Adding http_requests scenario

This patch adds http_requests scenario which takes a url and an
optional response code and returns the response code of the url
comparing it with expected response

bp http-based-benchmarking

Change-Id: I35373616a266f6bb6410df8afdb23a9229643812

doc/samples/tasks/scenarios/requests/check_response.json

@@ -0,0 +1,15 @@
+{
+    "Requests.check_response": [
+        {
+            "args": {
+                "url": "http://www.google.com",
+                "response": 302
+            },
+            "runner": {
+                "type": "constant",
+                "times": 20,
+                "concurrency": 5
+            },
+        }
+    ]
+}

doc/samples/tasks/scenarios/requests/check_response.yaml

@@ -0,0 +1,10 @@
+---
+  Requests.check_response:
+    -
+      args:
+          url: "http://www.google.com"
+          response: 302
+      runner:
+        type: "constant"
+        times: 20
+        concurrency: 5

rally-scenarios/rally.yaml

@@ -846,3 +846,13 @@
           users_per_tenant: 1
       sla:
         max_failure_percent: 0
+
+  Requests.check_response:
+    -
+      args:
+          url: "http://www.google.com"
+          response: 302
+      runner:
+        type: "constant"
+        times: 10
+        concurrency: 5

rally/benchmark/scenarios/requests/http_requests.py

@@ -0,0 +1,40 @@
+#    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 requests
+
+from rally.benchmark.scenarios import base as scenario_base
+from rally import exceptions
+from rally.openstack.common.gettextutils import _
+
+
+class WrongStatusException(exceptions.RallyException):
+    msg_fmt = _("Requests scenario exception: '%(message)s'")
+
+
+class Requests(scenario_base.Scenario):
+    """This class should contain all the http_request scenarios."""
+
+    @scenario_base.scenario()
+    def check_response(self, url, response=None):
+        """Standard way to benchmark web services.
+
+        This benchmark is used to GET a URL and check it with expected
+        Response.
+
+        :param url: URL to be fetched
+        :param response: Expected Response Code
+        """
+        resp = requests.head(url)
+        if response and response != resp.status_code:
+            error = "Expected Response and Actual Response not equal"
+            raise WrongStatusException(error)

tests/benchmark/scenarios/requests/test_http_requests.py

@@ -0,0 +1,31 @@
+#    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 mock
+
+from rally.benchmark.scenarios.requests import http_requests
+from tests import test
+
+SCN = "rally.benchmark.scenarios"
+
+
+class RequestsTestCase(test.TestCase):
+
+    @mock.patch("%s.requests.http_requests.requests" % SCN)
+    def test_check_response(self, mock_requests):
+        mock_requests.head(mock.MagicMock()).status_code = 200
+        Requests = http_requests.Requests()
+
+        self.assertRaises(http_requests.WrongStatusException,
+                          Requests.check_response, url="sample_url",
+                          response=302)