GET /devices endpoint

implement a GET /devices endpoint which lists all of the user's devices.

It also returns the last IP where we saw that device, so there is some dancing
to fish that out of the user_ips table.

tests/storage/test_devices.py

@@ -0,0 +1,71 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# 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.
+
+from twisted.internet import defer
+
+import synapse.server
+import synapse.types
+import tests.unittest
+import tests.utils
+
+
+class DeviceStoreTestCase(tests.unittest.TestCase):
+    def __init__(self, *args, **kwargs):
+        super(DeviceStoreTestCase, self).__init__(*args, **kwargs)
+        self.store = None  # type: synapse.storage.DataStore
+
+    @defer.inlineCallbacks
+    def setUp(self):
+        hs = yield tests.utils.setup_test_homeserver()
+
+        self.store = hs.get_datastore()
+
+    @defer.inlineCallbacks
+    def test_store_new_device(self):
+        yield self.store.store_device(
+            "user_id", "device_id", "display_name"
+        )
+
+        res = yield self.store.get_device("user_id", "device_id")
+        self.assertDictContainsSubset({
+            "user_id": "user_id",
+            "device_id": "device_id",
+            "display_name": "display_name",
+        }, res)
+
+    @defer.inlineCallbacks
+    def test_get_devices_by_user(self):
+        yield self.store.store_device(
+            "user_id", "device1", "display_name 1"
+        )
+        yield self.store.store_device(
+            "user_id", "device2", "display_name 2"
+        )
+        yield self.store.store_device(
+            "user_id2", "device3", "display_name 3"
+        )
+
+        res = yield self.store.get_devices_by_user("user_id")
+        self.assertEqual(2, len(res.keys()))
+        self.assertDictContainsSubset({
+            "user_id": "user_id",
+            "device_id": "device1",
+            "display_name": "display_name 1",
+        }, res["device1"])
+        self.assertDictContainsSubset({
+            "user_id": "user_id",
+            "device_id": "device2",
+            "display_name": "display_name 2",
+        }, res["device2"])