1 files changed, 68 insertions, 0 deletions
diff --git a/synapse/rest/client/capabilities.py b/synapse/rest/client/capabilities.py
new file mode 100644
index 0000000000..88e3aac797
--- /dev/null
+++ b/synapse/rest/client/capabilities.py
@@ -0,0 +1,68 @@
+# Copyright 2019 New Vector
+#
+# 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 logging
+from typing import TYPE_CHECKING, Tuple
+
+from synapse.api.room_versions import KNOWN_ROOM_VERSIONS, MSC3244_CAPABILITIES
+from synapse.http.servlet import RestServlet
+from synapse.http.site import SynapseRequest
+from synapse.types import JsonDict
+
+from ._base import client_patterns
+
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
+logger = logging.getLogger(__name__)
+
+
+class CapabilitiesRestServlet(RestServlet):
+    """End point to expose the capabilities of the server."""
+
+    PATTERNS = client_patterns("/capabilities$")
+
+    def __init__(self, hs: "HomeServer"):
+        super().__init__()
+        self.hs = hs
+        self.config = hs.config
+        self.auth = hs.get_auth()
+        self.auth_handler = hs.get_auth_handler()
+
+    async def on_GET(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
+        await self.auth.get_user_by_req(request, allow_guest=True)
+        change_password = self.auth_handler.can_change_password()
+
+        response = {
+            "capabilities": {
+                "m.room_versions": {
+                    "default": self.config.default_room_version.identifier,
+                    "available": {
+                        v.identifier: v.disposition
+                        for v in KNOWN_ROOM_VERSIONS.values()
+                    },
+                },
+                "m.change_password": {"enabled": change_password},
+            }
+        }
+
+        if self.config.experimental.msc3244_enabled:
+            response["capabilities"]["m.room_versions"][
+                "org.matrix.msc3244.room_capabilities"
+            ] = MSC3244_CAPABILITIES
+
+        return 200, response
+
+
+def register_servlets(hs: "HomeServer", http_server):
+    CapabilitiesRestServlet(hs).register(http_server)