Add a yaml configurator to register services

Rakefile

@@ -1,5 +1,6 @@
 require 'rake/testtask'
 
 Rake::TestTask.new do |test|
+  test.libs   << 'test'
   test.pattern = 'test/**/test_*.rb'
 end

examples/services.yml

@@ -0,0 +1,11 @@
+parameters:
+  mailer.transport: sendmail
+services:
+  my.mailer:
+    class: Mailer
+    calls:
+      - ['transport=', '%mailer.transport%']
+  newsletter:
+    class: NewsletterManager
+    arguments:
+      - '@my.mailer'

examples/yaml_configuration_file.rb

@@ -0,0 +1,29 @@
+require 'dependency_injection/container'
+require 'dependency_injection/loaders/yaml'
+
+c = DependencyInjection::Container.new
+loader = DependencyInjection::Loaders::Yaml.new(c)
+loader.load(File.join(File.dirname(File.expand_path(__FILE__)), 'services.yml'))
+
+class NewsletterManager
+  def initialize(mailer)
+    @mailer = mailer
+  end
+
+  def send_mail(message)
+    puts 'newletter'
+    @mailer.send_mail(message)
+  end
+end
+
+class Mailer
+  attr_accessor :transport
+
+  def send_mail(message)
+    puts "mail sent via #{self.transport}: #{message}"
+  end
+end
+
+c.get('newsletter').send_mail('Hello World')
+# => newletter
+#    mail sent via sendmail: Hello World

lib/dependency_injection/loaders/yaml.rb

@@ -0,0 +1,35 @@
+require 'yaml'
+
+module DependencyInjection
+  module Loaders
+    class Yaml
+      def initialize(container)
+        @container = container
+      end
+
+      def load(filename)
+        file = YAML::load_file(filename)
+        add_parameters(file['parameters']) if file['parameters']
+        add_services(file['services']) if file['services']
+      end
+
+    private
+
+      def add_parameters(parameters)
+        parameters.each { |name, value| @container.add_parameter(name, value) }
+      end
+
+      def add_services(services)
+        services.each { |name, parameters| add_service(name, parameters) }
+      end
+
+      def add_service(name, parameters)
+        definition = @container.register(name, parameters['class'])
+        definition.add_arguments(*parameters['arguments']) if parameters['arguments']
+        if parameters['calls']
+          parameters['calls'].each { |method_name, arguments| definition.add_method_call(method_name, *arguments) }
+        end
+      end
+    end
+  end
+end

test/dependency_injection/loaders/test_yaml.rb

@@ -0,0 +1,88 @@
+require 'test_helper'
+require 'dependency_injection/loaders/yaml'
+
+class TestYaml < Minitest::Test
+  def setup
+    @container   = mock
+    @yaml_loader = DependencyInjection::Loaders::Yaml.new(@container)
+  end
+
+  def test_loading_file_without_parameters
+    YAML.stubs(:load_file).with('services.yml').returns({ 'services' => [] })
+    @yaml_loader.expects(:add_parameters).never
+
+    @yaml_loader.load('services.yml')
+  end
+
+  def test_loading_file_with_parameters
+    YAML.stubs(:load_file).with('services.yml').returns({'parameters' => { 'key_1' => 'value_1' }, 'services' => [] })
+    @yaml_loader.expects(:add_parameters).with({ 'key_1' => 'value_1' })
+
+    @yaml_loader.load('services.yml')
+  end
+
+  def test_loading_file_without_services
+    YAML.stubs(:load_file).with('services.yml').returns({ 'parameters' => [] })
+    @yaml_loader.expects(:add_services).never
+
+    @yaml_loader.load('services.yml')
+  end
+
+  def test_loading_file_with_services
+    YAML.stubs(:load_file).with('services.yml').returns({ 'parameters' => {}, 'services' => { 'service_1' => { 'class' => 'MyKlass' }}})
+    @yaml_loader.expects(:add_services).with({ 'service_1' => { 'class' => 'MyKlass' }})
+
+    @yaml_loader.load('services.yml')
+  end
+
+  def test_adding_parameters
+    @container.expects(:add_parameter).with('key_1', 'value_1')
+    @container.expects(:add_parameter).with('key_2', 'value_2')
+
+    @yaml_loader.send(:add_parameters, { 'key_1' => 'value_1', 'key_2' => 'value_2' })
+  end
+
+  def test_adding_services
+    @yaml_loader.expects(:add_service).with('key_1', { 'param_1' => 'value_1', 'param_2' => 'value_2' })
+    @yaml_loader.expects(:add_service).with('key_2', { 'param_1' => 'value_1' })
+
+    @yaml_loader.send(:add_services, { 'key_1' => { 'param_1' => 'value_1', 'param_2' => 'value_2' },
+                                       'key_2' => { 'param_1' => 'value_1' }})
+  end
+
+  def test_adding_service_without_parameters
+    definition = mock
+    @container.stubs(:register).with('key_1', 'MyKlass').returns(definition)
+    definition.expects(:add_arguments).never
+
+    @yaml_loader.send(:add_service, 'key_1', { 'class' => 'MyKlass' })
+  end
+
+  def test_adding_service_with_parameters
+    definition = mock
+    @container.stubs(:register).with('key_1', 'MyKlass').returns(definition)
+    definition.expects(:add_arguments).with('arg_1', 'arg_2')
+
+    @yaml_loader.send(:add_service, 'key_1', { 'class' => 'MyKlass', 'arguments' => ['arg_1', 'arg_2'] })
+  end
+
+  def test_adding_service_without_method_calls
+    definition = mock
+    @container.stubs(:register).with('key_1', 'MyKlass').returns(definition)
+    definition.expects(:add_method_call).never
+
+    @yaml_loader.send(:add_service, 'key_1', { 'class' => 'MyKlass' })
+  end
+
+  def test_adding_service_with_method_calls
+    definition = mock
+    @container.stubs(:register).with('key_1', 'MyKlass').returns(definition)
+    definition.expects(:add_method_call).with('method_1', 'arg_1')
+    definition.expects(:add_method_call).with('method_2', 'arg_1', 'arg_2')
+    definition.expects(:add_method_call).with('method_3', %w(arg_1 arg_2))
+
+    @yaml_loader.send(:add_service, 'key_1', { 'class' => 'MyKlass', 'calls' => { 'method_1' => ['arg_1'],
+                                                                                  'method_2' => ['arg_1', 'arg_2'],
+                                                                                  'method_3' => [['arg_1', 'arg_2']] }})
+  end
+end

test/dependency_injection/test_container.rb

@@ -1,4 +1,4 @@
-require_relative '../test_helper'
+require 'test_helper'
 require 'dependency_injection/container'
 
 class TestContainer < Minitest::Test

test/dependency_injection/test_definition.rb

@@ -1,4 +1,4 @@
-require_relative '../test_helper'
+require 'test_helper'
 require 'dependency_injection/definition'
 
 class TestDefinition < Minitest::Test