Add config.default_method_for_update to support PATCH

PATCH is the correct HTML verb to map to the #update action. The
semantics for PATCH allows for partial updates, whereas PUT requires a
complete replacement.

Changes:
* adds config.default_method_for_update you can set to :patch
* optionally use PATCH instead of PUT in resource routes and forms
* adds the #patch verb to routes to detect PATCH requests
* adds #patch? to Request
* changes documentation and comments to indicate support for PATCH

This change maintains complete backwards compatibility by keeping :put
as the default for config.default_method_for_update.

5 files changed, 32 insertions, 13 deletions

diff --git a/activeresource/lib/active_resource/connection.rb b/activeresource/lib/active_resource/connection.rb
index 46060b6f74..8a8dc3146d 100644
--- a/activeresource/lib/active_resource/connection.rb
+++ b/activeresource/lib/active_resource/connection.rb
@@ -15,6 +15,7 @@ module ActiveResource
     HTTP_FORMAT_HEADER_NAMES = {  :get => 'Accept',
       :put => 'Content-Type',
       :post => 'Content-Type',
+      :patch => 'Content-Type',
       :delete => 'Accept',
       :head => 'Accept'
     }
@@ -86,6 +87,12 @@ module ActiveResource
       with_auth { request(:delete, path, build_request_headers(headers, :delete, self.site.merge(path))) }
     end
 
+    # Executes a PATCH request (see HTTP protocol documentation if unfamiliar).
+    # Used to update resources.
+    def patch(path, body = '', headers = {})
+      with_auth { request(:patch, path, body.to_s, build_request_headers(headers, :patch, self.site.merge(path))) }
+    end
+
     # Executes a PUT request (see HTTP protocol documentation if unfamiliar).
     # Used to update resources.
     def put(path, body = '', headers = {})
diff --git a/activeresource/lib/active_resource/custom_methods.rb b/activeresource/lib/active_resource/custom_methods.rb
index a0eb28ed13..095dcd2a8e 100644
--- a/activeresource/lib/active_resource/custom_methods.rb
+++ b/activeresource/lib/active_resource/custom_methods.rb
@@ -11,10 +11,10 @@ module ActiveResource
   #
   #  This route set creates routes for the following HTTP requests:
   #
-  #    POST    /people/new/register.json # PeopleController.register
-  #    PUT     /people/1/promote.json    # PeopleController.promote with :id => 1
-  #    DELETE  /people/1/deactivate.json # PeopleController.deactivate with :id => 1
-  #    GET     /people/active.json       # PeopleController.active
+  #    POST      /people/new/register.json # PeopleController.register
+  #    PUT/PATCH /people/1/promote.json    # PeopleController.promote with :id => 1
+  #    DELETE    /people/1/deactivate.json # PeopleController.deactivate with :id => 1
+  #    GET       /people/active.json       # PeopleController.active
   #
   # Using this module, Active Resource can use these custom REST methods just like the
   # standard methods.
@@ -63,6 +63,10 @@ module ActiveResource
           connection.post(custom_method_collection_url(custom_method_name, options), body, headers)
         end
 
+        def patch(custom_method_name, options = {}, body = '')
+          connection.patch(custom_method_collection_url(custom_method_name, options), body, headers)
+        end
+
         def put(custom_method_name, options = {}, body = '')
           connection.put(custom_method_collection_url(custom_method_name, options), body, headers)
         end
@@ -98,6 +102,10 @@ module ActiveResource
       end
     end
 
+    def patch(method_name, options = {}, body = '')
+      connection.patch(custom_method_element_url(method_name, options), body, self.class.headers)
+    end
+
     def put(method_name, options = {}, body = '')
       connection.put(custom_method_element_url(method_name, options), body, self.class.headers)
     end
diff --git a/activeresource/lib/active_resource/http_mock.rb b/activeresource/lib/active_resource/http_mock.rb
index 666b961f87..820b178d4b 100644
--- a/activeresource/lib/active_resource/http_mock.rb
+++ b/activeresource/lib/active_resource/http_mock.rb
@@ -15,7 +15,7 @@ module ActiveResource
   #
   #   mock.http_method(path, request_headers = {}, body = nil, status = 200, response_headers = {})
   #
-  # * <tt>http_method</tt> - The HTTP method to listen for. This can be +get+, +post+, +put+, +delete+ or
+  # * <tt>http_method</tt> - The HTTP method to listen for. This can be +get+, +post+, +patch+, +put+, +delete+ or
   #   +head+.
   # * <tt>path</tt> - A string, starting with a "/", defining the URI that is expected to be
   #   called.
@@ -55,7 +55,7 @@ module ActiveResource
         @responses = responses
       end
 
-      [ :post, :put, :get, :delete, :head ].each do |method|
+      [ :post, :put, :patch, :get, :delete, :head ].each do |method|
         # def post(path, request_headers = {}, body = nil, status = 200, response_headers = {})
         #   @responses[Request.new(:post, path, nil, request_headers)] = Response.new(body || "", status, response_headers)
         # end
@@ -217,7 +217,7 @@ module ActiveResource
     end
 
     # body?       methods
-    { true  => %w(post put),
+    { true  => %w(post patch put),
       false => %w(get delete head) }.each do |has_body, methods|
       methods.each do |method|
         # def post(path, body, headers)
diff --git a/activeresource/test/cases/format_test.rb b/activeresource/test/cases/format_test.rb
index 30342ecc74..315f9db1eb 100644
--- a/activeresource/test/cases/format_test.rb
+++ b/activeresource/test/cases/format_test.rb
@@ -11,11 +11,15 @@ class FormatTest < ActiveSupport::TestCase
   end
 
   def test_http_format_header_name
-    header_name = ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[:get]
-    assert_equal 'Accept', header_name
+    [:get, :head].each do |verb|
+      header_name = ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[verb]
+      assert_equal 'Accept', header_name
+    end
 
-    headers_names = [ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[:put], ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[:post]]
-    headers_names.each{ |name| assert_equal 'Content-Type', name }
+    [:patch, :put, :post].each do |verb|
+      header_name = ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES[verb]
+      assert_equal 'Content-Type', header_name
+    end
   end
 
   def test_formats_on_single_element
diff --git a/activeresource/test/cases/http_mock_test.rb b/activeresource/test/cases/http_mock_test.rb
index d2fd911314..d13d9258ce 100644
--- a/activeresource/test/cases/http_mock_test.rb
+++ b/activeresource/test/cases/http_mock_test.rb
@@ -8,7 +8,7 @@ class HttpMockTest < ActiveSupport::TestCase
 
   FORMAT_HEADER = ActiveResource::Connection::HTTP_FORMAT_HEADER_NAMES
 
-  [:post, :put, :get, :delete, :head].each do |method|
+  [:post, :patch, :put, :get, :delete, :head].each do |method|
     test "responds to simple #{method} request" do
       ActiveResource::HttpMock.respond_to do |mock|
         mock.send(method, "/people/1", { FORMAT_HEADER[method] => "application/json" }, "Response")
@@ -193,7 +193,7 @@ class HttpMockTest < ActiveSupport::TestCase
   end
 
   def request(method, path, headers = {}, body = nil)
-    if method.in?([:put, :post])
+    if method.in?([:patch, :put, :post])
       @http.send(method, path, body, headers)
     else
       @http.send(method, path, headers)