Pretty print json content in http response

Because all content of valence http response is jsonable object, use
flask.jsonify to pretty print it. The wrapper function
make_response() is added in to utils module.

Change-Id: I99cecb8a538182691936b8a42252feff6a5374d0
Closes-Bug: #1647888

valence/api/root.py

@@ -22,6 +22,7 @@ from flask_restful import Resource
 from valence.api import base
 from valence.api import link
 from valence.api import types
+from valence.common import utils
 from valence.redfish import redfish as rfs
 
 
@@ -87,7 +88,9 @@ class Root(Resource):
 
     def get(self):
         obj = RootBase.convert()
-        return json.loads(json.dumps(obj, default=lambda o: o.as_dict()))
+        return utils.make_response(
+            200,
+            json.loads(json.dumps(obj, default=lambda o: o.as_dict())))
 
 
 class PODMProxy(Resource):

valence/api/v1/version.py

@@ -20,6 +20,7 @@ from flask_restful import Resource
 from valence.api import base
 from valence.api import link
 from valence.api import types
+from valence.common import utils
 
 
 class MediaType(base.APIBase):
@@ -107,4 +108,6 @@ class V1(Resource):
 
     def get(self):
         vobj = V1Base.convert()
-        return json.loads(json.dumps(vobj, default=lambda o: o.as_dict()))
+        return utils.make_response(
+            200,
+            json.loads(json.dumps(vobj, default=lambda o: o.as_dict())))

valence/common/utils.py

@@ -1,16 +1,16 @@
-# Copyright 2016 Intel Corporation
+# Copyright (c) 2016 Intel, Inc.
 #
-# Licensed under the Apache License, Version 2.0 (the "License"); you may
-# not use this file except in compliance with the License. You may obtain
-# a copy of the License at
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
 #
-#      http://www.apache.org/licenses/LICENSE-2.0
+#         http://www.apache.org/licenses/LICENSE-2.0
 #
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
-# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
-# License for the specific language governing permissions and limitations
-# under the License.
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
 
 """This Module contains common function used across
    the project
@@ -20,6 +20,9 @@
 
 import logging
 
+from flask import jsonify
+import six
+
 LOG = logging.getLogger(__name__)
 
 
@@ -76,3 +79,30 @@ def match_conditions(json_content, filter_conditions):
             LOG.warn(" Filter string mismatch ")
     LOG.debug(" JSON CONTENT " + str(is_conditions_passed))
     return is_conditions_passed
+
+
+def make_response(status_code, content="", headers=None):
+    """Wrapper function to create flask http response.
+
+    :param json_content: content of http response, should be json object
+    :param status_code: status code of http response, set default to 200
+    :param headers: additional headers of http response, should be dict
+    :returns: return_type -- flask Response object
+    """
+
+    response = jsonify(content)
+
+    if isinstance(status_code, int):
+        response.status_code = status_code
+    else:
+        raise ValueError("Response status_code should be int object.")
+
+    # Set additional header for http response
+    if headers:
+        if isinstance(headers, dict):
+            for header, value in six.iteritems(headers):
+                response.headers[header] = value
+        else:
+            raise ValueError("Response headers should be dict object.")
+
+    return response

valence/tests/unit/common/test_utils.py

@@ -0,0 +1,55 @@
+# Copyright (c) 2016 Intel, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import json
+from unittest import TestCase
+
+from flask import Flask
+
+from valence.common import utils
+
+
+class TestMakeResponse(TestCase):
+
+    def setUp(self):
+        app = Flask(__name__)
+        self.app_context = app.test_request_context()
+        self.app_context.push()
+
+    def tearDown(self):
+        self.app_context.pop()
+
+    def test_make_response(self):
+        expect = {"key": "value"}
+        resp = utils.make_response(200, expect)
+        result = json.loads(resp.data.decode())
+        self.assertEqual(expect, result)
+        self.assertEqual(200, resp.status_code)
+
+    def test_make_response_with_wrong_status_code(self):
+        with self.assertRaises(ValueError):
+            utils.make_response(status_code="wrong_code")
+
+    def test_make_response_with_headers(self):
+        expect = {"key": "value"}
+        resp = utils.make_response(200, expect,
+                                   headers={"header": "header_value"})
+        result = json.loads(resp.data.decode())
+        self.assertEqual(expect, result)
+        self.assertEqual(200, resp.status_code)
+        self.assertEqual("header_value", resp.headers.get("header"))
+
+    def test_make_response_with_wrong_headers(self):
+        with self.assertRaises(ValueError):
+            utils.make_response(200, headers=("header", "header_value"))