Moving configuration away from singleton pattern

By making the configuration an instance variable it allowed more
flexibility in setting up configuration and testability. The
configuration object can be directly accessed in the app configuration
instead of using several translating setters. Testing the configuration
object is much simpler and doesn’t require resetting the state of the
object after complete testing.

CHANGELOG.md

@@ -12,6 +12,7 @@ Enhancements:
 * New path strategy to support `/v3/posts` style versioning, thanks [Michael Elfassy](https://github.com/elfassy)
 * Support Rails 4.1, thanks [Washington L Braga Jr](https://github.com/huoxito)
 * Added v1->v2 template renaming migration script
+* Improving configuration
 
 ## 1.3.0 (Sept 26, 2013)
 

README.md

@@ -43,6 +43,7 @@ gem install versioncake
 
 ## Upgrade v1.0 -> v2.0
 
+### Filename changes
 The major breaking change to require a bump to v2.0 was the order of the extensions. To avoid priority issues with the format (#14), the version number and the format have been swapped.
 
 `index.v1.json.jbuilder` -> `index.json.v1.jbuilder`
@@ -51,6 +52,17 @@ To make it easier to upgrade, run the following command to automatically rename
 
 `verisoncake migrate` or `verisoncake migrate path/to/views`
 
+### Configuration changes
+
+The configuration options for Version Cake have been namespaced and slightly renamed. The following is a mapping of the old names to the new names:
+
+| Old Name | New Name |
+| --------------------------------------- |:--------------------------------------------:|
+| config.view_versions                    | config.versioncake.supported_version_numbers |
+| config.view_version_extraction_strategy | config.versioncake.extraction_strategy       |
+| config.view_version_string              | config.versioncake.version_key               |
+| config.default_version                  | config.versioncake.default_version           |
+
 ## Example
 
 In this simple example we will outline the code that is introduced to support a change in a version.

lib/versioncake/configuration.rb

@@ -2,47 +2,47 @@
 require 'active_support/core_ext/array/wrap.rb'
 
 module VersionCake
-  module Configuration
+  class Configuration
 
     SUPPORTED_VERSIONS_DEFAULT = (1..10)
+    VERSION_KEY_DEFAULT = 'api_version'
 
-    mattr_reader :supported_version_numbers
+    attr_reader :extraction_strategies, :supported_version_numbers
+    attr_accessor :default_version, :version_key
 
-    mattr_accessor :extraction_strategies
-    self.extraction_strategies = []
-
-    mattr_accessor :default_version
-    self.default_version = nil
+    def initialize
+      @version_key                   = VERSION_KEY_DEFAULT
+      self.supported_version_numbers = SUPPORTED_VERSIONS_DEFAULT
+      self.extraction_strategy       = :query_parameter
+    end
 
-    def self.extraction_strategy=(val)
-      @@extraction_strategies.clear
+    def extraction_strategy=(val)
+      @extraction_strategies = []
       Array.wrap(val).each do |configured_strategy|
-        @@extraction_strategies << VersionCake::ExtractionStrategy.lookup(configured_strategy)
+        @extraction_strategies << VersionCake::ExtractionStrategy.lookup(configured_strategy)
       end
     end
 
-    def self.supported_version_numbers=(val)
-      @@supported_version_numbers = val.respond_to?(:to_a) ? val.to_a : Array.wrap(val)
-      @@supported_version_numbers.sort!.reverse!
+    def supported_version_numbers=(val)
+      @supported_version_numbers = val.respond_to?(:to_a) ? val.to_a : Array.wrap(val)
+      @supported_version_numbers.sort!.reverse!
     end
 
-    def self.supported_versions(requested_version_number=nil)
-      supported_version_numbers.collect do |supported_version_number|
+    def supported_versions(requested_version_number=nil)
+      @supported_version_numbers.collect do |supported_version_number|
         if requested_version_number.nil? || supported_version_number <= requested_version_number
           :"v#{supported_version_number}"
         end
       end
     end
 
-    def self.supports_version?(version)
-      supported_version_numbers.include? version
+    def supports_version?(version)
+      @supported_version_numbers.include? version
     end
 
-    def self.latest_version
-      supported_version_numbers.first
+    def latest_version
+      @supported_version_numbers.first
     end
 
-    self.extraction_strategy       = :query_parameter
-    self.supported_version_numbers = SUPPORTED_VERSIONS_DEFAULT
   end
 end

lib/versioncake/railtie.rb

@@ -1,23 +1,7 @@
 require 'rails'
 
-class ActionViewVersions < Rails::Railtie
-  initializer "view_versions" do |app|
-    ActiveSupport.on_load(:action_view) do
-      if app.config.respond_to?(:view_versions)
-        VersionCake::Configuration.supported_version_numbers = app.config.view_versions
-      end
-
-      if app.config.respond_to?(:view_version_extraction_strategy)
-        VersionCake::Configuration.extraction_strategy = app.config.view_version_extraction_strategy
-      end
-
-      if app.config.respond_to?(:view_version_string)
-        VersionCake::ExtractionStrategy.version_string = app.config.view_version_string
-      end
-
-      if app.config.respond_to?(:default_version)
-        VersionCake::Configuration.default_version = app.config.default_version
-      end
-    end
+module VersionCake
+  class Railtie < ::Rails::Railtie
+    config.versioncake = VersionCake::Configuration.new
   end
 end

lib/versioncake/strategies/extraction_strategy.rb

@@ -1,21 +1,17 @@
-if defined?(ActionPack::VERSION::MAJOR) && ActionPack::VERSION::MAJOR == 4 && ActionPack::VERSION::MINOR >= 1
-  require 'active_support/core_ext/module/attribute_accessors'
-else
-  require 'active_support/core_ext/class/attribute_accessors.rb'
-end
 require 'active_support/core_ext/string/inflections.rb'
 
 module VersionCake
   class ExtractionStrategy
 
-    cattr_accessor :version_string
-    @@version_string = 'api_version'
-
     def extract(request)
       version = execute(request)
       return version.to_i if version && /[0-9]+/.match(version)
     end
 
+    def version_key
+      VersionCake::Railtie.config.versioncake.version_key
+    end
+
     def execute(request)
       raise Exception, "ExtractionStrategy requires execute to be implemented"
     end

lib/versioncake/strategies/http_accept_parameter_strategy.rb

@@ -3,7 +3,7 @@ class HttpAcceptParameterStrategy < ExtractionStrategy
 
     def execute(request)
       if request.headers.key?("HTTP_ACCEPT") &&
-          match = request.headers["HTTP_ACCEPT"].match(/#{@@version_string}=([0-9]+)/)
+          match = request.headers["HTTP_ACCEPT"].match(/#{version_key}=([0-9]+)/)
         match[1]
       end
     end

lib/versioncake/strategies/http_header_strategy.rb

@@ -2,8 +2,8 @@ module VersionCake
   class HttpHeaderStrategy < ExtractionStrategy
 
     def execute(request)
-      if request.headers.key? "HTTP_X_#{@@version_string.upcase}"
-        request.headers["HTTP_X_#{@@version_string.upcase}"]
+      if request.headers.key? "HTTP_X_#{version_key.upcase}"
+        request.headers["HTTP_X_#{version_key.upcase}"]
       end
     end
 

lib/versioncake/strategies/path_parameter_strategy.rb

@@ -2,8 +2,8 @@ module VersionCake
   class PathParameterStrategy < ExtractionStrategy
 
     def execute(request)
-      if request.path_parameters.key? @@version_string.to_sym
-        request.path_parameters[@@version_string.to_sym]
+      if request.path_parameters.key? version_key.to_sym
+        request.path_parameters[version_key.to_sym]
       end
     end
 

lib/versioncake/strategies/query_parameter_strategy.rb

@@ -2,8 +2,8 @@ module VersionCake
   class QueryParameterStrategy < ExtractionStrategy
 
     def execute(request)
-      if request.query_parameters.key? @@version_string.to_sym
-        request.query_parameters[@@version_string.to_sym].to_s
+      if request.query_parameters.key? version_key.to_sym
+        request.query_parameters[version_key.to_sym].to_s
       end
     end
 

lib/versioncake/strategies/request_parameter_strategy.rb

@@ -2,8 +2,8 @@ module VersionCake
   class RequestParameterStrategy < ExtractionStrategy
 
     def execute(request)
-      if request.request_parameters.has_key? @@version_string.to_sym
-        request.request_parameters[@@version_string.to_sym]
+      if request.request_parameters.has_key? version_key.to_sym
+        request.request_parameters[version_key.to_sym]
       end
     end
 

lib/versioncake/versioned_request.rb

@@ -4,18 +4,22 @@ class VersionedRequest
 
     def initialize(request, version_override=nil)
       @version = version_override || extract_version(request)
-      @is_latest_version = @version == VersionCake::Configuration.latest_version
+      @is_latest_version = @version == config.latest_version
     end
 
     def supported_versions
-      VersionCake::Configuration.supported_versions(@version)
+      config.supported_versions(@version)
     end
 
     private
 
+    def config
+      VersionCake::Railtie.config.versioncake
+    end
+
     def apply_strategies(request)
       version = nil
-      VersionCake::Configuration.extraction_strategies.each do |strategy|
+      config.extraction_strategies.each do |strategy|
         version = strategy.extract(request)
         break unless version.nil?
       end
@@ -25,10 +29,10 @@ def apply_strategies(request)
     def extract_version(request)
       @extracted_version = apply_strategies(request)
       if @extracted_version.nil?
-        @version = VersionCake::Configuration.default_version || VersionCake::Configuration.latest_version
-      elsif VersionCake::Configuration.supports_version? @extracted_version
+        @version = config.default_version || config.latest_version
+      elsif config.supports_version? @extracted_version
         @version = @extracted_version
-      elsif @extracted_version > VersionCake::Configuration.latest_version
+      elsif @extracted_version > config.latest_version
         raise ActionController::RoutingError.new("No route match for version")
       else
         raise ActionController::RoutingError.new("Version is deprecated")

lib/versioncake/view_additions.rb

@@ -3,7 +3,7 @@
 # register an addition detail for the lookup context to understand,
 # this will allow us to have the versions available upon lookup in
 # the resolver.
-ActionView::LookupContext.register_detail(:versions){ VersionCake::Configuration.supported_versions }
+ActionView::LookupContext.register_detail(:versions){ VersionCake::Railtie.config.versioncake.supported_versions }
 
 ActionView::PathResolver.class_eval do
   # not sure why we are doing this yet, but looks like a good idea

test/config/application.rb

@@ -11,7 +11,8 @@ class Application < Rails::Application
     config.eager_load = false
 
     config.active_support.deprecation = :stderr
-    config.view_versions = (1..3)
-    config.view_version_extraction_strategy = [:http_header, :http_accept_parameter, :query_parameter, :request_parameter]
+
+    config.versioncake.supported_version_numbers = (1..3)
+    config.versioncake.extraction_strategy = [:http_header, :http_accept_parameter, :query_parameter, :request_parameter]
   end
 end

test/functional/custom_strategy_controller_test.rb

@@ -6,7 +6,7 @@ class CustomStrategyTest < ActionController::TestCase
   tests RendersController
 
   setup do
-    VersionCake::Configuration.stubs(:extraction_strategy => lambda { |request| 2 })
+    VersionCake::Configuration.any_instance.stubs(:extraction_strategy => lambda { |request| 2 })
   end
 
   test "renders version 2 of the partial based on the header Accept" do

test/functional/renders_controller_test.rb

@@ -30,7 +30,7 @@ class RendersControllerTest < ActionController::TestCase
   end
 
   test "exposes the default version when the version is not set default is set" do
-    VersionCake::Configuration.stubs(:default_version => 1)
+    VersionCake::Configuration.any_instance.stubs(:default_version => 1)
     get :index
     assert_equal 1, @controller.derived_version
   end
@@ -52,14 +52,13 @@ class RendersControllerTest < ActionController::TestCase
   end
 
   test "responds with 404 when the version is lower than the latest version, but not an available version" do
-    VersionCake::Configuration.stubs(:supported_version_numbers => [2,3])
     assert_raise ActionController::RoutingError do
-      get :index, "api_version" => "1"
+      get :index, "api_version" => "0"
     end
   end
 
   test "render the default version version of the partial" do
-    VersionCake::Configuration.stubs(:default_version => 1)
+    VersionCake::Configuration.any_instance.stubs(:default_version => 1)
     get :index, "api_version" => "abc"
     assert_equal "template v1", @response.body
   end

test/unit/configuration_test.rb

@@ -2,48 +2,44 @@
 
 class ConfigurationTest < ActiveSupport::TestCase
   setup do
-    @previous_versions = VersionCake::Configuration.supported_version_numbers
-  end
-
-  teardown do
-    VersionCake::Configuration.supported_version_numbers = @previous_versions
+    @config = VersionCake::Configuration.new
   end
 
   test "supported_version_numbers can be set with range" do
-    VersionCake::Configuration.supported_version_numbers = (1..7)
-    assert_equal [7,6,5,4,3,2,1], VersionCake::Configuration.supported_version_numbers
+    @config.supported_version_numbers = (1..7)
+    assert_equal [7,6,5,4,3,2,1], @config.supported_version_numbers
   end
 
   test "supported_version_numbers can be set with an unordered array" do
-    VersionCake::Configuration.supported_version_numbers = [2,4,1,5,3,6,7]
-    assert_equal [7,6,5,4,3,2,1], VersionCake::Configuration.supported_version_numbers
+    @config.supported_version_numbers = [2,4,1,5,3,6,7]
+    assert_equal [7,6,5,4,3,2,1], @config.supported_version_numbers
   end
 
   test "supported_version_numbers can be set with a single value" do
-    VersionCake::Configuration.supported_version_numbers = 19
-    assert_equal [19], VersionCake::Configuration.supported_version_numbers
+    @config.supported_version_numbers = 19
+    assert_equal [19], @config.supported_version_numbers
   end
 
   test "supports_version? is only true for given supported versions" do
-    VersionCake::Configuration.supported_version_numbers = (1..7)
-    VersionCake::Configuration.supported_version_numbers.each do |supported_version|
-      assert VersionCake::Configuration.supports_version? supported_version
+    @config.supported_version_numbers = (1..7)
+    @config.supported_version_numbers.each do |supported_version|
+      assert @config.supports_version? supported_version
     end
   end
 
   test "supports_version? is not true for other versions" do
-    VersionCake::Configuration.supported_version_numbers = (1..7)
+    @config.supported_version_numbers = (1..7)
     [-2,-1,0,8,9,10].each do |unsupported_version|
-      assert !VersionCake::Configuration.supports_version?(unsupported_version)
+      assert !@config.supports_version?(unsupported_version)
     end
   end
 
   test "latest_version retrieves the highest supported version" do
-    VersionCake::Configuration.supported_version_numbers = [4,1,3,9,2,54]
-    assert_equal 54, VersionCake::Configuration.latest_version
+    @config.supported_version_numbers = [4,1,3,9,2,54]
+    assert_equal 54, @config.latest_version
   end
 
   test "default supported_version_numbers should be a logic set of version numbers" do
-    assert_equal (1..10), VersionCake::Configuration::SUPPORTED_VERSIONS_DEFAULT
+    assert_equal (1..10).to_a.reverse, @config.supported_version_numbers
   end
 end

test/unit/versioned_request_test.rb

@@ -22,7 +22,7 @@ class VersionedRequestTest < ActiveSupport::TestCase
 
   test "a request for a deprecated version raises an exception" do
     VersionCake::VersionedRequest.any_instance.stubs(:apply_strategies => 2)
-    VersionCake::Configuration.stubs(:supports_version? => false)
+    VersionCake::Configuration.any_instance.stubs(:supports_version? => false)
     assert_raise ActionController::RoutingError do
       VersionCake::VersionedRequest.new(stub())
     end