear" => { "PORT" => "3000" }, "secret" => [ "PASSWORD" ] }
+    }) })
+
+    assert_equal [ "-e", "PASSWORD=\"secret123\"", "-e", "PORT=\"3000\"" ], config.env_args
+    assert config.env_args[1].is_a?(SSHKit::Redaction)
+  ensure
+    ENV["PASSWORD"] = nil
+  end
+
+  test "env args with only clear" do
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c.merge!({
+      env: { "clear" => { "PORT" => "3000" } }
+    }) })
+
+    assert_equal [ "-e", "PORT=\"3000\"" ], config.env_args
+  end
+
+  test "env args with only secrets" do
+    ENV["PASSWORD"] = "secret123"
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c.merge!({
+      env: { "secret" => [ "PASSWORD" ] }
+    }) })
+
+    assert_equal [ "-e", "PASSWORD=\"secret123\"" ], config.env_args
+    assert config.env_args[1].is_a?(SSHKit::Redaction)
+  ensure
+    ENV["PASSWORD"] = nil
+  end
+
+  test "env args with missing secret" do
+    assert_raises(KeyError) do
+      config = Mrsk::Configuration.new(@deploy.tap { |c| c.merge!({
+        env: { "secret" => [ "PASSWORD" ] }
+      }) })
+    end
+  end
+
+  test "valid config" do
+    assert @config.valid?
+  end
+
+  test "ssh options" do
+    assert_equal "root", @config.ssh_options[:user]
+
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c.merge!(ssh: { "user" => "app" }) })
+    assert_equal "app", @config.ssh_options[:user]
+  end
+
+  test "ssh options with proxy host" do
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c.merge!(ssh: { "proxy" => "1.2.3.4" }) })
+    assert_equal "root@1.2.3.4", @config.ssh_options[:proxy].jump_proxies
+  end
+
+  test "ssh options with proxy host and user" do
+    config = Mrsk::Configuration.new(@deploy.tap { |c| c.merge!(ssh: { "proxy" => "app@1.2.3.4" }) })
+    assert_equal "app@1.2.3.4", @config.ssh_options[:proxy].jump_proxies
+  end
+
+  test "volume_args" do
+    assert_equal ["--volume", "/local/path:/container/path"], @config.volume_args
+  end
+
+  test "erb evaluation of yml config" do
+    config = Mrsk::Configuration.create_from Pathname.new(File.expand_path("fixtures/deploy.erb.yml", __dir__))
+    assert_equal "my-user", config.registry["username"]
+  end
+
+  test "destination yml config merge" do
+    dest_config_file = Pathname.new(File.expand_path("fixtures/deploy_for_dest.yml", __dir__))
+
+    config = Mrsk::Configuration.create_from dest_config_file, destination: "world"
+    assert_equal "1.1.1.1", config.all_hosts.first
+
+    config = Mrsk::Configuration.create_from dest_config_file, destination: "mars"
+    assert_equal "1.1.1.3", config.all_hosts.first
+  end
+
+  test "destination yml config file missing" do
+    dest_config_file = Pathname.new(File.expand_path("fixtures/deploy_for_dest.yml", __dir__))
+
+    assert_raises(RuntimeError) do
+      config = Mrsk::Configuration.create_from dest_config_file, destination: "missing"
+    end
+  end
+
+  test "to_h" do
+    assert_equal({ :roles=>["web"], :hosts=>["1.1.1.1", "1.1.1.2"], :primary_host=>"1.1.1.1", :version=>"missing", :repository=>"dhh/app", :absolute_image=>"dhh/app:missing", :service_with_version=>"app-missing", :env_args=>["-e", "REDIS_URL=\"redis://x/y\""], :ssh_options=>{:user=>"root", :auth_methods=>["publickey"]}, :volume_args=>["--volume", "/local/path:/container/path"], :healthcheck=>{"path"=>"/up", "port"=>3000 }}, @config.to_h)
   end
 end

test/fixtures/deploy.erb.yml

@@ -0,0 +1,11 @@
+service: app
+image: dhh/app
+servers:
+  - 1.1.1.1
+  - 1.1.1.2
+env:
+  REDIS_URL: redis://x/y
+registry:
+  server: registry.digitalocean.com
+  username: <%= "my-user" %>
+  password: <%= "my-password" %>

test/fixtures/deploy_for_dest.mars.yml

@@ -0,0 +1,5 @@
+servers:
+  - 1.1.1.3
+  - 1.1.1.4
+env:
+  REDIS_URL: redis://a/b

test/fixtures/deploy_for_dest.world.yml

@@ -0,0 +1,5 @@
+servers:
+  - 1.1.1.1
+  - 1.1.1.2
+env:
+  REDIS_URL: redis://x/y

test/fixtures/deploy_for_dest.yml

@@ -0,0 +1,6 @@
+service: app
+image: dhh/app
+registry:
+  server: registry.digitalocean.com
+  username: <%= "my-user" %>
+  password: <%= "my-password" %>

test/fixtures/deploy_with_accessories.yml

@@ -0,0 +1,29 @@
+service: app
+image: dhh/app
+servers:
+  - 1.1.1.1
+  - 1.1.1.2
+registry:
+  username: user
+  password: pw
+
+accessories:
+  mysql:
+    image: mysql:5.7
+    host: 1.1.1.3
+    port: 3306
+    env:
+      clear:
+        MYSQL_ROOT_HOST: '%'
+      secret:
+        - MYSQL_ROOT_PASSWORD
+    files:
+      - test/fixtures/files/my.cnf:/etc/mysql/my.cnf
+    directories:
+      - data:/var/lib/mysql
+  redis:
+    image: redis:latest
+    host: 1.1.1.4
+    port: 6379
+    directories:
+      - data:/data

test/fixtures/deploy_with_roles.yml

@@ -0,0 +1,15 @@
+service: app
+image: dhh/app
+servers:
+  web:
+    - 1.1.1.1
+    - 1.1.1.2
+  workers:
+    - 1.1.1.3
+    - 1.1.1.4
+env:
+  REDIS_URL: redis://x/y
+registry:
+  server: registry.digitalocean.com
+  username: user
+  password: pw

test/fixtures/files/my.cnf

@@ -0,0 +1 @@
+# MySQL Config

test/fixtures/files/structure.sql.erb

@@ -0,0 +1,2 @@
+<%= "This was dynamically expanded" %>
+<%= ENV["MYSQL_ROOT_HOST"] %>

test/test_helper.rb

@@ -1,8 +1,15 @@
 require "bundler/setup"
 require "active_support/test_case"
 require "active_support/testing/autorun"
+require "debug"
+require "mocha/minitest" # using #stubs that can alter returns
+require "minitest/autorun" # using #stub that take args
+require "sshkit"
+require "mrsk"
 
 ActiveSupport::LogSubscriber.logger = ActiveSupport::Logger.new(STDOUT) if ENV["VERBOSE"]
 
+SSHKit.config.backend = SSHKit::Backend::Printer
+
 class ActiveSupport::TestCase
 end