Use HEAD instead of GET inside exists? Closes #11062 [bscofield]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8827 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 15 insertions, 3 deletions

diff --git a/activeresource/lib/active_resource/base.rb b/activeresource/lib/active_resource/base.rb
index eea6259a64..97baa46682 100644
--- a/activeresource/lib/active_resource/base.rb
+++ b/activeresource/lib/active_resource/base.rb
@@ -436,7 +436,13 @@ module ActiveResource
       #   Note.exists(1349)
       #   # => false
       def exists?(id, options = {})
-        id && !find_single(id, options).nil?
+        if id
+          prefix_options, query_options = split_options(options[:params])
+          path = element_path(id, prefix_options, query_options)
+          response = connection.head(path, headers)
+          response.code == 200
+        end
+        # id && !find_single(id, options).nil?
       rescue ActiveResource::ResourceNotFound
         false
       end
diff --git a/activeresource/lib/active_resource/connection.rb b/activeresource/lib/active_resource/connection.rb
index 2bf83b1615..e4e6da50c9 100644
--- a/activeresource/lib/active_resource/connection.rb
+++ b/activeresource/lib/active_resource/connection.rb
@@ -101,6 +101,12 @@ module ActiveResource
       request(:post, path, body.to_s, build_request_headers(headers))
     end
 
+    # Execute a HEAD request.
+    # Used to ...
+    def head(path, headers= {})
+      request(:head, path, build_request_headers(headers))
+    end
+
 
     private
       # Makes request to remote service.
diff --git a/activeresource/lib/active_resource/http_mock.rb b/activeresource/lib/active_resource/http_mock.rb
index d70364c5eb..d1c1412575 100644
--- a/activeresource/lib/active_resource/http_mock.rb
+++ b/activeresource/lib/active_resource/http_mock.rb
@@ -9,7 +9,7 @@ module ActiveResource
         @responses = responses
       end
 
-      for method in [ :post, :put, :get, :delete ]
+      for method in [ :post, :put, :get, :delete, :head ]
         module_eval <<-EOE, __FILE__, __LINE__
           def #{method}(path, request_headers = {}, body = nil, status = 200, response_headers = {})
             @responses[Request.new(:#{method}, path, nil, request_headers)] = Response.new(body || "", status, response_headers)
@@ -56,7 +56,7 @@ module ActiveResource
       EOE
     end
 
-    for method in [ :get, :delete ]
+    for method in [ :get, :delete, :head ]
       module_eval <<-EOE, __FILE__, __LINE__
         def #{method}(path, headers)
           request = ActiveResource::Request.new(:#{method}, path, nil, headers)