Allow references for responses fixes westfieldlabs#84

lib/apivore/swagger.rb

@@ -34,11 +34,16 @@ def each_response(&block)
             raise "No responses found in swagger for path '#{path}', " \
               "method #{verb}: #{method_data.inspect}"
           end
+
           method_data.responses.each do |response_code, response_data|
-            schema_location = nil
-            if response_data.schema
-              schema_location = Fragment.new ['#', 'paths', path, verb, 'responses', response_code, 'schema']
-            end
+            schema_location =
+              case
+              when response_data.schema
+                Fragment.new(['#', 'paths', path, verb, 'responses', response_code, 'schema'])
+              when (ref = response_data['$ref'])
+                Fragment.new(ref.split('/'))
+              end
+
             block.call(path, verb, response_code, schema_location)
           end
         end

spec/apivore_spec.rb

@@ -31,7 +31,8 @@
           ["/services/{id}.json", "get", "200", ['#', 'paths', '/services/{id}.json', 'get', 'responses', '200', 'schema']],
           ["/services/{id}.json", "put", "204", nil],
           ["/services/{id}.json", "delete", "204", nil],
-          ["/services/{id}.json", "patch", "204", nil]
+          ["/services/{id}.json", "patch", "204", nil],
+          ["/services/{id}/with_response_definition.json", "get", "200", ['#', 'responses', 'sample_response']]
         )
       end
     end

spec/data/01_sample2.0.json

@@ -93,6 +93,17 @@
           }
         }
       }
+    },
+    "/services/{id}/with_response_definition.json": {
+      "get": {
+        "description": "Returns a service.",
+        "operationId": "Services#show",
+        "responses": {
+          "200": {
+            "$ref": "#/responses/sample_response"
+          }
+        }
+      }
     }
   },
   "definitions": {
@@ -110,5 +121,13 @@
         }
       }
     }
+  },
+  "responses": {
+    "sample_response": {
+      "description": "Sample response",
+      "schema": {
+        "$ref": "#/definitions/service"
+      }
+    }
   }
 }

spec/fixtures/application.rb

@@ -44,6 +44,8 @@ def call(env)
         respond_with 204
       when "PATCH /api/services/1.json"
         respond_with 204
+      when "GET /api/services/1/with_response_definition.json"
+        respond_with 200
       else
         if test_swagger_files.include?(path)
           respond_with 200, File.read(File.expand_path("../../data#{path}", __FILE__))

spec/request_spec.rb

@@ -38,6 +38,12 @@
         :patch, "/services/{id}.json", 204, {'id' => 1}
       )
     end
+
+    it do
+      expect(subject).to validate(
+        :get, "/services/{id}/with_response_definition.json", 200, {'id' => 1}
+      )
+    end
   end
 
   context 'and' do