Add two new hooks pre-app-boot and post-app-boot. They are analagous
to the pre/post proxy reboot hooks.
If the boot strategy deploys in groups, then the hooks are called once
per group of hosts and `KAMAL_HOSTS` contains a comma delimited list of
the hosts in that group.
If all hosts are deployed to at once, then they are called once with
`KAMAL_HOSTS` containing all the hosts.
It is possible to have pauses between groups of hosts in the boot config,
where this is the case the pause happens after the post-app-boot hook is
called.
We only loaded the configuration once, which meant that aliases always
used the initial configuration file and destination.
We don't want to load the configuration in subcommands as it is not
passed all the options we need. But just checking if we are in a
subcommand is enough - the alias reloads and the subcommand does not.
One thing to note is that anything passed on the command line overrides
what is in the alias, so if an alias says
`other_config: config -c config/deploy2.yml` and you run
`kamal other_config -c config/deploy.yml`, it won't switch.
By default only the primary role runs the proxy. To disable the proxy
for that role, you can set `proxy: false` under it.
For other roles they default to not running the proxy, but you can
enable it by setting `proxy: true` for the role, or alternatively
setting a proxy configuration.
The proxy configuration will be merged into the root proxy configuration.
Remove `stop_wait_time` and `readiness_timeout` from the root config
and remove `deploy_timeout` and `drain_timeout` from the proxy config.
Instead we'll just have `deploy_timeout` and `drain_timeout` in the
root config.
For roles that run the proxy, they are passed to the kamal-proxy deploy
command. Once that returns we can assume the container is ready to
shut down.
For other roles, we'll use the `deploy_timeout` when polling the
container to see if it is ready and the `drain_timeout` when stopping
the container.
Adds:
- `kamal upgrade` to upgrade all app hosts and accessory hosts
- `kamal proxy upgrade` to upgrade the proxy on all hosts
- `kamal accessory upgrade [name]` to upgrade accessories on all hosts
Upgrade takes rolling and confirmed options and calls `proxy upgrade`
and `accessory upgrade` in turn.
To just upgrade a single host add -h [host] to the command. But the
upgrade should run on all hosts, not just those running the proxy.
Calling upgrade on a host that has already been upgraded should work ok.
Upgrading hosts causes downtime but you can avoid if you run multiple
hosts by:
1. Implementing the pre-proxy-reboot and post-proxy-reboot hooks to
remove the host from external load balancers
2. Running the upgrade with the --rolling option
**kamal proxy upgrade**
1. Creates a `kamal` network if required
2. Stops and removes the old proxy (whether Traefik or kamal-proxy)
3. Starts a kamal-proxy container in the `kamal` network
4. Reboots the app containers in the `kamal` network
**kamal accessory upgrade [name]**
1. Creates a `kamal` network if required
2. Reboots the accessory containers in the `kamal` network
A matching `downgrade` command will be added to Kamal 1.9.
The proxy can be enabled via the config:
```
proxy:
enabled: true
hosts:
- 10.0.0.1
- 10.0.0.2
```
This will enable the proxy and cause it to be run on the hosts listed
under `hosts`, after running `kamal proxy reboot`.
Enabling the proxy disables `kamal traefik` commands and replaces them
with `kamal proxy` ones. However only the marked hosts will run the
kamal-proxy container, the rest will run Traefik as before.
1. Add driver as an option, defaulting to `docker-container`. For a
"native" build you can set it to `docker`
2. Set arch as a array of architectures to build for, defaulting to
`[ "amd64", "arm64" ]` unless you are using the docker driver in
which case we default to not setting a platform
3. Remote is now just a connection string for the remote builder
4. If remote is set, we only use it for non-local arches, if we are
only building for the local arch, we'll ignore it.
Examples:
On arm64, build for arm64 locally, amd64 remotely or
On amd64, build for amd64 locally, arm64 remotely:
```yaml
builder:
remote: ssh://docker@docker-builder
```
On arm64, build amd64 on remote,
On amd64 build locally:
```yaml
builder:
arch:
- amd64
remote:
host: ssh://docker@docker-builder
```
Build amd64 on local:
```yaml
builder:
arch:
- amd64
```
Use docker driver, building for local arch:
```yaml
builder:
driver: docker
```
If you can have an alias like:
```
aliases:
rails: app exec -p rails
```
Then `kamal rails db:migrate:status` will execute
`kamal app exec -p rails db:migrate:status`.
So this works, we'll allow multiple arguments `app exec` and
`server exec` to accept multiple arguments.
The arguments are combined by simply joining them with a space. This
means that these are equivalent:
```
kamal app exec -p rails db:migrate:status
kamal app exec -p "rails db:migrate:status"
```
If you want to pass an argument with spaces, you'll need to quote it:
```
kamal app exec -p "git commit -am \"My comment\""
kamal app exec -p git commit -am "\"My comment\""
```
Aliases are defined in the configuration file under the `aliases` key.
The configuration is a map of alias name to command. When we run the
command the we just do a literal replacement of the alias with the
string.
So if we have:
```yaml
aliases:
console: app exec -r console -i --reuse "rails console"
```
Then running `kamal console -r workers` will run the command
```sh
$ kamal app exec -r console -i --reuse "rails console" -r workers
```
Because of the order Thor parses the arguments, this allows us to
override the role from the alias command.
There might be cases where we need to munge the command a bit more but
that would involve getting into Thor command parsing internals,
which are complicated and possibly subject to change.
There's a chance that your aliases could conflict with future built-in
commands, but there's not likely to be many of those and if it happens
you'll get a validation error when you upgrade.
Thanks to @dhnaranjo for the idea!
Allow blocks prefixed with `x-` in the configuration as a place to
declare reusable blocks with YAML anchors and aliases.
Borrowed from the Docker Compose configuration file format -
https://github.com/compose-spec/compose-spec/blob/main/spec.md#extension
Thanks to @ruyrocha for the suggestion.
Validate the Kamal configuration giving useful warning on errors.
Each section of the configuration has its own config class and a YAML
file containing documented example configuration.
You can run `kamal docs` to see the example configuration, and
`kamal docs <section>` to see the example configuration for a specific
section.
The validation matches the configuration to the example configuration
checking that there are no unknown keys and that the values are of
matching types.
Where there is more complex validation - e.g for envs and servers, we
have custom validators that implement those rules.
Additonally the configuration examples are used to generate the
configuration documentation in the kamal-site repo.
You generate them by running:
```
bundle exec bin/docs <kamal-site-checkout>
```
To speed up deployments, we'll remove the healthcheck step.
This adds some risk to deployments for non-web roles - if they don't
have a Docker healthcheck configured then the only check we do is if
the container is running.
If there is a bad image we might see the container running before it
exits and deploy it. Previously the healthcheck step would have avoided
this by ensuring a web container could boot and serve traffic first.
To mitigate this, we'll add a deployment barrier. Until one of the
primary role containers passes its healthcheck, we'll keep the barrier
up and avoid stopping the containers on the non-primary roles.
It the primary role container fails its healthcheck, we'll close the
barrier and shut down the new containers on the waiting roles.
We also have a new integration test to check we correctly handle a
a broken image. This highlighted that SSHKit's default runner will
stop at the first error it encounters. We'll now have a custom runner
that waits for all threads to finish allowing them to clean up.
Docker does not respect the .dockerignore file when building from a tar.
Instead by default we'll make a local clone into a tmp directory and
build from there. Subsequent builds will reset the clone to match the
checkout.
Compared to building directly in the repo, we'll have reproducible
builds.
Compared to using a git archive:
1. .dockerignore is respected
2. We'll have faster builds - docker can be smarter about caching the
build context on subsequent builds from a directory
To build from the repo directly, set the build context to "." in the
config.
If there are uncommitted changes, we'll warn about them either being
included or ignored depending on whether we build from the clone.
Allow hosts to be tagged so we can have host specific env variables.
We might want host specific env variables for things like datacenter
specific tags or testing GC settings on a specific host.
Right now you either need to set up a separate role, or have the app
be host aware.
Now you can define tag env variables and assign those to hosts.
For example:
```
servers:
- 1.1.1.1
- 1.1.1.2: tag1
- 1.1.1.2: tag2
- 1.1.1.3: [ tag1, tag2 ]
env_tags:
tag1:
ENV1: value1
tag2:
ENV2: value2
```
The tag env supports the full env format, allowing you to set secret and
clear values.
When ssh options are set, they overwrite username and password passed as ssh builder uri. Passing part of uri for ssh-kit is fine, as it then properly extracts username and password and forwards it as host.ssh_options (in which case it's no longer empty)
If you always want to use a destination, and have a base deploy.yml file
that doesn't specify any hosts, then if you forget to specific the
destination you will get a cryptic error.
Add a "require_destination" setting you can use to avoid this.
During deployments both the old and new containers will be active for a
small period of time. There also may be lagging requests for older CSS
and JS after the deployment.
This can lead to 404s if a request for old assets hits a new container
or visa-versa.
This PR makes sure that both sets of assets are available throughout the
deployment from before the new version of the app is booted.
This can be configured by setting the asset path:
```yaml
asset_path: "/rails/public/assets"
```
The process is:
1. We extract the assets out of the container, with docker run, docker
cp, docker stop. Docker run sets the container command to "sleep" so
this needs to be available in the container.
2. We create an asset volume directory on the host for the new version
of the app on the host and copy the assets in there.
3. If there is a previous deployment we also copy the new assets into
its asset volume and copy the older assets into the new asset volume.
4. We start the new container mapping the asset volume over the top of
the container's asset path.
This means the both the old and new versions have replaced the asset
path with a volume containing both sets of assets and should be able
to serve any request during the deployment. The older assets will
continue to be available until the next deployment.
Rename `with_lock` to more generic `mutating` and move the env_args
check to that point. This allows read-only actions to be run without
requiring secrets.
These replace the custom audit_broadcast_cmd code. An additional env
variable MRSK_RUNTIME is passed to them.
The audit broadcast after booting an accessory has been removed.
Audit details
* Audit logs and broadcasts accept `details` whose values are included as log tags and MRSK_* env vars passed to the broadcast command
* Commands may return execution options to the CLI in their args list
* Introduce `mrsk broadcast` helper for sending audit broadcasts
* Report UTC time, not local time, in audit logs. Standardize on ISO 8601 format