Add response schema validation (only when in TESTING mode) and add one schema. More will be added in a followup CL

endpoints/api/__init__.py

@@ -1,6 +1,7 @@
 import logging
 import json
 
+from app import app
 from flask import Blueprint, request, make_response, jsonify
 from flask.ext.restful import Resource, abort, Api, reqparse
 from flask.ext.restful.utils.cors import crossdomain
@@ -52,6 +53,11 @@ class InvalidRequest(ApiException):
     ApiException.__init__(self, 'invalid_request', 400, error_description, payload)
 
 
+class InvalidResponse(ApiException):
+  def __init__(self, error_description, payload=None):
+    ApiException.__init__(self, 'invalid_response', 500, error_description, payload)
+
+
 class InvalidToken(ApiException):
   def __init__(self, error_description, payload=None):
     ApiException.__init__(self, 'invalid_token', 401, error_description, payload)
@@ -286,6 +292,25 @@ def validate_json_request(schema_name):
   return wrapper
 
 
+def define_json_response(schema_name):
+  def wrapper(func):
+    @add_method_metadata('response_schema', schema_name)
+    @wraps(func)
+    def wrapped(self, *args, **kwargs):
+      schema = self.schemas[schema_name]
+      try:
+        resp = func(self, *args, **kwargs)
+
+        if app.config['TESTING']:
+          validate(resp, schema)
+
+        return resp
+      except ValidationError as ex:
+        raise InvalidResponse(ex.message)
+    return wrapped
+  return wrapper
+
+
 def request_error(exception=None, **kwargs):
   data = kwargs.copy()
   message = 'Request error.'