Merge pull request #748 from basecamp/latest-by-tag

Latest by tag

lib/kamal/cli/app.rb

@@ -9,9 +9,6 @@ class Kamal::Cli::App < Kamal::Cli::Base
 
           # Assets are prepared in a separate step to ensure they are on all hosts before booting
           on(KAMAL.hosts) do
-            execute *KAMAL.auditor.record("Tagging #{KAMAL.config.absolute_image} as the latest image"), verbosity: :debug
-            execute *KAMAL.app.tag_current_image_as_latest
-
             KAMAL.roles_on(host).each do |role|
               Kamal::Cli::App::PrepareAssets.new(host, role, self).run
             end
@@ -22,6 +19,11 @@ class Kamal::Cli::App < Kamal::Cli::Base
               Kamal::Cli::App::Boot.new(host, role, version, self).run
             end
           end
+
+          on(KAMAL.hosts) do |host|
+            execute *KAMAL.auditor.record("Tagging #{KAMAL.config.absolute_image} as the latest image"), verbosity: :debug
+            execute *KAMAL.app.tag_latest_image
+          end
         end
       end
     end
@@ -138,7 +140,10 @@ class Kamal::Cli::App < Kamal::Cli::Base
         roles = KAMAL.roles_on(host)
 
         roles.each do |role|
-          cli.send(:stale_versions, host: host, role: role).each do |version|
+          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 ]
+
+          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
@@ -274,18 +279,7 @@ class Kamal::Cli::App < Kamal::Cli::Base
       version.presence
     end
 
-    def stale_versions(host:, role:)
-      versions = nil
-      on(host) do
-        versions = \
-          capture_with_info(*KAMAL.app(role: role).list_versions, raise_on_non_zero_exit: false)
-          .split("\n")
-          .drop(1)
-      end
-      versions
-    end
-
     def version_or_latest
-      options[:version] || "latest"
+      options[:version] || KAMAL.config.latest_tag
     end
 end

lib/kamal/commands/app.rb

@@ -49,7 +49,7 @@ class Kamal::Commands::App < Kamal::Commands::Base
 
 
   def current_running_container_id
-    docker :ps, "--quiet", *filter_args(statuses: ACTIVE_DOCKER_STATUSES), "--latest"
+    current_running_container(format: "--quiet")
   end
 
   def container_id_for_version(version, only_running: false)
@@ -57,13 +57,15 @@ class Kamal::Commands::App < Kamal::Commands::Base
   end
 
   def current_running_version
-    list_versions("--latest", statuses: ACTIVE_DOCKER_STATUSES)
+    pipe \
+      current_running_container(format: "--format '{{.Names}}'"),
+      extract_version_from_name
   end
 
   def list_versions(*docker_args, statuses: nil)
     pipe \
       docker(:ps, *filter_args(statuses: statuses), *docker_args, "--format", '"{{.Names}}"'),
-      %(while read line; do echo ${line##{role.container_prefix}-}; done) # Extract SHA from "service-role-dest-SHA"
+      extract_version_from_name
   end
 
 
@@ -81,10 +83,33 @@ class Kamal::Commands::App < Kamal::Commands::Base
       [ role.container_prefix, version || config.version ].compact.join("-")
     end
 
+    def latest_image_id
+      docker :image, :ls, *argumentize("--filter", "reference=#{config.latest_image}"), "--format", "'{{.ID}}'"
+    end
+
+    def current_running_container(format:)
+      pipe \
+        shell(chain(latest_image_container(format: format), latest_container(format: format))),
+        [ :head, "-1" ]
+    end
+
+    def latest_image_container(format:)
+      latest_container format: format, filters: [ "ancestor=$(#{latest_image_id.join(" ")})" ]
+    end
+
+    def latest_container(format:, filters: nil)
+      docker :ps, "--latest", *format, *filter_args(statuses: ACTIVE_DOCKER_STATUSES), argumentize("--filter", filters)
+    end
+
     def filter_args(statuses: nil)
       argumentize "--filter", filters(statuses: statuses)
     end
 
+    def extract_version_from_name
+      # Extract SHA from "service-role-dest-SHA"
+      %(while read line; do echo ${line##{role.container_prefix}-}; done)
+    end
+
     def filters(statuses: nil)
       [ "label=service=#{config.service}" ].tap do |filters|
         filters << "label=destination=#{config.destination}" if config.destination

lib/kamal/commands/app/assets.rb

@@ -5,7 +5,7 @@ module Kamal::Commands::App::Assets
     combine \
       make_directory(role.asset_extracted_path),
       [ *docker(:stop, "-t 1", asset_container, "2> /dev/null"), "|| true" ],
-      docker(:run, "--name", asset_container, "--detach", "--rm", config.latest_image, "sleep 1000000"),
+      docker(:run, "--name", asset_container, "--detach", "--rm", config.absolute_image, "sleep 1000000"),
       docker(:cp, "-L", "#{asset_container}:#{role.asset_path}/.", role.asset_extracted_path),
       docker(:stop, "-t 1", asset_container),
       by: "&&"

lib/kamal/commands/app/images.rb

@@ -7,7 +7,7 @@ module Kamal::Commands::App::Images
     docker :image, :prune, "--all", "--force", *filter_args
   end
 
-  def tag_current_image_as_latest
+  def tag_latest_image
     docker :tag, config.absolute_image, config.latest_image
   end
 end

lib/kamal/commands/base.rb

@@ -71,7 +71,7 @@ module Kamal::Commands
       end
 
       def shell(command)
-        [ :sh, "-c", "'#{command.flatten.join(" ").gsub("'", "'\\''")}'" ]
+        [ :sh, "-c", "'#{command.flatten.join(" ").gsub("'", "'\\\\''")}'" ]
       end
 
       def docker(*args)

lib/kamal/configuration.rb

@@ -128,7 +128,11 @@ class Kamal::Configuration
   end
 
   def latest_image
-    "#{repository}:latest"
+    "#{repository}:#{latest_tag}"
+  end
+
+  def latest_tag
+    [ "latest", *destination ].join("-")
   end
 
   def service_with_version