Turn Environment into a standard registry

Author: solnic

lib/rom/compat.rb

@@ -18,24 +18,11 @@ def relation_classes(gateway = nil)
       gw_name = gateway.is_a?(Symbol) ? gateway : gateways_map[gateway]
       classes.select { |rel| rel.gateway == gw_name }
     end
-  end
 
-  module Gateways
     # @api private
-    class Environment
-      # @api private
-      # @deprecated
-      def gateways_map
-        @gateways_map ||= gateways.map { |gateway| [gateway, gateway.name] }.to_h
-      end
-
-      alias_method :values, :to_a
-
-      # @api private
-      # @deprecated
-      def keys
-        map(&:name)
-      end
+    # @deprecated
+    def gateways_map
+      @gateways_map ||= gateways.to_a.map(&:reverse).to_h
     end
   end
 end

lib/rom/configuration.rb

@@ -3,11 +3,11 @@
 require "forwardable"
 
 require "rom/support/notifications"
-require "rom/gateways/environment"
 require "rom/setup"
 require "rom/configuration_dsl"
 require "rom/support/configurable"
 require "rom/support/inflector"
+require "rom/gateway_registry"
 require "rom/relation_registry"
 
 module ROM
@@ -29,7 +29,7 @@ class Configuration
     NoDefaultAdapterError = Class.new(StandardError)
 
     # @!attribute [r] gateways
-    #   @return [Gateways::Environment] Configured runtime gateways
+    #   @return [GatewayRegistry] Configured runtime gateways
     attr_reader :gateways
 
     # @!attribute [r] setup
@@ -65,16 +65,17 @@ def initialize(*args, &block)
       @setup = Setup.new
       @cache = Cache.new
 
+      config.gateways = Config.new
+      @gateways = GatewayRegistry.new({}, cache: cache, config: config.gateways)
+
       configure(*args, &block)
 
       @relations = RelationRegistry.build
     end
 
     # @api public
     def configure(*args)
-      if args.empty?
-        config.gateways = Config.new
-      else
+      unless args.empty?
         gateways_config = args.first.is_a?(Hash) ? args.first : {default: args}
 
         gateways_config.each do |name, value|
@@ -91,7 +92,7 @@ def configure(*args)
         end
       end
 
-      @gateways = Gateways::Environment.new(config.gateways)
+      load_gateways
 
       yield(self) if block_given?
 
@@ -142,7 +143,7 @@ def respond_to?(name, include_all = false)
 
     # @api private
     def default_gateway
-      @default_gateway ||= gateways[:default]
+      @default_gateway ||= gateways[:default] if gateways.key?(:default)
     end
 
     # @api private
@@ -170,6 +171,17 @@ def command_compiler
 
     private
 
+    # @api private
+    def load_gateways
+      config.gateways.each do |name, gateway_config|
+        gateway = gateway_config.adapter.is_a?(Gateway) ?
+          gateway_config.adapter : Gateway.setup(gateway_config.adapter, gateway_config)
+        gateway.instance_variable_set(:"@name", name)
+
+        gateways.add(name, gateway)
+      end
+    end
+
     # @api private
     def load_config(config, hash)
       hash.each do |key, value|

lib/rom/constants.rb

@@ -20,6 +20,7 @@ def initialize(adapter, component)
   end
 
   EnvAlreadyFinalizedError = Class.new(StandardError)
+  GatewayAlreadyDefinedError = Class.new(StandardError)
   RelationAlreadyDefinedError = Class.new(StandardError)
   CommandAlreadyDefinedError = Class.new(StandardError)
   MapperAlreadyDefinedError = Class.new(StandardError)

lib/rom/container.rb

@@ -159,7 +159,7 @@ def commands
     #
     # @api public
     def disconnect
-      gateways.each(&:disconnect)
+      gateways.each_value(&:disconnect)
     end
   end
 end

lib/rom/gateway_registry.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require "rom/registry"
+
+module ROM
+  # @api private
+  class GatewayRegistry < Registry
+    # @!attribute [r] config
+    #   @return [Configurable::Config] Gateway configurations
+    option :config
+
+    # @api private
+    def add(key, gateway)
+      raise GatewayAlreadyDefinedError, "+#{key}+ is already defined" if key?(key)
+
+      elements[key] = gateway
+    end
+  end
+end

lib/rom/gateways/environment.rb

@@ -49,7 +49,7 @@ def container(*args, &block)
         end
 
       # TODO: this is super-legacy and should be removed
-      configuration.gateways.each do |gateway|
+      configuration.gateways.each_value do |gateway|
         gateway_config = configuration.config.gateways[gateway.name]
         gateway_config.infer_relations = true unless gateway_config.key?(:infer_relations)
       end

lib/rom/global.rb

@@ -80,6 +80,26 @@ def each(&block)
       elements.each(&block)
     end
 
+    # @api private
+    def each_key(&block)
+      elements.each_key(&block)
+    end
+
+    # @api private
+    def each_value(&block)
+      elements.each_value(&block)
+    end
+
+    # @api private
+    def keys
+      elements.keys
+    end
+
+    # @api private
+    def values
+      elements.values
+    end
+
     # @api private
     def key?(name)
       !name.nil? && elements.key?(name.to_sym)

lib/rom/registry.rb

@@ -2,10 +2,12 @@
 
 require "spec_helper"
 
-RSpec.describe ROM::Gateways::Environment do
-  let(:gateways) { ROM::Configuration.new(*params).gateways }
+RSpec.describe ROM::Configuration do
+  subject(:config) { ROM::Configuration.new(*params) }
+
+  let(:gateways) { config.gateways }
+  let(:gateways_map) { config.gateways_map }
   let(:params) { [] }
-  let(:gateways_map) { gateways.gateways_map }
 
   context "with an adapter identifier" do
     let(:params) { [:memory] }
@@ -91,7 +93,7 @@ def initialize(settings = {})
     let(:params) { [gateway] }
 
     it "configures the gateways hash" do
-      expect(gateways.keys).to eq([:default])
+      expect(gateways.keys).to eql([:default])
       expect(gateways[:default]).to be(gateway)
     end
   end

spec/compat/unit/rom/gateways/environment_spec.rb

@@ -119,7 +119,7 @@ def orange?
     let(:container) { ROM.container(configuration) }
 
     it "builds empty gateways" do
-      expect(container.gateways.map(&:name)).to be_empty
+      expect(container.gateways.keys).to be_empty
     end
 
     it "builds empty relations" do