Added ActiveResource.format= which defaults to :xml but can also be set to :json [DHH]. Added one-off declarations of mock behavior [DHH]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7518 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activeresource/CHANGELOG

@@ -1,5 +1,30 @@
 *SVN*
 
+* Added one-off declarations of mock behavior [DHH]. Example:
+
+    Before:
+      ActiveResource::HttpMock.respond_to do |mock|
+        mock.get "/people/1.xml", {}, "<person><name>David</name></person>"
+      end
+      
+    Now:
+      ActiveResource::HttpMock.respond_to.get "/people/1.xml", {}, "<person><name>David</name></person>"
+
+* Added ActiveResource.format= which defaults to :xml but can also be set to :json [DHH]. Example:
+
+    class Person < ActiveResource::Base
+      self.site   = "http://app/"
+      self.format = :json
+    end
+    
+    person = Person.find(1) # => GET http://app/people/1.json
+    person.name = "David"
+    person.save             # => PUT http://app/people/1.json {name: "David"}
+    
+    Person.format = :xml
+    person.name = "Mary"
+    person.save             # => PUT http://app/people/1.json <person><name>Mary</name></person>    
+
 * Fix reload error when path prefix is used.  #8727 [Ian Warshak]
 
 * Remove ActiveResource::Struct because it hasn't proven very useful. Creating a new ActiveResource::Base subclass is often less code and always clearer.  #8612 [Josh Peek]

activeresource/lib/active_resource.rb

@@ -34,6 +34,7 @@ unless defined?(ActiveSupport)
   end
 end
 
+require 'active_resource/formats'
 require 'active_resource/base'
 require 'active_resource/validations'
 require 'active_resource/custom_methods'

activeresource/lib/active_resource/base.rb

@@ -155,7 +155,7 @@ module ActiveResource
       def site
         if defined?(@site)
           @site
-        elsif superclass != Object and superclass.site
+        elsif superclass != Object && superclass.site
           superclass.site.dup.freeze
         end
       end
@@ -167,12 +167,34 @@ module ActiveResource
         @site = site.nil? ? nil : create_site_uri_from(site)
       end
 
+      # Sets the format that attributes are sent and received in from a mime type reference. Example:
+      #
+      #   Person.format = :json
+      #   Person.find(1) # => GET /people/1.json
+      #
+      #   Person.format = ActiveResource::Formats::XmlFormat
+      #   Person.find(1) # => GET /people/1.xml
+      #
+      # Default format is :xml.
+      def format=(mime_type_reference_or_format)
+        format = mime_type_reference_or_format.is_a?(Symbol) ? 
+          ActiveResource::Formats[mime_type_reference_or_format] : mime_type_reference_or_format
+
+        write_inheritable_attribute("format", format)
+        connection.format = format
+      end
+      
+      # Returns the current format, default is ActiveResource::Formats::XmlFormat
+      def format # :nodoc:
+        read_inheritable_attribute("format") || ActiveResource::Formats[:xml]
+      end
+
       # An instance of ActiveResource::Connection that is the base connection to the remote service.
       # The +refresh+ parameter toggles whether or not the connection is refreshed at every request
       # or not (defaults to +false+).
       def connection(refresh = false)
-        if defined?(@connection) or superclass == Object
-          @connection = Connection.new(site) if refresh || @connection.nil?
+        if defined?(@connection) || superclass == Object
+          @connection = Connection.new(site, format) if refresh || @connection.nil?
           @connection
         else
           superclass.connection
@@ -252,7 +274,7 @@ module ActiveResource
       #
       def element_path(id, prefix_options = {}, query_options = nil)
         prefix_options, query_options = split_options(prefix_options) if query_options.nil?
-        "#{prefix(prefix_options)}#{collection_name}/#{id}.xml#{query_string(query_options)}"
+        "#{prefix(prefix_options)}#{collection_name}/#{id}.#{format.extension}#{query_string(query_options)}"
       end
 
       # Gets the collection path for the REST resources.  If the +query_options+ parameter is omitted, Rails
@@ -278,7 +300,7 @@ module ActiveResource
       #
       def collection_path(prefix_options = {}, query_options = nil)
         prefix_options, query_options = split_options(prefix_options) if query_options.nil?
-        "#{prefix(prefix_options)}#{collection_name}.xml#{query_string(query_options)}"
+        "#{prefix(prefix_options)}#{collection_name}.#{format.extension}#{query_string(query_options)}"
       end
 
       alias_method :set_primary_key, :primary_key=  #:nodoc:
@@ -781,7 +803,7 @@ module ActiveResource
       
       def load_attributes_from_response(response)
         if response['Content-size'] != "0" && response.body.strip.size > 0
-          load(connection.xml_from_response(response))
+          load(self.class.format.decode(response.body))
         end
       end
 

activeresource/lib/active_resource/connection.rb

@@ -47,23 +47,20 @@ module ActiveResource
   # services.
   class Connection
     attr_reader :site
+    attr_accessor :format
 
     class << self
       def requests
         @@requests ||= []
       end
-      
-      def default_header
-        class << self ; attr_reader :default_header end
-        @default_header = { 'Content-Type' => 'application/xml' }
-      end
     end
 
     # The +site+ parameter is required and will set the +site+
     # attribute to the URI for the remote resource service.
-    def initialize(site)
+    def initialize(site, format = ActiveResource::Formats[:xml])
       raise ArgumentError, 'Missing site URI' unless site
       self.site = site
+      self.format = format
     end
 
     # Set URI for remote service.
@@ -74,7 +71,7 @@ module ActiveResource
     # Execute a GET request.
     # Used to get (find) resources.
     def get(path, headers = {})
-      xml_from_response(request(:get, path, build_request_headers(headers)))
+      format.decode(request(:get, path, build_request_headers(headers)).body)
     end
 
     # Execute a DELETE request (see HTTP protocol documentation if unfamiliar).
@@ -95,9 +92,6 @@ module ActiveResource
       request(:post, path, body.to_s, build_request_headers(headers))
     end
 
-    def xml_from_response(response)
-      from_xml_data(Hash.from_xml(response.body))
-    end
 
     private
       # Makes request to remote service.
@@ -144,10 +138,14 @@ module ActiveResource
 
         @http
       end
+
+      def default_header
+        @default_header ||= { 'Content-Type' => format.mime_type }
+      end
       
       # Builds headers for request to remote service.
       def build_request_headers(headers)
-        authorization_header.update(self.class.default_header).update(headers)
+        authorization_header.update(default_header).update(headers)
       end
       
       # Sets authorization header; authentication information is pulled from credentials provided with site URI.
@@ -158,15 +156,5 @@ module ActiveResource
       def logger #:nodoc:
         ActiveResource::Base.logger
       end
-
-      # Manipulate from_xml Hash, because xml_simple is not exactly what we
-      # want for ActiveResource.
-      def from_xml_data(data)
-        if data.is_a?(Hash) && data.keys.size == 1
-          data.values.first
-        else
-          data
-        end
-      end
   end
 end

activeresource/lib/active_resource/formats.rb

@@ -0,0 +1,14 @@
+module ActiveResource
+  module Formats
+    # Lookup the format class from a mime type reference symbol. Example:
+    #
+    #   ActiveResource::Formats[:xml]  # => ActiveResource::Formats::XmlFormat
+    #   ActiveResource::Formats[:json] # => ActiveResource::Formats::JsonFormat
+    def self.[](mime_type_reference)
+      ActiveResource::Formats.const_get(mime_type_reference.to_s.camelize + "Format")
+    end
+  end
+end
+
+require 'active_resource/formats/xml_format'
+require 'active_resource/formats/json_format'

activeresource/lib/active_resource/formats/json_format.rb

@@ -0,0 +1,23 @@
+module ActiveResource
+  module Formats
+    module JsonFormat
+      extend self
+      
+      def extension
+        "json"
+      end
+      
+      def mime_type
+        "application/json"
+      end
+      
+      def encode(hash)
+        hash.to_json
+      end
+      
+      def decode(json)
+        ActiveSupport::JSON.decode(json)
+      end
+    end
+  end
+end

activeresource/lib/active_resource/formats/xml_format.rb

@@ -0,0 +1,34 @@
+module ActiveResource
+  module Formats
+    module XmlFormat
+      extend self
+      
+      def extension
+        "xml"
+      end
+      
+      def mime_type
+        "application/xml"
+      end
+      
+      def encode(hash)
+        hash.to_xml
+      end
+      
+      def decode(xml)
+        from_xml_data(Hash.from_xml(xml))
+      end
+      
+      private
+        # Manipulate from_xml Hash, because xml_simple is not exactly what we
+        # want for ActiveResource.
+        def from_xml_data(data)
+          if data.is_a?(Hash) && data.keys.size == 1
+            data.values.first
+          else
+            data
+          end
+        end      
+    end
+  end
+end

activeresource/lib/active_resource/http_mock.rb

@@ -32,7 +32,12 @@ module ActiveResource
         pairs.each do |(path, response)|
           responses[path] = response
         end
-        yield Responder.new(responses) if block_given?
+
+        if block_given?
+          yield Responder.new(responses) 
+        else
+          Responder.new(responses)
+        end
       end
 
       def reset!

activeresource/test/format_test.rb

@@ -0,0 +1,42 @@
+require "#{File.dirname(__FILE__)}/abstract_unit"
+require "fixtures/person"
+
+class FormatTest < Test::Unit::TestCase
+  def setup
+    @matz  = { :id => 1, :name => 'Matz' }
+    @david = { :id => 2, :name => 'David' }
+    
+    @programmers = [ @matz, @david ]
+  end
+  
+  def test_formats_on_single_element
+    for format in [ :json, :xml ]
+      using_format(Person, format) do
+        ActiveResource::HttpMock.respond_to.get "/people/1.#{format}", {}, ActiveResource::Formats[format].encode(@david)
+        assert_equal @david[:name], Person.find(1).name
+      end
+    end
+  end
+
+  def test_formats_on_collection
+    for format in [ :json, :xml ]
+      using_format(Person, format) do
+        ActiveResource::HttpMock.respond_to.get "/people.#{format}", {}, ActiveResource::Formats[format].encode(@programmers)
+        remote_programmers = Person.find(:all)
+        assert_equal 2, remote_programmers.size
+        assert remote_programmers.select { |p| p.name == 'David' }
+      end
+    end
+  end
+
+  
+  private
+    def using_format(klass, mime_type_reference)
+      previous_format = klass.format
+      klass.format = mime_type_reference
+
+      yield
+    ensure
+      klass.format = previous_format
+    end
+end