Do not attempt to JSON parse the body of a 204 response.

An HTTP 204 No Content response may have a Content-Type header even
though it has no content--this is not disallowed by the RFC. Update
Chef::REST to handle this case and not attempt to parse the (nil)
response.

2 files changed, 20 insertions, 1 deletions

diff --git a/chef/lib/chef/rest.rb b/chef/lib/chef/rest.rb
index 48ef218e87..14bff6a304 100644
--- a/chef/lib/chef/rest.rb
+++ b/chef/lib/chef/rest.rb
@@ -267,7 +267,11 @@ class Chef
 
           response_body = decompress_body(response)
 
-          if response.kind_of?(Net::HTTPSuccess)
+          # 204 is successful, Net::HTTP returns nil response body.
+          # Don't attempt to parse it.
+          if response.kind_of?(Net::HTTPNoContent)
+            response_body
+          elsif response.kind_of?(Net::HTTPSuccess)
             if response['content-type'] =~ /json/
               Chef::JSONCompat.from_json(response_body.chomp)
             else
diff --git a/chef/spec/unit/rest_spec.rb b/chef/spec/unit/rest_spec.rb
index f24ef1a08d..c3385df2c0 100644
--- a/chef/spec/unit/rest_spec.rb
+++ b/chef/spec/unit/rest_spec.rb
@@ -422,6 +422,21 @@ describe Chef::REST do
         @rest.api_request(:GET, @url).should == "ninja"
       end
 
+      it "returns nil when the response is a 204 and the content-type is JSON" do
+
+        @http_response = Net::HTTPNoContent.new("1.1", "204", "successful rest req")
+        @http_response.stub!(:read_body)
+        @http_response.stub!(:body).and_return(nil)
+        @http_response.add_field("Content-Length", "0")
+        @http_response.add_field("Content-Type", "application/json")
+
+        @http_client = Net::HTTP.new(@url.host, @url.port)
+        Net::HTTP.stub!(:new).and_return(@http_client)
+        @http_client.stub!(:request).and_yield(@http_response).and_return(@http_response)
+
+        @rest.api_request(:GET, @url).should be_nil
+      end
+
       it "should inflate the body as to an object if JSON is returned" do
         @http_response.add_field('content-type', "application/json")
         @http_response.stub!(:body).and_return('{"ohai2u":"json_api"}')