add support for getting status of individual changes

This expands the rest API for zuul for selecting a portion of the zuul
data.

The supported urls are:
 - /status: return a complex data structure that represents the entire
   queue / pipeline structure of the system
 - /status.json (backwards compatibility): same as /status
 - /status/change/X,Y: return status just for gerrit change X,Y

In the individual status case the changes are returned as a simple
array, and not in the pipeline structure.

Tests are added to demonstrate this working, as well as ensure 404 is
correctly returned when invalid urls are provided.

Co-Authored-By: Joshua Hesketh <joshua.hesketh@rackspace.com>

Change-Id: Ib8d80530cc99c222226f73046c17ab0bbf6e080b
diff --git a/tests/test_webapp.py b/tests/test_webapp.py
new file mode 100644
index 0000000..b127c51
--- /dev/null
+++ b/tests/test_webapp.py
@@ -0,0 +1,85 @@
+#!/usr/bin/env python
+
+# Copyright 2014 Hewlett-Packard Development Company, L.P.
+# Copyright 2014 Rackspace Australia
+#
+# 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
+import urllib2
+
+from tests.base import ZuulTestCase
+
+
+class TestWebapp(ZuulTestCase):
+
+    def _cleanup(self):
+        self.worker.hold_jobs_in_build = False
+        self.worker.release()
+        self.waitUntilSettled()
+
+    def setUp(self):
+        super(TestWebapp, self).setUp()
+        self.addCleanup(self._cleanup)
+        self.worker.hold_jobs_in_build = True
+        A = self.fake_gerrit.addFakeChange('org/project', 'master', 'A')
+        A.addApproval('CRVW', 2)
+        self.fake_gerrit.addEvent(A.addApproval('APRV', 1))
+        B = self.fake_gerrit.addFakeChange('org/project1', 'master', 'B')
+        B.addApproval('CRVW', 2)
+        self.fake_gerrit.addEvent(B.addApproval('APRV', 1))
+        self.waitUntilSettled()
+        self.port = self.webapp.server.socket.getsockname()[1]
+
+    def test_webapp_status(self):
+        "Test that we can filter to only certain changes in the webapp."
+
+        req = urllib2.Request(
+            "http://localhost:%s/status" % self.port)
+        f = urllib2.urlopen(req)
+        data = json.loads(f.read())
+
+        self.assertIn('pipelines', data)
+
+    def test_webapp_status_compat(self):
+        # testing compat with status.json
+        req = urllib2.Request(
+            "http://localhost:%s/status.json" % self.port)
+        f = urllib2.urlopen(req)
+        data = json.loads(f.read())
+
+        self.assertIn('pipelines', data)
+
+    def test_webapp_bad_url(self):
+        # do we 404 correctly
+        req = urllib2.Request(
+            "http://localhost:%s/status/foo" % self.port)
+        self.assertRaises(urllib2.HTTPError, urllib2.urlopen, req)
+
+    def test_webapp_find_change(self):
+        # can we filter by change id
+        req = urllib2.Request(
+            "http://localhost:%s/status/change/1,1" % self.port)
+        f = urllib2.urlopen(req)
+        data = json.loads(f.read())
+
+        self.assertEqual(1, len(data), data)
+        self.assertEqual("org/project", data[0]['project'])
+
+        req = urllib2.Request(
+            "http://localhost:%s/status/change/2,1" % self.port)
+        f = urllib2.urlopen(req)
+        data = json.loads(f.read())
+
+        self.assertEqual(1, len(data), data)
+        self.assertEqual("org/project1", data[0]['project'], data)