Merge pull request #1355 from npezza93/local-docker-registry

Use local docker registry to push and pull app images

Author: djmb

lib/kamal/cli/build.rb

@@ -68,16 +68,18 @@ def push
 
   desc "pull", "Pull app image from registry onto servers"
   def pull
-    login_to_registry_remotely
-
-    if (first_hosts = mirror_hosts).any?
-      #  Pull on a single host per mirror first to seed them
-      say "Pulling image on #{first_hosts.join(", ")} to seed the #{"mirror".pluralize(first_hosts.count)}...", :magenta
-      pull_on_hosts(first_hosts)
-      say "Pulling image on remaining hosts...", :magenta
-      pull_on_hosts(KAMAL.app_hosts - first_hosts)
-    else
-      pull_on_hosts(KAMAL.app_hosts)
+    login_to_registry_remotely unless KAMAL.registry.local?
+
+    forward_local_registry_port do
+      if (first_hosts = mirror_hosts).any?
+        #  Pull on a single host per mirror first to seed them
+        say "Pulling image on #{first_hosts.join(", ")} to seed the #{"mirror".pluralize(first_hosts.count)}...", :magenta
+        pull_on_hosts(first_hosts)
+        say "Pulling image on remaining hosts...", :magenta
+        pull_on_hosts(KAMAL.app_hosts - first_hosts)
+      else
+        pull_on_hosts(KAMAL.app_hosts)
+      end
     end
   end
 
@@ -194,7 +196,11 @@ def pull_on_hosts(hosts)
 
     def login_to_registry_locally
       run_locally do
-        execute *KAMAL.registry.login
+        if KAMAL.registry.local?
+          execute *KAMAL.registry.setup
+        else
+          execute *KAMAL.registry.login
+        end
       end
     end
 
@@ -203,4 +209,14 @@ def login_to_registry_remotely
         execute *KAMAL.registry.login
       end
     end
+
+    def forward_local_registry_port(&block)
+      if KAMAL.config.registry.local?
+        Kamal::Cli::PortForwarding.
+          new(KAMAL.hosts, KAMAL.config.registry.local_port).
+          forward(&block)
+      else
+        yield
+      end
+    end
 end

lib/kamal/cli/main.rb

@@ -185,7 +185,7 @@ def remove
         invoke "kamal:cli:app:remove", [], options.without(:confirmed)
         invoke "kamal:cli:proxy:remove", [], options.without(:confirmed)
         invoke "kamal:cli:accessory:remove", [ "all" ], options
-        invoke "kamal:cli:registry:logout", [], options.without(:confirmed).merge(skip_local: true)
+        invoke "kamal:cli:registry:remove", [], options.without(:confirmed).merge(skip_local: true)
       end
     end
   end

lib/kamal/cli/port_forwarding.rb

@@ -0,0 +1,42 @@
+class Kamal::Cli::PortForwarding
+  attr_reader :hosts, :port
+
+  def initialize(hosts, port)
+    @hosts = hosts
+    @port = port
+  end
+
+  def forward
+    @done = false
+    forward_ports
+
+    yield
+  ensure
+    stop
+  end
+
+  private
+
+  def stop
+    @done = true
+    @threads.to_a.each(&:join)
+  end
+
+  def forward_ports
+    @threads = hosts.map do |host|
+      Thread.new do
+        Net::SSH.start(host, KAMAL.config.ssh.user, **{ proxy: KAMAL.config.ssh.proxy }.compact) do |ssh|
+          ssh.forward.remote(port, "localhost", port, "localhost")
+          ssh.loop(0.1) do
+            if @done
+              ssh.forward.cancel_remote(port, "localhost")
+              break
+            else
+              true
+            end
+          end
+        end
+      end
+    end
+  end
+end

lib/kamal/cli/registry.rb

@@ -1,19 +1,27 @@
 class Kamal::Cli::Registry < Kamal::Cli::Base
-  desc "login", "Log in to registry locally and remotely"
+  desc "setup", "Setup local registry or log in to remote registry locally and remotely"
   option :skip_local, aliases: "-L", type: :boolean, default: false, desc: "Skip local login"
   option :skip_remote, aliases: "-R", type: :boolean, default: false, desc: "Skip remote login"
-  def login
+  def setup
     ensure_docker_installed unless options[:skip_local]
 
-    run_locally    { execute *KAMAL.registry.login } unless options[:skip_local]
-    on(KAMAL.hosts) { execute *KAMAL.registry.login } unless options[:skip_remote]
+    if KAMAL.registry.local?
+      run_locally    { execute *KAMAL.registry.setup } unless options[:skip_local]
+    else
+      run_locally    { execute *KAMAL.registry.login } unless options[:skip_local]
+      on(KAMAL.hosts) { execute *KAMAL.registry.login } unless options[:skip_remote]
+    end
   end
 
-  desc "logout", "Log out of registry locally and remotely"
+  desc "remove", "Remove local registry or log out of remote registry locally and remotely"
   option :skip_local, aliases: "-L", type: :boolean, default: false, desc: "Skip local login"
   option :skip_remote, aliases: "-R", type: :boolean, default: false, desc: "Skip remote login"
-  def logout
-    run_locally    { execute *KAMAL.registry.logout } unless options[:skip_local]
-    on(KAMAL.hosts) { execute *KAMAL.registry.logout } unless options[:skip_remote]
+  def remove
+    if KAMAL.registry.local?
+      run_locally    { execute *KAMAL.registry.remove, raise_on_non_zero_exit: false } unless options[:skip_local]
+    else
+      run_locally    { execute *KAMAL.registry.logout } unless options[:skip_local]
+      on(KAMAL.hosts) { execute *KAMAL.registry.logout } unless options[:skip_remote]
+    end
   end
 end

lib/kamal/cli/templates/deploy.yml

@@ -25,13 +25,14 @@ proxy:
 
 # Credentials for your image host.
 registry:
+  server: localhost:5555
   # Specify the registry server, if you're not using Docker Hub
   # server: registry.digitalocean.com / ghcr.io / ...
-  username: my-user
+  # username: my-user
 
   # Always use an access token rather than real password (pulled from .kamal/secrets).
-  password:
-    - KAMAL_REGISTRY_PASSWORD
+  # password:
+  #   - KAMAL_REGISTRY_PASSWORD
 
 # Configure builder setup.
 builder:

lib/kamal/cli/templates/secrets

@@ -3,7 +3,7 @@
 # password manager, ENV, or a file. DO NOT ENTER RAW CREDENTIALS HERE! This file needs to be safe for git.
 
 # Option 1: Read secrets from the environment
-KAMAL_REGISTRY_PASSWORD=$KAMAL_REGISTRY_PASSWORD
+# KAMAL_REGISTRY_PASSWORD=$KAMAL_REGISTRY_PASSWORD
 
 # Option 2: Read secrets via a command
 # RAILS_MASTER_KEY=$(cat config/master.key)

lib/kamal/commander.rb

@@ -21,7 +21,7 @@ def reset
   end
 
   def config
-    @config ||= Kamal::Configuration.create_from(**@config_kwargs).tap do |config|
+    @config ||= Kamal::Configuration.create_from(**@config_kwargs.to_h).tap do |config|
       @config_kwargs = nil
       configure_sshkit_with(config)
     end

lib/kamal/commands/builder/local.rb

@@ -1,6 +1,15 @@
 class Kamal::Commands::Builder::Local < Kamal::Commands::Builder::Base
   def create
-    docker :buildx, :create, "--name", builder_name, "--driver=#{driver}" unless docker_driver?
+    return if docker_driver?
+
+    options =
+      if KAMAL.registry.local?
+        "--driver=#{driver} --driver-opt network=host"
+      else
+        "--driver=#{driver}"
+      end
+
+    docker :buildx, :create, "--name", builder_name, options
   end
 
   def remove
@@ -9,6 +18,10 @@ def remove
 
   private
     def builder_name
-      "kamal-local-#{driver}"
+      if KAMAL.registry.local?
+        "kamal-local-registry-#{driver}"
+      else
+        "kamal-local-#{driver}"
+      end
     end
 end

lib/kamal/commands/registry.rb

@@ -2,6 +2,8 @@ class Kamal::Commands::Registry < Kamal::Commands::Base
   def login(registry_config: nil)
     registry_config ||= config.registry
 
+    return if registry_config.local?
+
     docker :login,
       registry_config.server,
       "-u", sensitive(Kamal::Utils.escape_shell_value(registry_config.username)),
@@ -13,4 +15,24 @@ def logout(registry_config: nil)
 
     docker :logout, registry_config.server
   end
+
+  def setup(registry_config: nil)
+    registry_config ||= config.registry
+
+    combine \
+      docker(:start, "kamal-docker-registry"),
+      docker(:run, "--detach", "-p", "127.0.0.1:#{registry_config.local_port}:5000", "--name", "kamal-docker-registry", "registry:3"),
+      by: "||"
+  end
+
+  def remove
+    combine \
+      docker(:stop, "kamal-docker-registry"),
+      docker(:rm, "kamal-docker-registry"),
+      by: "&&"
+  end
+
+  def local?
+    config.registry.local?
+  end
 end

lib/kamal/configuration.rb

@@ -6,7 +6,7 @@
 require "net/ssh/proxy/jump"
 
 class Kamal::Configuration
-  delegate :service, :image, :labels, :hooks_path, to: :raw_config, allow_nil: true
+  delegate :service, :labels, :hooks_path, to: :raw_config, allow_nil: true
   delegate :argumentize, :optionize, to: Kamal::Utils
 
   attr_reader :destination, :raw_config, :secrets
@@ -157,6 +157,13 @@ def proxy_hosts
     (proxy_roles.flat_map(&:hosts) + proxy_accessories.flat_map(&:hosts)).uniq
   end
 
+  def image
+    name = raw_config&.image.presence
+    name ||= raw_config&.service if registry.local?
+
+    name
+  end
+
   def repository
     [ registry.server, image ].compact.join("/")
   end
@@ -282,10 +289,12 @@ def ensure_destination_if_required
     end
 
     def ensure_required_keys_present
-      %i[ service image registry ].each do |key|
+      %i[ service registry ].each do |key|
         raise Kamal::ConfigurationError, "Missing required configuration for #{key}" unless raw_config[key].present?
       end
 
+      raise Kamal::ConfigurationError, "Missing required configuration for image" if image.blank?
+
       if raw_config.servers.nil?
         raise Kamal::ConfigurationError, "No servers or accessories specified" unless raw_config.accessories.present?
       else