Rename roles

Allow roles to be renamed without having to manually stop the old
containers.

If you have config like:

```
servers:
  jobs:
    hosts:
      - vm3
```

And you want to rename `jobs` to `workers`, you can do:

```
servers:
  workers:
    previously:
      - jobs
    hosts:
      - vm3
```

And the deployment will take care of stopping the old "jobs" containers.

Once deployed you can remove the `previously` key.

test/configuration/role_test.rb

@@ -53,7 +53,8 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
   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"]
+    config_with_roles = Kamal::Configuration.new(@deploy_with_roles)
+    assert_equal "70", config_with_roles.role(:workers).labels["my.custom.label"]
   end
 
   test "overwriting default traefik label" do
@@ -109,6 +110,8 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
       ]
     }
 
+    config_with_roles = Kamal::Configuration.new(@deploy_with_roles)
+
     ENV["REDIS_PASSWORD"] = "secret456"
     ENV["DB_PASSWORD"] = "secret&\"123"
 
@@ -117,8 +120,8 @@ 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.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
   ensure
     ENV["REDIS_PASSWORD"] = nil
     ENV["DB_PASSWORD"] = nil
@@ -135,14 +138,16 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
       ]
     }
 
+    config_with_roles = Kamal::Configuration.new(@deploy_with_roles)
+
     ENV["DB_PASSWORD"] = "secret123"
 
     expected_secrets_file = <<~ENV
       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.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
   ensure
     ENV["DB_PASSWORD"] = nil
   end
@@ -185,14 +190,16 @@ class ConfigurationRoleTest < ActiveSupport::TestCase
       }
     }
 
+    config_with_roles = Kamal::Configuration.new(@deploy_with_roles)
+
     ENV["REDIS_PASSWORD"] = "secret456"
 
     expected_secrets_file = <<~ENV
       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.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
   ensure
     ENV["REDIS_PASSWORD"] = nil
   end

test/integration/docker/deployer/app_with_roles/config/deploy_renamed_roles.yml

@@ -0,0 +1,42 @@
+service: app
+image: app
+primary_role: app
+servers:
+  app:
+    previously:
+      - web
+    hosts:
+      - vm1
+      - vm2
+  jobs:
+    previously:
+      - workers
+    hosts:
+      - vm3
+    cmd: sleep infinity
+
+asset_path: /usr/share/nginx/html/versions
+
+registry:
+  server: registry:4443
+  username: root
+  password: root
+builder:
+  multiarch: false
+  args:
+    COMMIT_SHA: <%= `git rev-parse HEAD` %>
+healthcheck:
+  cmd: wget -qO- http://localhost > /dev/null || exit 1
+traefik:
+  args:
+    accesslog: true
+    accesslog.format: json
+  image: registry:4443/traefik:v2.10
+accessories:
+  busybox:
+    service: custom-busybox
+    image: registry:4443/busybox:1.36.0
+    cmd: sh -c 'echo "Starting busybox..."; trap exit term; while true; do sleep 1; done'
+    roles:
+      - app
+stop_wait_time: 1

test/integration/docker/deployer/rename_roles.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+cd $1 && cp -f config/deploy_renamed_roles.yml config/deploy.yml && git commit -am 'Rename roles'

test/integration/integration_test.rb

@@ -131,4 +131,16 @@ class IntegrationTest < ActiveSupport::TestCase
         puts "Tried to get the response code again and got #{app_response.code}"
       end
     end
+
+    def assert_container_running(host:, name:)
+      assert container_running?(host: host, name: name)
+    end
+
+    def assert_container_not_running(host:, name:)
+      assert_not container_running?(host: host, name: name)
+    end
+
+    def container_running?(host:, name:)
+      docker_compose("exec #{host} docker ps --filter=name=#{name} | tail -n+2", capture: true).strip.present?
+    end
 end

test/integration/main_test.rb

@@ -92,6 +92,33 @@ class MainTest < IntegrationTest
     assert_no_images_or_containers
   end
 
+  test "rename roles" do
+    @app = "app_with_roles"
+
+    kamal :envify
+    kamal :deploy
+
+    first_version = latest_app_version
+
+    assert_container_running host: :vm1, name: "app-web-#{first_version}"
+    assert_container_running host: :vm2, name: "app-web-#{first_version}"
+    assert_container_running host: :vm3, name: "app-workers-#{first_version}"
+
+    rename_roles
+
+    kamal :envify
+    kamal :deploy
+
+    second_version = latest_app_version
+
+    assert_container_running host: :vm1, name: "app-app-#{second_version}"
+    assert_container_running host: :vm2, name: "app-app-#{second_version}"
+    assert_container_running host: :vm3, name: "app-jobs-#{second_version}"
+    assert_container_not_running host: :vm1, name: "app-web-#{first_version}"
+    assert_container_not_running host: :vm2, name: "app-web-#{first_version}"
+    assert_container_not_running host: :vm3, name: "app-workers-#{first_version}"
+  end
+
   private
     def assert_local_env_file(contents)
       assert_equal contents, deployer_exec("cat .env", capture: true)
@@ -139,7 +166,7 @@ class MainTest < IntegrationTest
       assert vm1_container_ids.any?
     end
 
-    def assert_container_running(host:, name:)
-      assert docker_compose("exec #{host} docker ps --filter=name=#{name} -q", capture: true).strip.present?
+    def rename_roles
+      deployer_exec "./rename_roles.sh #{@app}", workdir: "/"
     end
 end