Make rollbacks role-aware

Rollbacks stopped working after https://github.com/mrsked/mrsk/pull/99.

We'll confirm that a container is available for the first role on the
primary host before attempting to rollback.

lib/mrsk/cli/main.rb

@@ -77,21 +77,26 @@ class Mrsk::Cli::Main < Mrsk::Cli::Base
     with_lock do
       MRSK.config.version = version
 
-      if container_name_available?(MRSK.config.service_with_version)
+      if container_available?(version)
         say "Start version #{version}, then wait #{MRSK.config.readiness_delay}s for app to boot before stopping the old version...", :magenta
 
         cli = self
         old_version = nil
 
         on(MRSK.hosts) do |host|
-          old_version = capture_with_info(*MRSK.app.current_running_version).strip.presence
+          roles = MRSK.roles_on(host)
 
-          execute *MRSK.app.start
+          roles.each do |role|
+            app = MRSK.app(role: role)
+            old_version = capture_with_info(*app.current_running_version).strip.presence
+
+            execute *app.start
 
             if old_version
               sleep MRSK.config.readiness_delay
 
-            execute *MRSK.app.stop(version: old_version), raise_on_non_zero_exit: false
+              execute *app.stop(version: old_version), raise_on_non_zero_exit: false
+            end
           end
         end
 
@@ -214,10 +219,15 @@ class Mrsk::Cli::Main < Mrsk::Cli::Base
   subcommand "lock", Mrsk::Cli::Lock
 
   private
-    def container_name_available?(container_name, host: MRSK.primary_host)
+    def container_available?(version, host: MRSK.primary_host)
-      container_names = nil
+      available = nil
-      on(host) { container_names = capture_with_info(*MRSK.app.list_container_names).split("\n") }
+
-      Array(container_names).include?(container_name)
+      on(host) do
+        first_role = MRSK.roles_on(host).first
+        available = capture_with_info(*MRSK.app(role: first_role).container_id_for_version(version)).present?
+      end
+
+      available
     end
 
     def deploy_options

test/cli/main_test.rb

@@ -120,32 +120,34 @@ class CliMainTest < CliTestCase
   end
 
   test "rollback bad version" do
+    # Mrsk::Cli::Main.any_instance.stubs(:container_available?).returns(false)
     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 /docker container ls --all --filter name=\^app-web-nonsense\$ --quiet/, 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)
+    Mrsk::Cli::Main.any_instance.stubs(:container_available?).returns(true)
-    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info).with(:docker, :ps, "--filter", "label=service=app", "--format", "\"{{.Names}}\"", "|", "sed 's/-/\\n/g'", "|", "tail -n 1").returns("version-to-rollback\n").at_least_once
+    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info).with(:docker, :ps, "--filter", "label=service=app", "--filter", "label=role=web", "--format", "\"{{.Names}}\"", "|", "sed 's/-/\\n/g'", "|", "tail -n 1").returns("version-to-rollback\n").at_least_once
+    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info).with(:docker, :ps, "--filter", "label=service=app", "--filter", "label=role=workers", "--format", "\"{{.Names}}\"", "|", "sed 's/-/\\n/g'", "|", "tail -n 1").returns("version-to-rollback\n").at_least_once
 
     run_command("rollback", "123", config_file: "deploy_with_accessories").tap do |output|
       assert_match "Start version 123", output
-      assert_match "docker start app-123", output
+      assert_match "docker start app-web-123", output
-      assert_match "docker container ls --all --filter name=^app-version-to-rollback$ --quiet | xargs docker stop", output, "Should stop the container that was previously running"
+      assert_match "docker container ls --all --filter name=^app-web-version-to-rollback$ --quiet | xargs docker stop", output, "Should stop the container that was previously running"
     end
   end
 
   test "rollback without old version" do
-    Mrsk::Cli::Main.any_instance.stubs(:container_name_available?).returns(true)
+    Mrsk::Cli::Main.any_instance.stubs(:container_available?).returns(true)
-    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info).with(:docker, :ps, "--filter", "label=service=app", "--format", "\"{{.Names}}\"", "|", "sed 's/-/\\n/g'", "|", "tail -n 1").returns("").at_least_once
+    SSHKit::Backend::Abstract.any_instance.expects(:capture_with_info).with(:docker, :ps, "--filter", "label=service=app", "--filter", "label=role=web", "--format", "\"{{.Names}}\"", "|", "sed 's/-/\\n/g'", "|", "tail -n 1").returns("").at_least_once
 
     run_command("rollback", "123").tap do |output|
       assert_match "Start version 123", output
-      assert_match "docker start app-123", output
+      assert_match "docker start app-web-123", output
       assert_no_match "docker stop", output
     end
   end