support custom proxy image

- Allow users to specify custom proxy image repository instead of using default basecamp/kamal-proxy
- Help users in regions where Docker Hub access is restricted (e.g. China) to pull proxy image from cloud vendor repositories
- Move proxy related configurations from configuration to proxy

Author: songjiz

lib/kamal/cli/proxy.rb

@@ -13,32 +13,34 @@ def boot
 
         version = capture_with_info(*KAMAL.proxy.version).strip.presence
 
-        if version && Kamal::Utils.older_version?(version, Kamal::Configuration::PROXY_MINIMUM_VERSION)
-          raise "kamal-proxy version #{version} is too old, run `kamal proxy reboot` in order to update to at least #{Kamal::Configuration::PROXY_MINIMUM_VERSION}"
+        if version && Kamal::Utils.older_version?(version, Kamal::Configuration::Proxy::MINIMUM_VERSION)
+          raise "kamal-proxy version #{version} is too old, run `kamal proxy reboot` in order to update to at least #{Kamal::Configuration::Proxy::MINIMUM_VERSION}"
         end
         execute *KAMAL.proxy.start_or_run
       end
     end
   end
 
   desc "boot_config <set|get|reset>", "Manage kamal-proxy boot configuration"
+  option :image, type: :string, default: Kamal::Configuration::Proxy::DEFAULT_IMAGE, desc: "Name of the image"
   option :publish, type: :boolean, default: true, desc: "Publish the proxy ports on the host"
-  option :http_port, type: :numeric, default: Kamal::Configuration::PROXY_HTTP_PORT, desc: "HTTP port to publish on the host"
-  option :https_port, type: :numeric, default: Kamal::Configuration::PROXY_HTTPS_PORT, desc: "HTTPS port to publish on the host"
-  option :log_max_size, type: :string, default: Kamal::Configuration::PROXY_LOG_MAX_SIZE, desc: "Max size of proxy logs"
+  option :http_port, type: :numeric, default: Kamal::Configuration::Proxy::HTTP_PORT, desc: "HTTP port to publish on the host"
+  option :https_port, type: :numeric, default: Kamal::Configuration::Proxy::HTTPS_PORT, desc: "HTTPS port to publish on the host"
+  option :log_max_size, type: :string, default: Kamal::Configuration::Proxy::LOG_MAX_SIZE, desc: "Max size of proxy logs"
   option :docker_options, type: :array, default: [], desc: "Docker options to pass to the proxy container", banner: "option=value option2=value2"
   def boot_config(subcommand)
     case subcommand
     when "set"
       boot_options = [
-        *(KAMAL.config.proxy_publish_args(options[:http_port], options[:https_port]) if options[:publish]),
-        *(KAMAL.config.proxy_logging_args(options[:log_max_size])),
-        *options[:docker_options].map { |option| "--#{option}" }
+        *(KAMAL.config.proxy.publish_args(options[:http_port], options[:https_port]) if options[:publish]),
+        *(KAMAL.config.proxy.logging_args(options[:log_max_size])),
+        *options[:docker_options].map { |option| "--#{option}" },
+        options[:image]
       ]
 
       on(KAMAL.proxy_hosts) do |host|
         execute(*KAMAL.proxy.ensure_proxy_directory)
-        upload! StringIO.new(boot_options.join(" ")), KAMAL.config.proxy_options_file
+        upload! StringIO.new(boot_options.join(" ")), KAMAL.config.proxy.options_file
       end
     when "get"
       on(KAMAL.proxy_hosts) do |host|

lib/kamal/commands/app/proxy.rb

@@ -1,6 +1,4 @@
 module Kamal::Commands::App::Proxy
-  delegate :proxy_container_name, to: :config
-
   def deploy(target:)
     proxy_exec :deploy, role.container_prefix, *role.proxy.deploy_command_args(target: target)
   end
@@ -11,6 +9,6 @@ def remove
 
   private
     def proxy_exec(*command)
-      docker :exec, proxy_container_name, "kamal-proxy", *command
+      docker :exec, config.proxy.container_name, "kamal-proxy", *command
     end
 end

lib/kamal/commands/proxy.rb

@@ -8,8 +8,7 @@ def run
       "--detach",
       "--restart", "unless-stopped",
       "--volume", "kamal-proxy-config:/home/kamal-proxy/.config/kamal-proxy",
-      "\$\(#{get_boot_options.join(" ")}\)",
-      config.proxy_image
+      "\$\(#{get_boot_options.join(" ")}\)"
   end
 
   def start
@@ -65,23 +64,23 @@ def cleanup_traefik
   end
 
   def ensure_proxy_directory
-    make_directory config.proxy_directory
+    make_directory config.proxy.directory
   end
 
   def remove_proxy_directory
-    remove_directory config.proxy_directory
+    remove_directory config.proxy.directory
   end
 
   def get_boot_options
-    combine [ :cat, config.proxy_options_file ], [ :echo, "\"#{config.proxy_options_default.join(" ")}\"" ], by: "||"
+    combine [ :cat, config.proxy.options_file ], [ :echo, "\"#{config.proxy.options_default.join(" ")}\"" ], by: "||"
   end
 
   def reset_boot_options
-    remove_file config.proxy_options_file
+    remove_file config.proxy.options_file
   end
 
   private
     def container_name
-      config.proxy_container_name
+      config.proxy.container_name
     end
 end

lib/kamal/configuration.rb

@@ -14,11 +14,6 @@ class Kamal::Configuration
 
   include Validation
 
-  PROXY_MINIMUM_VERSION = "v0.8.2"
-  PROXY_HTTP_PORT = 80
-  PROXY_HTTPS_PORT = 443
-  PROXY_LOG_MAX_SIZE = "10m"
-
   class << self
     def create_from(config_file:, destination: nil, version: nil)
       ENV["KAMAL_DESTINATION"] = destination
@@ -82,7 +77,6 @@ def initialize(raw_config, destination: nil, version: nil, validate: true)
     ensure_unique_hosts_for_ssl_roles
   end
 
-
   def version=(version)
     @declared_version = version
   end
@@ -106,7 +100,6 @@ def minimum_version
     raw_config.minimum_version
   end
 
-
   def roles
     servers.roles
   end
@@ -119,7 +112,6 @@ def accessory(name)
     accessories.detect { |a| a.name == name.to_s }
   end
 
-
   def all_hosts
     (roles + accessories).flat_map(&:hosts).uniq
   end
@@ -180,7 +172,6 @@ def retain_containers
     raw_config.retain_containers || 5
   end
 
-
   def volume_args
     if raw_config.volumes.present?
       argumentize "--volume", raw_config.volumes
@@ -193,7 +184,6 @@ def logging_args
     logging.args
   end
 
-
   def readiness_delay
     raw_config.readiness_delay || 7
   end
@@ -206,7 +196,6 @@ def drain_timeout
     raw_config.drain_timeout || 30
   end
 
-
   def run_directory
     ".kamal"
   end
@@ -227,7 +216,6 @@ def assets_directory
     File.join app_directory, "assets"
   end
 
-
   def hooks_path
     raw_config.hooks_path || ".kamal/hooks"
   end
@@ -236,7 +224,6 @@ def asset_path
     raw_config.asset_path
   end
 
-
   def env_tags
     @env_tags ||= if (tags = raw_config.env["tags"])
       tags.collect { |name, config| Env::Tag.new(name, config: config, secrets: secrets) }
@@ -249,35 +236,6 @@ def env_tag(name)
     env_tags.detect { |t| t.name == name.to_s }
   end
 
-  def proxy_publish_args(http_port, https_port)
-    argumentize "--publish", [ "#{http_port}:#{PROXY_HTTP_PORT}", "#{https_port}:#{PROXY_HTTPS_PORT}" ]
-  end
-
-  def proxy_logging_args(max_size)
-    argumentize "--log-opt", "max-size=#{max_size}" if max_size.present?
-  end
-
-  def proxy_options_default
-    [ *proxy_publish_args(PROXY_HTTP_PORT, PROXY_HTTPS_PORT), *proxy_logging_args(PROXY_LOG_MAX_SIZE) ]
-  end
-
-  def proxy_image
-    "basecamp/kamal-proxy:#{PROXY_MINIMUM_VERSION}"
-  end
-
-  def proxy_container_name
-    "kamal-proxy"
-  end
-
-  def proxy_directory
-    File.join run_directory, "proxy"
-  end
-
-  def proxy_options_file
-    File.join proxy_directory, "options"
-  end
-
-
   def to_h
     {
       roles: role_names,

lib/kamal/configuration/docs/proxy.yml

@@ -16,7 +16,6 @@
 # It is disabled by default on all other roles but can be enabled by setting
 # `proxy: true` or providing a proxy configuration.
 proxy:
-
   # Hosts
   #
   # The hosts that will be used to serve the app. The proxy will only route requests

lib/kamal/configuration/proxy.rb

@@ -1,8 +1,13 @@
 class Kamal::Configuration::Proxy
   include Kamal::Configuration::Validation
 
+  HTTP_PORT = 80
+  HTTPS_PORT = 443
+  LOG_MAX_SIZE = "10m"
+  MINIMUM_VERSION = "v0.8.2"
   DEFAULT_LOG_REQUEST_HEADERS = [ "Cache-Control", "Last-Modified", "User-Agent" ]
-  CONTAINER_NAME = "kamal-proxy"
+  DEFAULT_CONTAINER_NAME = "kamal-proxy"
+  DEFAULT_IMAGE = "basecamp/kamal-proxy:#{MINIMUM_VERSION}"
 
   delegate :argumentize, :optionize, to: Kamal::Utils
 
@@ -14,6 +19,10 @@ def initialize(config:, proxy_config:, context: "proxy")
     validate! @proxy_config, with: Kamal::Configuration::Validator::Proxy, context: context
   end
 
+  def container_name
+    DEFAULT_CONTAINER_NAME
+  end
+
   def app_port
     proxy_config.fetch("app_port", 80)
   end
@@ -47,6 +56,26 @@ def deploy_options
     }.compact
   end
 
+  def directory
+    File.join config.run_directory, "proxy"
+  end
+
+  def options_file
+    File.join directory, "options"
+  end
+
+  def publish_args(http_port, https_port)
+    argumentize "--publish", [ "#{http_port}:#{HTTP_PORT}", "#{https_port}:#{HTTPS_PORT}" ]
+  end
+
+  def logging_args(max_size)
+    argumentize "--log-opt", "max-size=#{max_size}" if max_size.present?
+  end
+
+  def options_default
+    [ *publish_args(HTTP_PORT, HTTPS_PORT), *logging_args(LOG_MAX_SIZE), DEFAULT_IMAGE ]
+  end
+
   def deploy_command_args(target:)
     optionize ({ target: "#{target}:#{app_port}" }).merge(deploy_options), with: "="
   end