Host specific env with tags

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.

lib/kamal/cli/app.rb

@@ -37,7 +37,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
         roles.each do |role|
           execute *KAMAL.auditor.record("Started app version #{KAMAL.config.version}"), verbosity: :debug
-          execute *KAMAL.app(role: role).start, raise_on_non_zero_exit: false
+          execute *KAMAL.app(role: role, host: host).start, raise_on_non_zero_exit: false
         end
       end
     end
@@ -51,7 +51,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
         roles.each do |role|
           execute *KAMAL.auditor.record("Stopped app", role: role), verbosity: :debug
-          execute *KAMAL.app(role: role).stop, raise_on_non_zero_exit: false
+          execute *KAMAL.app(role: role, host: host).stop, raise_on_non_zero_exit: false
         end
       end
     end
@@ -64,7 +64,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
       roles = KAMAL.roles_on(host)
 
       roles.each do |role|
-        puts_by_host host, capture_with_info(*KAMAL.app(role: role).info)
+        puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).info)
       end
     end
   end
@@ -80,7 +80,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
       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 #{KAMAL.primary_host}...", :magenta
-        run_locally { exec KAMAL.app(role: KAMAL.primary_role).execute_in_existing_container_over_ssh(cmd, host: KAMAL.primary_host, env: env) }
+        run_locally { exec KAMAL.app(role: KAMAL.primary_role, host: KAMAL.primary_host).execute_in_existing_container_over_ssh(cmd, env: env) }
       end
 
     when options[:interactive]
@@ -88,7 +88,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
       using_version(version_or_latest) do |version|
         say "Launching interactive command with version #{version} via SSH from new container on #{KAMAL.primary_host}...", :magenta
         run_locally do
-          exec KAMAL.app(role: KAMAL.primary_role).execute_in_new_container_over_ssh(cmd, host: KAMAL.primary_host, env: env)
+          exec KAMAL.app(role: KAMAL.primary_role, host: KAMAL.primary_host).execute_in_new_container_over_ssh(cmd, env: env)
         end
       end
 
@@ -102,7 +102,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
           roles.each do |role|
             execute *KAMAL.auditor.record("Executed cmd '#{cmd}' on app version #{version}", role: role), verbosity: :debug
-            puts_by_host host, capture_with_info(*KAMAL.app(role: role).execute_in_existing_container(cmd, env: env))
+            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).execute_in_existing_container(cmd, env: env))
           end
         end
       end
@@ -116,7 +116,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
           roles.each do |role|
             execute *KAMAL.auditor.record("Executed cmd '#{cmd}' on app version #{version}"), verbosity: :debug
-            puts_by_host host, capture_with_info(*KAMAL.app(role: role).execute_in_new_container(cmd, env: env))
+            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).execute_in_new_container(cmd, env: env))
           end
         end
       end
@@ -140,13 +140,14 @@ class Kamal::Cli::App < Kamal::Cli::Base
         roles = KAMAL.roles_on(host)
 
         roles.each do |role|
-          versions = capture_with_info(*KAMAL.app(role: role).list_versions, raise_on_non_zero_exit: false).split("\n")
-          versions -= [ capture_with_info(*KAMAL.app(role: role).current_running_version, raise_on_non_zero_exit: false).strip ]
+          app = KAMAL.app(role: role, host: host)
+          versions = capture_with_info(*app.list_versions, raise_on_non_zero_exit: false).split("\n")
+          versions -= [ capture_with_info(*app.current_running_version, raise_on_non_zero_exit: false).strip ]
 
           versions.each do |version|
             if stop
               puts_by_host host, "Stopping stale container for role #{role} with version #{version}"
-              execute *KAMAL.app(role: role).stop(version: version), raise_on_non_zero_exit: false
+              execute *app.stop(version: version), raise_on_non_zero_exit: false
             else
               puts_by_host host,  "Detected stale container for role #{role} with version #{version} (use `kamal app stale_containers --stop` to stop)"
             end
@@ -180,8 +181,9 @@ class Kamal::Cli::App < Kamal::Cli::Base
         KAMAL.specific_roles ||= [ "web" ]
         role = KAMAL.roles_on(KAMAL.primary_host).first
 
-        info KAMAL.app(role: role).follow_logs(host: KAMAL.primary_host, lines: lines, grep: grep)
-        exec KAMAL.app(role: role).follow_logs(host: KAMAL.primary_host, lines: lines, grep: grep)
+        app = KAMAL.app(role: role, host: host)
+        info app.follow_logs(host: KAMAL.primary_host, lines: lines, grep: grep)
+        exec app.follow_logs(host: KAMAL.primary_host, lines: lines, grep: grep)
       end
     else
       lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
@@ -191,7 +193,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
         roles.each do |role|
           begin
-            puts_by_host host, capture_with_info(*KAMAL.app(role: role).logs(since: since, lines: lines, grep: grep))
+            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).logs(since: since, lines: lines, grep: grep))
           rescue SSHKit::Command::Failed
             puts_by_host host, "Nothing found"
           end
@@ -217,7 +219,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
         roles.each do |role|
           execute *KAMAL.auditor.record("Removed app container with version #{version}", role: role), verbosity: :debug
-          execute *KAMAL.app(role: role).remove_container(version: version)
+          execute *KAMAL.app(role: role, host: host).remove_container(version: version)
         end
       end
     end
@@ -231,7 +233,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
         roles.each do |role|
           execute *KAMAL.auditor.record("Removed all app containers", role: role), verbosity: :debug
-          execute *KAMAL.app(role: role).remove_containers
+          execute *KAMAL.app(role: role, host: host).remove_containers
         end
       end
     end
@@ -251,7 +253,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
   def version
     on(KAMAL.hosts) do |host|
       role = KAMAL.roles_on(host).first
-      puts_by_host host, capture_with_info(*KAMAL.app(role: role).current_running_version).strip
+      puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).current_running_version).strip
     end
   end
 
@@ -274,7 +276,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
       version = nil
       on(host) do
         role = KAMAL.roles_on(host).first
-        version = capture_with_info(*KAMAL.app(role: role).current_running_version).strip
+        version = capture_with_info(*KAMAL.app(role: role, host: host).current_running_version).strip
       end
       version.presence
     end

lib/kamal/cli/app/boot.rb

@@ -22,7 +22,7 @@ class Kamal::Cli::App::Boot
 
   private
     def app
-      @app ||= KAMAL.app(role: role)
+      @app ||= KAMAL.app(role: role, host: host)
     end
 
     def auditor

lib/kamal/cli/app/prepare_assets.rb

@@ -19,6 +19,6 @@ class Kamal::Cli::App::PrepareAssets
 
   private
     def app
-      @app ||= KAMAL.app(role: role)
+      @app ||= KAMAL.app(role: role, host: host)
     end
 end

lib/kamal/cli/env.rb

@@ -8,8 +8,8 @@ class Kamal::Cli::Env < Kamal::Cli::Base
         execute *KAMAL.auditor.record("Pushed env files"), verbosity: :debug
 
         KAMAL.roles_on(host).each do |role|
-          execute *KAMAL.app(role: role).make_env_directory
-          upload! role.env.secrets_io, role.env.secrets_file, mode: 400
+          execute *KAMAL.app(role: role, host: host).make_env_directory
+          upload! role.env(host).secrets_io, role.env(host).secrets_file, mode: 400
         end
       end
 
@@ -35,7 +35,7 @@ class Kamal::Cli::Env < Kamal::Cli::Base
         execute *KAMAL.auditor.record("Deleted env files"), verbosity: :debug
 
         KAMAL.roles_on(host).each do |role|
-          execute *KAMAL.app(role: role).remove_env_file
+          execute *KAMAL.app(role: role, host: host).remove_env_file
         end
       end
 

lib/kamal/cli/main.rb

@@ -246,7 +246,7 @@ class Kamal::Cli::Main < Kamal::Cli::Base
       begin
         on(KAMAL.hosts) do
           KAMAL.roles_on(host).each do |role|
-            container_id = capture_with_info(*KAMAL.app(role: role).container_id_for_version(version))
+            container_id = capture_with_info(*KAMAL.app(role: role, host: host).container_id_for_version(version))
             raise "Container not found" unless container_id.present?
           end
         end

lib/kamal/commander.rb

@@ -65,8 +65,8 @@ class Kamal::Commander
   end
 
 
-  def app(role: nil)
-    Kamal::Commands::App.new(config, role: role)
+  def app(role: nil, host: nil)
+    Kamal::Commands::App.new(config, role: role, host: host)
   end
 
   def accessory(name)

lib/kamal/commands/app.rb

@@ -3,11 +3,12 @@ class Kamal::Commands::App < Kamal::Commands::Base
 
   ACTIVE_DOCKER_STATUSES = [ :running, :restarting ]
 
-  attr_reader :role, :role
+  attr_reader :role, :host
 
-  def initialize(config, role: nil)
+  def initialize(config, role: nil, host: nil)
     super(config)
     @role = role
+    @host = host
   end
 
   def run(hostname: nil)
@@ -18,7 +19,7 @@ class Kamal::Commands::App < Kamal::Commands::Base
       *([ "--hostname", hostname ] if hostname),
       "-e", "KAMAL_CONTAINER_NAME=\"#{container_name}\"",
       "-e", "KAMAL_VERSION=\"#{config.version}\"",
-      *role.env_args,
+      *role.env_args(host),
       *role.health_check_args,
       *role.logging_args,
       *config.volume_args,
@@ -70,11 +71,11 @@ class Kamal::Commands::App < Kamal::Commands::Base
 
 
   def make_env_directory
-    make_directory role.env.secrets_directory
+    make_directory role.env(host).secrets_directory
   end
 
   def remove_env_file
-    [ :rm, "-f", role.env.secrets_file ]
+    [ :rm, "-f", role.env(host).secrets_file ]
   end
 
 

lib/kamal/commands/app/execution.rb

@@ -11,7 +11,7 @@ module Kamal::Commands::App::Execution
     docker :run,
       ("-it" if interactive),
       "--rm",
-      *role&.env_args,
+      *role&.env_args(host),
       *argumentize("--env", env),
       *config.volume_args,
       *role&.option_args,
@@ -19,11 +19,11 @@ module Kamal::Commands::App::Execution
       *command
   end
 
-  def execute_in_existing_container_over_ssh(*command, host:, env:)
+  def execute_in_existing_container_over_ssh(*command,  env:)
     run_over_ssh execute_in_existing_container(*command, interactive: true, env: env), host: host
   end
 
-  def execute_in_new_container_over_ssh(*command, host:, env:)
+  def execute_in_new_container_over_ssh(*command, env:)
     run_over_ssh execute_in_new_container(*command, interactive: true, env: env), host: host
   end
 end

lib/kamal/commands/healthcheck.rb

@@ -8,7 +8,7 @@ class Kamal::Commands::Healthcheck < Kamal::Commands::Base
       "--publish", "#{exposed_port}:#{config.healthcheck["port"]}",
       "--label", "service=#{config.healthcheck_service}",
       "-e", "KAMAL_CONTAINER_NAME=\"#{config.healthcheck_service}\"",
-      *primary.env_args,
+      *primary.env_args(config.primary_host),
       *primary.health_check_args(cord: false),
       *config.volume_args,
       *primary.option_args,

lib/kamal/configuration.rb

@@ -233,6 +233,14 @@ class Kamal::Configuration
     raw_config.env || {}
   end
 
+  def env_tags
+    raw_config.env_tags.collect { |name, config| Kamal::Configuration::Env::Tag.new(name, config: config) }
+  end
+
+  def env_tag(name)
+    env_tags.detect { |t| t.name == name.to_s }
+  end
+
 
   def valid?
     ensure_destination_if_required && ensure_required_keys_present && ensure_valid_kamal_version && ensure_retain_containers_valid && ensure_valid_service_name

lib/kamal/configuration/env/tag.rb

@@ -0,0 +1,12 @@
+class Kamal::Configuration::Env::Tag
+  attr_reader :name, :config
+
+  def initialize(name, config:)
+    @name = name
+    @config = config
+  end
+
+  def env
+    Kamal::Configuration::Env.from_config(config: config)
+  end
+end

lib/kamal/configuration/role.rb

@@ -7,6 +7,7 @@ class Kamal::Configuration::Role
 
   def initialize(name, config:)
     @name, @config = name.inquiry, config
+    @tagged_hosts ||= extract_tagged_hosts_from_config
   end
 
   def primary_host
@@ -14,7 +15,11 @@ class Kamal::Configuration::Role
   end
 
   def hosts
-    @hosts ||= extract_hosts_from_config
+    tagged_hosts.keys
+  end
+
+  def env_tags(host)
+    tagged_hosts.fetch(host).collect { |tag| config.env_tag(tag) }
   end
 
   def cmd
@@ -50,12 +55,13 @@ class Kamal::Configuration::Role
   end
 
 
-  def env
-    @env ||= base_env.merge(specialized_env)
+  def env(host)
+    @envs ||= {}
+    @envs[host] ||= [ base_env, specialized_env, *env_tags(host).map(&:env) ].reduce(:merge)
   end
 
-  def env_args
-    env.args
+  def env_args(host)
+    env(host).args
   end
 
   def asset_volume_args
@@ -164,7 +170,24 @@ class Kamal::Configuration::Role
   end
 
   private
-    attr_accessor :config
+    attr_accessor :config, :tagged_hosts
+
+    def extract_tagged_hosts_from_config
+      {}.tap do |tagged_hosts|
+        extract_hosts_from_config.map do |host_config|
+          if host_config.is_a?(Hash)
+            raise ArgumentError, "Multiple hosts found: #{host_config.inspect}" unless host_config.size == 1
+
+            host, tags = host_config.first
+            tagged_hosts[host] = Array(tags)
+          elsif host_config.is_a?(String) || host_config.is_a?(Symbol)
+            tagged_hosts[host_config] = []
+          else
+            raise ArgumentError, "Invalid host config: #{host_config.inspect}"
+          end
+        end
+      end
+    end
 
     def extract_hosts_from_config
       if config.servers.is_a?(Array)

test/cli/app_test.rb

@@ -92,6 +92,32 @@ class CliAppTest < CliTestCase
     end
   end
 
+  test "boot with host tags" do
+    Object.any_instance.stubs(:sleep)
+
+    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info)
+    .with(:docker, :container, :ls, "--all", "--filter", "name=^app-web-latest$", "--quiet", raise_on_non_zero_exit: false)
+    .returns("12345678") # running version
+
+    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info)
+      .with(:docker, :container, :ls, "--all", "--filter", "name=^app-web-latest$", "--quiet", "|", :xargs, :docker, :inspect, "--format", "'{{if .State.Health}}{{.State.Health.Status}}{{else}}{{.State.Status}}{{end}}'")
+      .returns("running") # health check
+
+    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info)
+      .with(:sh, "-c", "'docker ps --latest --format '\\''{{.Names}}'\\'' --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting --filter ancestor=$(docker image ls --filter reference=dhh/app:latest --format '\\''{{.ID}}'\\'') ; docker ps --latest --format '\\''{{.Names}}'\\'' --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting'", "|", :head, "-1", "|", "while read line; do echo ${line#app-web-}; done", raise_on_non_zero_exit: false)
+      .returns("123") # old version
+
+    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info)
+      .with(:docker, :inspect, "-f '{{ range .Mounts }}{{printf \"%s %s\\n\" .Source .Destination}}{{ end }}'", "app-web-123", "|", :awk, "'$2 == \"/tmp/kamal-cord\" {print $1}'", raise_on_non_zero_exit: false)
+      .returns("") # old version
+
+    run_command("boot", config: :with_env_tags).tap do |output|
+      assert_match "docker tag dhh/app:latest dhh/app:latest", output
+      assert_match %r{docker run --detach --restart unless-stopped --name app-web-latest --hostname 1.1.1.1-[0-9a-f]{12} -e KAMAL_CONTAINER_NAME="app-web-latest" -e KAMAL_VERSION="latest" --env-file .kamal/env/roles/app-web.env --env TEST="root" --env EXPERIMENT="disabled" --env SITE="site1"}, output
+      assert_match "docker container ls --all --filter name=^app-web-123$ --quiet | xargs docker stop", output
+    end
+  end
+
   test "start" do
     run_command("start").tap do |output|
       assert_match "docker start app-web-999", output

test/commands/app_test.rb

@@ -60,7 +60,7 @@ class CommandsAppTest < ActiveSupport::TestCase
     @config[:servers] = { "web" => [ "1.1.1.1" ], "jobs" => { "hosts" => [ "1.1.1.2" ], "cmd" => "bin/jobs", "options" => { "mount" => "somewhere", "cap-add" => true } } }
     assert_equal \
       "docker run --detach --restart unless-stopped --name app-jobs-999 -e KAMAL_CONTAINER_NAME=\"app-jobs-999\" -e KAMAL_VERSION=\"999\" --env-file .kamal/env/roles/app-jobs.env --log-opt max-size=\"10m\" --label service=\"app\" --label role=\"jobs\" --label destination --mount \"somewhere\" --cap-add dhh/app:999 bin/jobs",
-      new_command(role: "jobs").run.join(" ")
+      new_command(role: "jobs", host: "1.1.1.2").run.join(" ")
   end
 
   test "run with logging config" do
@@ -80,6 +80,15 @@ class CommandsAppTest < ActiveSupport::TestCase
       new_command.run.join(" ")
   end
 
+  test "run with tags" do
+    @config[:servers] = [ { "1.1.1.1" => "tag1" } ]
+    @config[:env_tags] = { "tag1" => { "ENV1" => "value1" } }
+
+    assert_equal \
+      "docker run --detach --restart unless-stopped --name app-web-999 -e KAMAL_CONTAINER_NAME=\"app-web-999\" -e KAMAL_VERSION=\"999\" --env-file .kamal/env/roles/app-web.env --env ENV1=\"value1\" --health-cmd \"(curl -f http://localhost:3000/up || exit 1) && (stat /tmp/kamal-cord/cord > /dev/null || exit 1)\" --health-interval \"1s\" --volume $(pwd)/.kamal/cords/app-web-12345678901234567890123456789012:/tmp/kamal-cord --log-opt max-size=\"10m\" --label service=\"app\" --label role=\"web\" --label destination --label traefik.http.services.app-web.loadbalancer.server.scheme=\"http\" --label traefik.http.routers.app-web.rule=\"PathPrefix(\\`/\\`)\" --label traefik.http.routers.app-web.priority=\"2\" --label traefik.http.middlewares.app-web-retry.retry.attempts=\"5\" --label traefik.http.middlewares.app-web-retry.retry.initialinterval=\"500ms\" --label traefik.http.routers.app-web.middlewares=\"app-web-retry@docker\" dhh/app:999",
+      new_command.run.join(" ")
+  end
+
   test "start" do
     assert_equal \
       "docker start app-web-999",
@@ -183,6 +192,15 @@ class CommandsAppTest < ActiveSupport::TestCase
       new_command.execute_in_new_container("bin/rails", "db:setup", env: { "foo" => "bar" }).join(" ")
   end
 
+  test "execute in new container with tags" do
+    @config[:servers] = [ { "1.1.1.1" => "tag1" } ]
+    @config[:env_tags] = { "tag1" => { "ENV1" => "value1" } }
+
+    assert_equal \
+      "docker run --rm --env-file .kamal/env/roles/app-web.env --env ENV1=\"value1\" dhh/app:999 bin/rails db:setup",
+      new_command.execute_in_new_container("bin/rails", "db:setup", env: {}).join(" ")
+  end
+
   test "execute in new container with custom options" do
     @config[:servers] = { "web" => { "hosts" => [ "1.1.1.1" ], "options" => { "mount" => "somewhere", "cap-add" => true } } }
     assert_equal \
@@ -204,18 +222,26 @@ class CommandsAppTest < ActiveSupport::TestCase
 
   test "execute in new container over ssh" do
     assert_match %r{docker run -it --rm --env-file .kamal/env/roles/app-web.env dhh/app:999 bin/rails c},
-      new_command.execute_in_new_container_over_ssh("bin/rails", "c", host: "app-1", env: {})
+      new_command.execute_in_new_container_over_ssh("bin/rails", "c", env: {})
+  end
+
+  test "execute in new container over ssh with tags" do
+    @config[:servers] = [ { "1.1.1.1" => "tag1" } ]
+    @config[:env_tags] = { "tag1" => { "ENV1" => "value1" } }
+
+    assert_equal "ssh -t root@1.1.1.1 -p 22 'docker run -it --rm --env-file .kamal/env/roles/app-web.env --env ENV1=\"value1\" dhh/app:999 bin/rails c'",
+      new_command.execute_in_new_container_over_ssh("bin/rails", "c", env: {})
   end
 
   test "execute in new container with custom options over ssh" do
     @config[:servers] = { "web" => { "hosts" => [ "1.1.1.1" ], "options" => { "mount" => "somewhere", "cap-add" => true } } }
     assert_match %r{docker run -it --rm --env-file .kamal/env/roles/app-web.env --mount \"somewhere\" --cap-add dhh/app:999 bin/rails c},
-      new_command.execute_in_new_container_over_ssh("bin/rails", "c", host: "app-1", env: {})
+      new_command.execute_in_new_container_over_ssh("bin/rails", "c", env: {})
   end
 
   test "execute in existing container over ssh" do
     assert_match %r{docker exec -it app-web-999 bin/rails c},
-      new_command.execute_in_existing_container_over_ssh("bin/rails", "c", host: "app-1", env: {})
+      new_command.execute_in_existing_container_over_ssh("bin/rails", "c", env: {})
   end
 
   test "run over ssh" do
@@ -418,8 +444,8 @@ class CommandsAppTest < ActiveSupport::TestCase
   end
 
   private
-    def new_command(role: "web", **additional_config)
+    def new_command(role: "web", host: "1.1.1.1", **additional_config)
       config = Kamal::Configuration.new(@config.merge(additional_config), destination: @destination, version: "999")
-      Kamal::Commands::App.new(config, role: config.role(role))
+      Kamal::Commands::App.new(config, role: config.role(role), host: host)
     end
 end

test/commands/healthcheck_test.rb

@@ -46,6 +46,15 @@ class CommandsHealthcheckTest < ActiveSupport::TestCase
       new_command.run.join(" ")
   end
 
+  test "run with tags" do
+    @config[:servers] = [ { "1.1.1.1" => "tag1" } ]
+    @config[:env_tags] = { "tag1" => { "ENV1" => "value1" } }
+
+    assert_equal \
+      "docker run --detach --name healthcheck-app-123 --publish 3999:3000 --label service=healthcheck-app -e KAMAL_CONTAINER_NAME=\"healthcheck-app\" --env-file .kamal/env/roles/app-web.env --env ENV1=\"value1\" --health-cmd \"curl -f http://localhost:3000/up || exit 1\" --health-interval \"1s\" dhh/app:123",
+      new_command.run.join(" ")
+  end
+
   test "status" do
     assert_equal \
       "docker container ls --all --filter name=^healthcheck-app-123$ --quiet | xargs docker inspect --format '{{if .State.Health}}{{.State.Health.Status}}{{else}}{{.State.Status}}{{end}}'",

test/configuration/env/tags_test.rb

@@ -0,0 +1,102 @@
+require "test_helper"
+
+class ConfigurationEnvTagsTest < ActiveSupport::TestCase
+  setup do
+    @deploy = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
+      servers: [ { "1.1.1.1" => "odd" }, { "1.1.1.2" => "even" }, { "1.1.1.3" => [ "odd", "three" ] } ],
+      env: { "REDIS_URL" => "redis://x/y", "THREE" => "false" },
+      env_tags: {
+        "odd" => { "TYPE" => "odd" },
+        "even" => { "TYPE" => "even" },
+        "three" => { "THREE" => "true" }
+      }
+    }
+
+    @config = Kamal::Configuration.new(@deploy)
+
+    @deploy_with_roles = @deploy.dup.merge({
+      servers: {
+        "web" => [ { "1.1.1.1" => "odd" }, "1.1.1.2" ],
+        "workers" => {
+          "hosts" => [ { "1.1.1.3" => [ "odd", "oddjob" ] }, "1.1.1.4" ],
+          "cmd" => "bin/jobs",
+          "env" => {
+            "REDIS_URL" => "redis://a/b",
+            "WEB_CONCURRENCY" => 4
+          }
+        }
+      },
+      env_tags: {
+        "odd" => { "TYPE" => "odd" },
+        "oddjob" => { "TYPE" => "oddjob" }
+      }
+    })
+
+    @config_with_roles = Kamal::Configuration.new(@deploy_with_roles)
+  end
+
+  test "tags" do
+    assert_equal 3, @config.env_tags.size
+    assert_equal %w[ odd even three ], @config.env_tags.map(&:name)
+    assert_equal({ "TYPE" => "odd" }, @config.env_tag("odd").env.clear)
+    assert_equal({ "TYPE" => "even" }, @config.env_tag("even").env.clear)
+    assert_equal({ "THREE" => "true" }, @config.env_tag("three").env.clear)
+  end
+
+  test "tags with roles" do
+    assert_equal 2, @config_with_roles.env_tags.size
+    assert_equal %w[ odd oddjob ], @config_with_roles.env_tags.map(&:name)
+    assert_equal({ "TYPE" => "odd" }, @config_with_roles.env_tag("odd").env.clear)
+    assert_equal({ "TYPE" => "oddjob" }, @config_with_roles.env_tag("oddjob").env.clear)
+  end
+
+  test "tag overrides env" do
+    assert_equal "false", @config.role("web").env("1.1.1.1").clear["THREE"]
+    assert_equal "true", @config.role("web").env("1.1.1.3").clear["THREE"]
+  end
+
+  test "later tag wins" do
+    deploy = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
+      servers: [ { "1.1.1.1" => [ "first", "second" ] } ],
+      env_tags: {
+        "first" => { "TYPE" => "first" },
+        "second" => { "TYPE" => "second" }
+      }
+    }
+
+    config = Kamal::Configuration.new(deploy)
+    assert_equal "second", config.role("web").env("1.1.1.1").clear["TYPE"]
+  end
+
+  test "tag secret env" do
+    ENV["PASSWORD"] = "hello"
+
+    deploy = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
+      servers: [ { "1.1.1.1" => "secrets" } ],
+      env_tags: {
+        "secrets" => { "secret" => [ "PASSWORD" ] }
+      }
+    }
+
+    config = Kamal::Configuration.new(deploy)
+    assert_equal "hello", config.role("web").env("1.1.1.1").secrets["PASSWORD"]
+  ensure
+    ENV.delete "PASSWORD"
+  end
+
+  test "tag clear env" do
+    deploy = {
+      service: "app", image: "dhh/app", registry: { "username" => "dhh", "password" => "secret" },
+      servers: [ { "1.1.1.1" => "clearly" } ],
+      env_tags: {
+        "clearly" => { "clear" => { "FOO" => "bar" } }
+      }
+    }
+
+    config = Kamal::Configuration.new(deploy)
+    assert_equal "bar", config.role("web").env("1.1.1.1").clear["FOO"]
+  end
+end

test/configuration/role_test.rb

@@ -70,10 +70,10 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
   end
 
   test "env overwritten by role" do
-    assert_equal "redis://a/b", @config_with_roles.role(:workers).env.clear["REDIS_URL"]
+    assert_equal "redis://a/b", @config_with_roles.role(:workers).env("1.1.1.3").clear["REDIS_URL"]
 
-    assert_equal "\n", @config_with_roles.role(:workers).env.secrets_io.string
-    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args
+    assert_equal "\n", @config_with_roles.role(:workers).env("1.1.1.3").secrets_io.string
+    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args("1.1.1.3")
   end
 
   test "container name" do
@@ -86,7 +86,7 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
   end
 
   test "env args" do
-    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args
+    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args("1.1.1.3")
   end
 
   test "env secret overwritten by role" do
@@ -117,8 +117,8 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
       DB_PASSWORD=secret&\"123
     ENV
 
-    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env.secrets_io.string
-    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args
+    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env("1.1.1.3").secrets_io.string
+    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args("1.1.1.3")
   ensure
     ENV["REDIS_PASSWORD"] = nil
     ENV["DB_PASSWORD"] = nil
@@ -141,8 +141,8 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
       DB_PASSWORD=secret123
     ENV
 
-    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env.secrets_io.string
-    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args
+    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env("1.1.1.3").secrets_io.string
+    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args("1.1.1.3")
   ensure
     ENV["DB_PASSWORD"] = nil
   end
@@ -163,8 +163,8 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
       REDIS_PASSWORD=secret456
     ENV
 
-    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env.secrets_io.string
-    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args
+    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env("1.1.1.3").secrets_io.string
+    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://a/b\"", "--env", "WEB_CONCURRENCY=\"4\"" ], @config_with_roles.role(:workers).env_args("1.1.1.3")
   ensure
     ENV["REDIS_PASSWORD"] = nil
   end
@@ -191,14 +191,14 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
       REDIS_PASSWORD=secret456
     ENV
 
-    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env.secrets_io.string
-    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://c/d\"" ], @config_with_roles.role(:workers).env_args
+    assert_equal expected_secrets_file, @config_with_roles.role(:workers).env("1.1.1.3").secrets_io.string
+    assert_equal [ "--env-file", ".kamal/env/roles/app-workers.env", "--env", "REDIS_URL=\"redis://c/d\"" ], @config_with_roles.role(:workers).env_args("1.1.1.3")
   ensure
     ENV["REDIS_PASSWORD"] = nil
   end
 
   test "env secrets_file" do
-    assert_equal ".kamal/env/roles/app-workers.env", @config_with_roles.role(:workers).env.secrets_file
+    assert_equal ".kamal/env/roles/app-workers.env", @config_with_roles.role(:workers).env("1.1.1.3").secrets_file
   end
 
   test "uses cord" do

test/fixtures/deploy_with_env_tags.yml

@@ -0,0 +1,29 @@
+service: app
+image: dhh/app
+servers:
+  web:
+    - 1.1.1.1: site1
+    - 1.1.1.2: [ site1 experimental ]
+    - 1.2.1.1: site2
+    - 1.2.1.2: site2
+  workers:
+    - 1.1.1.3: site1
+    - 1.1.1.4: site1
+    - 1.2.1.3: site2
+    - 1.2.1.4: [ site2 experimental ]
+env:
+  clear:
+    TEST: "root"
+    EXPERIMENT: "disabled"
+env_tags:
+  site1:
+    SITE: site1
+  site2:
+    SITE: site2
+  experimental:
+    env:
+      EXPERIMENT: "enabled"
+
+registry:
+  username: user
+  password: pw

test/integration/docker/deployer/app/.env.erb

@@ -1 +1,2 @@
 SECRET_TOKEN='1234 with "中文"'
+SECRET_TAG='TAGME'

test/integration/docker/deployer/app/config/deploy.yml

@@ -2,13 +2,20 @@ service: app
 image: app
 servers:
   - vm1
-  - vm2
+  - vm2: [ tag1, tag2 ]
 env:
   clear:
     CLEAR_TOKEN: 4321
+    CLEAR_TAG: ""
     HOST_TOKEN: "${HOST_TOKEN}"
   secret:
     - SECRET_TOKEN
+env_tags:
+  tag1:
+    CLEAR_TAG: tagged
+  tag2:
+    secret:
+      - SECRET_TAG
 asset_path: /usr/share/nginx/html/versions
 
 registry:

test/integration/main_test.rb

@@ -3,8 +3,7 @@ require_relative "integration_test"
 class MainTest < IntegrationTest
   test "envify, deploy, redeploy, rollback, details and audit" do
     kamal :envify
-    assert_local_env_file "SECRET_TOKEN='1234 with \"中文\"'"
-    assert_remote_env_file "SECRET_TOKEN=1234 with \"中文\""
+    assert_env_files
     remove_local_env_file
 
     first_version = latest_app_version
@@ -14,9 +13,7 @@ class MainTest < IntegrationTest
     kamal :deploy
     assert_app_is_up version: first_version
     assert_hooks_ran "pre-connect", "pre-build", "pre-deploy", "post-deploy"
-    assert_env :CLEAR_TOKEN, "4321", version: first_version
-    assert_env :HOST_TOKEN, "abcd", version: first_version
-    assert_env :SECRET_TOKEN, "1234 with \"中文\"", version: first_version
+    assert_envs version: first_version
 
     second_version = update_app_rev
 
@@ -97,16 +94,38 @@ class MainTest < IntegrationTest
       assert_equal contents, deployer_exec("cat .env", capture: true)
     end
 
-    def assert_env(key, value, version:)
-      assert_equal "#{key}=#{value}", docker_compose("exec vm1 docker exec app-web-#{version} env | grep #{key}", capture: true)
+    def assert_envs(version:)
+      assert_env :CLEAR_TOKEN, "4321", version: version, vm: :vm1
+      assert_env :HOST_TOKEN, "abcd", version: version, vm: :vm1
+      assert_env :SECRET_TOKEN, "1234 with \"中文\"", version: version, vm: :vm1
+      assert_no_env :CLEAR_TAG, version: version, vm: :vm1
+      assert_no_env :SECRET_TAG, version: version, vm: :vm11
+      assert_env :CLEAR_TAG, "tagged", version: version, vm: :vm2
+      assert_env :SECRET_TAG, "TAGME", version: version, vm: :vm2
+    end
+
+    def assert_env(key, value, vm:, version:)
+      assert_equal "#{key}=#{value}", docker_compose("exec #{vm} docker exec app-web-#{version} env | grep #{key}", capture: true)
+    end
+
+    def assert_no_env(key, vm:, version:)
+      assert_raises(RuntimeError, /exit 1/) do
+        docker_compose("exec #{vm} docker exec app-web-#{version} env | grep #{key}", capture: true)
+      end
+    end
+
+    def assert_env_files
+      assert_local_env_file "SECRET_TOKEN='1234 with \"中文\"'\nSECRET_TAG='TAGME'"
+      assert_remote_env_file "SECRET_TOKEN=1234 with \"中文\"", vm: :vm1
+      assert_remote_env_file "SECRET_TOKEN=1234 with \"中文\"\nSECRET_TAG=TAGME", vm: :vm2
     end
 
     def remove_local_env_file
       deployer_exec("rm .env")
     end
 
-    def assert_remote_env_file(contents)
-      assert_equal contents, docker_compose("exec vm1 cat /root/.kamal/env/roles/app-web.env", capture: true)
+    def assert_remote_env_file(contents, vm:)
+      assert_equal contents, docker_compose("exec #{vm} cat /root/.kamal/env/roles/app-web.env", capture: true)
     end
 
     def assert_no_remote_env_file