Allow running detached app commands and follow logs by container ID

lib/kamal/cli/app.rb

@@ -94,9 +94,15 @@ def details
   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"
   option :env, aliases: "-e", type: :hash, desc: "Set environment variables for the command"
+  option :detach, type: :boolean, default: false, desc: "Execute command in a detached container"
   def exec(*cmd)
+    if (incompatible_options = [ :interactive, :reuse ].select { |key| options[:detach] && options[key] }.presence)
+      raise ArgumentError, "Detach is not compatible with #{incompatible_options.join(" or ")}"
+    end
+
     cmd = Kamal::Utils.join_commands(cmd)
     env = options[:env]
+    detach = options[:detach]
     case
     when options[:interactive] && options[:reuse]
       say "Get current version of running container...", :magenta unless options[:version]
@@ -138,7 +144,7 @@ def exec(*cmd)
 
           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, host: host).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, detach: detach))
           end
         end
       end
@@ -189,12 +195,14 @@ def images
   option :grep_options, aliases: "-o", desc: "Additional options supplied to grep"
   option :follow, aliases: "-f", desc: "Follow log on primary server (or specific host set by --hosts)"
   option :skip_timestamps, type: :boolean, aliases: "-T", desc: "Skip appending timestamps to logging output"
+  option :container_id, desc: "Docker container ID to fetch logs"
   def logs
     # FIXME: Catch when app containers aren't running
 
     grep = options[:grep]
     grep_options = options[:grep_options]
     since = options[:since]
+    container_id = options[:container_id]
     timestamps = !options[:skip_timestamps]
 
     if options[:follow]
@@ -207,8 +215,8 @@ def logs
         role = KAMAL.roles_on(KAMAL.primary_host).first
 
         app = KAMAL.app(role: role, host: host)
-        info app.follow_logs(host: KAMAL.primary_host, timestamps: timestamps, lines: lines, grep: grep, grep_options: grep_options)
-        exec app.follow_logs(host: KAMAL.primary_host, timestamps: timestamps, lines: lines, grep: grep, grep_options: grep_options)
+        info app.follow_logs(host: KAMAL.primary_host, container_id: container_id, timestamps: timestamps, lines: lines, grep: grep, grep_options: grep_options)
+        exec app.follow_logs(host: KAMAL.primary_host, container_id: container_id, timestamps: timestamps, lines: lines, grep: grep, grep_options: grep_options)
       end
     else
       lines = options[:lines].presence || ((since || grep) ? nil : 100) # Default to 100 lines if since or grep isn't set
@@ -218,7 +226,7 @@ def logs
 
         roles.each do |role|
           begin
-            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).logs(timestamps: timestamps, since: since, lines: lines, grep: grep, grep_options: grep_options))
+            puts_by_host host, capture_with_info(*KAMAL.app(role: role, host: host).logs(container_id: container_id, timestamps: timestamps, since: since, lines: lines, grep: grep, grep_options: grep_options))
           rescue SSHKit::Command::Failed
             puts_by_host host, "Nothing found"
           end

lib/kamal/cli/app/boot.rb

@@ -91,7 +91,7 @@ def close_barrier
       if barrier.close
         info "First #{KAMAL.primary_role} container is unhealthy on #{host}, not booting any other roles"
         begin
-          error capture_with_info(*app.logs(version: version))
+          error capture_with_info(*app.logs(container_id: app.container_id_for_version(version)))
           error capture_with_info(*app.container_health_log(version: version))
         rescue SSHKit::Command::Failed
           error "Could not fetch logs for #{version}"

lib/kamal/commands/app/execution.rb

@@ -7,13 +7,15 @@ def execute_in_existing_container(*command, interactive: false, env:)
       *command
   end
 
-  def execute_in_new_container(*command, interactive: false, env:)
+  def execute_in_new_container(*command, interactive: false, detach: false, env:)
     docker :run,
       ("-it" if interactive),
-      "--rm",
+      ("--detach" if detach),
+      ("--rm" unless detach),
       "--network", "kamal",
       *role&.env_args(host),
       *argumentize("--env", env),
+      *role.logging_args,
       *config.volume_args,
       *role&.option_args,
       config.absolute_image,

lib/kamal/commands/app/logging.rb

@@ -1,15 +1,15 @@
 module Kamal::Commands::App::Logging
-  def logs(version: nil, timestamps: true, since: nil, lines: nil, grep: nil, grep_options: nil)
+  def logs(container_id: nil, timestamps: true, since: nil, lines: nil, grep: nil, grep_options: nil)
     pipe \
-      version ? container_id_for_version(version) : current_running_container_id,
+      container_id ? "echo #{container_id}" : current_running_container_id,
       "xargs docker logs#{" --timestamps" if timestamps}#{" --since #{since}" if since}#{" --tail #{lines}" if lines} 2>&1",
       ("grep '#{grep}'#{" #{grep_options}" if grep_options}" if grep)
   end
 
-  def follow_logs(host:, timestamps: true, lines: nil, grep: nil, grep_options: nil)
+  def follow_logs(host:, container_id: nil, timestamps: true, lines: nil, grep: nil, grep_options: nil)
     run_over_ssh \
       pipe(
-        current_running_container_id,
+        container_id ? "echo #{container_id}" : current_running_container_id,
         "xargs docker logs#{" --timestamps" if timestamps}#{" --tail #{lines}" if lines} --follow 2>&1",
         (%(grep "#{grep}"#{" #{grep_options}" if grep_options}) if grep)
       ),

test/cli/app_test.rb

@@ -263,13 +263,37 @@ class CliAppTest < CliTestCase
 
   test "exec" do
     run_command("exec", "ruby -v").tap do |output|
-      assert_match "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env dhh/app:latest ruby -v", output
+      assert_match "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" dhh/app:latest ruby -v", output
     end
   end
 
   test "exec separate arguments" do
     run_command("exec", "ruby", " -v").tap do |output|
-      assert_match "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env dhh/app:latest ruby -v", output
+      assert_match "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" dhh/app:latest ruby -v", output
+    end
+  end
+
+  test "exec detach" do
+    run_command("exec", "--detach", "ruby -v").tap do |output|
+      assert_match "docker run --detach --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" dhh/app:latest ruby -v", output
+    end
+  end
+
+  test "exec detach with reuse" do
+    assert_raises(ArgumentError, "Detach is not compatible with reuse") do
+      run_command("exec", "--detach", "--reuse", "ruby -v")
+    end
+  end
+
+  test "exec detach with interactive" do
+    assert_raises(ArgumentError, "Detach is not compatible with interactive") do
+      run_command("exec", "--interactive", "--detach", "ruby -v")
+    end
+  end
+
+  test "exec detach with interactive and reuse" do
+    assert_raises(ArgumentError, "Detach is not compatible with interactive or reuse") do
+      run_command("exec", "--interactive", "--detach", "--reuse", "ruby -v")
     end
   end
 
@@ -282,7 +306,7 @@ class CliAppTest < CliTestCase
 
   test "exec interactive" do
     SSHKit::Backend::Abstract.any_instance.expects(:exec)
-      .with("ssh -t root@1.1.1.1 -p 22 'docker run -it --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env dhh/app:latest ruby -v'")
+      .with("ssh -t root@1.1.1.1 -p 22 'docker run -it --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" dhh/app:latest ruby -v'")
     run_command("exec", "-i", "ruby -v").tap do |output|
       assert_match "Get most recent version available as an image...", output
       assert_match "Launching interactive command with version latest via SSH from new container on 1.1.1.1...", output
@@ -329,6 +353,13 @@ class CliAppTest < CliTestCase
     assert_match "sh -c '\\''docker ps --latest --quiet --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 --quiet --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting'\\'' | head -1 | xargs docker logs --timestamps --tail 10 --follow 2>&1", run_command("logs", "--follow")
   end
 
+  test "logs with follow and container_id" do
+    SSHKit::Backend::Abstract.any_instance.stubs(:exec)
+      .with("ssh -t root@1.1.1.1 -p 22 'echo ID123 | xargs docker logs --timestamps --tail 10 --follow 2>&1'")
+
+    assert_match "echo ID123 | xargs docker logs --timestamps --tail 10 --follow 2>&1", run_command("logs", "--follow", "--container-id", "ID123")
+  end
+
   test "logs with follow and grep" do
     SSHKit::Backend::Abstract.any_instance.stubs(:exec)
       .with("ssh -t root@1.1.1.1 -p 22 'sh -c '\\''docker ps --latest --quiet --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 --quiet --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting'\\'' | head -1 | xargs docker logs --timestamps --follow 2>&1 | grep \"hey\"'")

test/commands/app_test.rb

@@ -157,6 +157,12 @@ class CommandsAppTest < ActiveSupport::TestCase
       new_command.logs.join(" ")
   end
 
+  test "logs with container_id" do
+    assert_equal \
+      "echo C137 | xargs docker logs --timestamps 2>&1",
+      new_command.logs(container_id: "C137").join(" ")
+  end
+
   test "logs with since" do
     assert_equal \
       "sh -c 'docker ps --latest --quiet --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting --filter ancestor=$(docker image ls --filter reference=dhh/app:latest --format '\\''{{.ID}}'\\'') ; docker ps --latest --quiet --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting' | head -1 | xargs docker logs --timestamps --since 5m 2>&1",
@@ -204,6 +210,10 @@ class CommandsAppTest < ActiveSupport::TestCase
       "ssh -t root@app-1 -p 22 'sh -c '\\''docker ps --latest --quiet --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting --filter ancestor=$(docker image ls --filter reference=dhh/app:latest --format '\\''\\'\\'''\\''{{.ID}}'\\''\\'\\'''\\'') ; docker ps --latest --quiet --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting'\\'' | head -1 | xargs docker logs --timestamps --follow 2>&1'",
       new_command.follow_logs(host: "app-1")
 
+    assert_equal \
+      "ssh -t root@app-1 -p 22 'echo ID321 | xargs docker logs --timestamps --follow 2>&1'",
+      new_command.follow_logs(host: "app-1", container_id: "ID321")
+
     assert_equal \
       "ssh -t root@app-1 -p 22 'sh -c '\\''docker ps --latest --quiet --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 --quiet --filter label=service=app --filter label=role=web --filter status=running --filter status=restarting'\\'' | head -1 | xargs docker logs --timestamps --follow 2>&1 | grep \"Completed\"'",
       new_command.follow_logs(host: "app-1", grep: "Completed")
@@ -224,29 +234,43 @@ class CommandsAppTest < ActiveSupport::TestCase
 
   test "execute in new container" do
     assert_equal \
-      "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env dhh/app:999 bin/rails db:setup",
+      "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" 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 logging" do
+    @config[:logging] = { "driver" => "local", "options" => { "max-size" => "100m", "max-file" => "3" } }
+
+    assert_equal \
+      "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-driver \"local\" --log-opt max-size=\"100m\" --log-opt max-file=\"3\" 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 env" do
     assert_equal \
-      "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --env foo=\"bar\" dhh/app:999 bin/rails db:setup",
+      "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --env foo=\"bar\" --log-opt max-size=\"10m\" dhh/app:999 bin/rails db:setup",
       new_command.execute_in_new_container("bin/rails", "db:setup", env: { "foo" => "bar" }).join(" ")
   end
 
+  test "execute in new detached container" do
+    assert_equal \
+      "docker run --detach --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" dhh/app:999 bin/rails db:setup",
+      new_command.execute_in_new_container("bin/rails", "db:setup", detach: true, env: {}).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 --network kamal --env ENV1=\"value1\" --env-file .kamal/apps/app/env/roles/web.env dhh/app:999 bin/rails db:setup",
+      "docker run --rm --network kamal --env ENV1=\"value1\" --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" 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 \
-      "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --mount \"somewhere\" --cap-add dhh/app:999 bin/rails db:setup",
+      "docker run --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" --mount \"somewhere\" --cap-add dhh/app:999 bin/rails db:setup",
       new_command.execute_in_new_container("bin/rails", "db:setup", env: {}).join(" ")
   end
 
@@ -263,21 +287,21 @@ class CommandsAppTest < ActiveSupport::TestCase
   end
 
   test "execute in new container over ssh" do
-    assert_match %r{docker run -it --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env dhh/app:999 bin/rails c},
+    assert_match %r{docker run -it --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size="10m" dhh/app:999 bin/rails c},
       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 --network kamal --env ENV1=\"value1\" --env-file .kamal/apps/app/env/roles/web.env dhh/app:999 bin/rails c'",
+    assert_equal "ssh -t root@1.1.1.1 -p 22 'docker run -it --rm --network kamal --env ENV1=\"value1\" --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" 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 --network kamal --env-file .kamal/apps/app/env/roles/web.env --mount \"somewhere\" --cap-add dhh/app:999 bin/rails c},
+    assert_match %r{docker run -it --rm --network kamal --env-file .kamal/apps/app/env/roles/web.env --log-opt max-size=\"10m\" --mount \"somewhere\" --cap-add dhh/app:999 bin/rails c},
       new_command.execute_in_new_container_over_ssh("bin/rails", "c", env: {})
   end