Flatten the synapse.rest.client package (#10600)

1 files changed, 381 insertions, 0 deletions

diff --git a/synapse/rest/client/relations.py b/synapse/rest/client/relations.py
new file mode 100644
index 0000000000..0821cd285f
--- /dev/null
+++ b/synapse/rest/client/relations.py
@@ -0,0 +1,381 @@
+# Copyright 2019 New Vector 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.
+
+"""This class implements the proposed relation APIs from MSC 1849.
+
+Since the MSC has not been approved all APIs here are unstable and may change at
+any time to reflect changes in the MSC.
+"""
+
+import logging
+
+from synapse.api.constants import EventTypes, RelationTypes
+from synapse.api.errors import ShadowBanError, SynapseError
+from synapse.http.servlet import (
+    RestServlet,
+    parse_integer,
+    parse_json_object_from_request,
+    parse_string,
+)
+from synapse.rest.client.transactions import HttpTransactionCache
+from synapse.storage.relations import (
+    AggregationPaginationToken,
+    PaginationChunk,
+    RelationPaginationToken,
+)
+from synapse.util.stringutils import random_string
+
+from ._base import client_patterns
+
+logger = logging.getLogger(__name__)
+
+
+class RelationSendServlet(RestServlet):
+    """Helper API for sending events that have relation data.
+
+    Example API shape to send a 👍 reaction to a room:
+
+        POST /rooms/!foo/send_relation/$bar/m.annotation/m.reaction?key=%F0%9F%91%8D
+        {}
+
+        {
+            "event_id": "$foobar"
+        }
+    """
+
+    PATTERN = (
+        "/rooms/(?P<room_id>[^/]*)/send_relation"
+        "/(?P<parent_id>[^/]*)/(?P<relation_type>[^/]*)/(?P<event_type>[^/]*)"
+    )
+
+    def __init__(self, hs):
+        super().__init__()
+        self.auth = hs.get_auth()
+        self.event_creation_handler = hs.get_event_creation_handler()
+        self.txns = HttpTransactionCache(hs)
+
+    def register(self, http_server):
+        http_server.register_paths(
+            "POST",
+            client_patterns(self.PATTERN + "$", releases=()),
+            self.on_PUT_or_POST,
+            self.__class__.__name__,
+        )
+        http_server.register_paths(
+            "PUT",
+            client_patterns(self.PATTERN + "/(?P<txn_id>[^/]*)$", releases=()),
+            self.on_PUT,
+            self.__class__.__name__,
+        )
+
+    def on_PUT(self, request, *args, **kwargs):
+        return self.txns.fetch_or_execute_request(
+            request, self.on_PUT_or_POST, request, *args, **kwargs
+        )
+
+    async def on_PUT_or_POST(
+        self, request, room_id, parent_id, relation_type, event_type, txn_id=None
+    ):
+        requester = await self.auth.get_user_by_req(request, allow_guest=True)
+
+        if event_type == EventTypes.Member:
+            # Add relations to a membership is meaningless, so we just deny it
+            # at the CS API rather than trying to handle it correctly.
+            raise SynapseError(400, "Cannot send member events with relations")
+
+        content = parse_json_object_from_request(request)
+
+        aggregation_key = parse_string(request, "key", encoding="utf-8")
+
+        content["m.relates_to"] = {
+            "event_id": parent_id,
+            "key": aggregation_key,
+            "rel_type": relation_type,
+        }
+
+        event_dict = {
+            "type": event_type,
+            "content": content,
+            "room_id": room_id,
+            "sender": requester.user.to_string(),
+        }
+
+        try:
+            (
+                event,
+                _,
+            ) = await self.event_creation_handler.create_and_send_nonmember_event(
+                requester, event_dict=event_dict, txn_id=txn_id
+            )
+            event_id = event.event_id
+        except ShadowBanError:
+            event_id = "$" + random_string(43)
+
+        return 200, {"event_id": event_id}
+
+
+class RelationPaginationServlet(RestServlet):
+    """API to paginate relations on an event by topological ordering, optionally
+    filtered by relation type and event type.
+    """
+
+    PATTERNS = client_patterns(
+        "/rooms/(?P<room_id>[^/]*)/relations/(?P<parent_id>[^/]*)"
+        "(/(?P<relation_type>[^/]*)(/(?P<event_type>[^/]*))?)?$",
+        releases=(),
+    )
+
+    def __init__(self, hs):
+        super().__init__()
+        self.auth = hs.get_auth()
+        self.store = hs.get_datastore()
+        self.clock = hs.get_clock()
+        self._event_serializer = hs.get_event_client_serializer()
+        self.event_handler = hs.get_event_handler()
+
+    async def on_GET(
+        self, request, room_id, parent_id, relation_type=None, event_type=None
+    ):
+        requester = await self.auth.get_user_by_req(request, allow_guest=True)
+
+        await self.auth.check_user_in_room_or_world_readable(
+            room_id, requester.user.to_string(), allow_departed_users=True
+        )
+
+        # This gets the original event and checks that a) the event exists and
+        # b) the user is allowed to view it.
+        event = await self.event_handler.get_event(requester.user, room_id, parent_id)
+
+        limit = parse_integer(request, "limit", default=5)
+        from_token_str = parse_string(request, "from")
+        to_token_str = parse_string(request, "to")
+
+        if event.internal_metadata.is_redacted():
+            # If the event is redacted, return an empty list of relations
+            pagination_chunk = PaginationChunk(chunk=[])
+        else:
+            # Return the relations
+            from_token = None
+            if from_token_str:
+                from_token = RelationPaginationToken.from_string(from_token_str)
+
+            to_token = None
+            if to_token_str:
+                to_token = RelationPaginationToken.from_string(to_token_str)
+
+            pagination_chunk = await self.store.get_relations_for_event(
+                event_id=parent_id,
+                relation_type=relation_type,
+                event_type=event_type,
+                limit=limit,
+                from_token=from_token,
+                to_token=to_token,
+            )
+
+        events = await self.store.get_events_as_list(
+            [c["event_id"] for c in pagination_chunk.chunk]
+        )
+
+        now = self.clock.time_msec()
+        # We set bundle_aggregations to False when retrieving the original
+        # event because we want the content before relations were applied to
+        # it.
+        original_event = await self._event_serializer.serialize_event(
+            event, now, bundle_aggregations=False
+        )
+        # Similarly, we don't allow relations to be applied to relations, so we
+        # return the original relations without any aggregations on top of them
+        # here.
+        events = await self._event_serializer.serialize_events(
+            events, now, bundle_aggregations=False
+        )
+
+        return_value = pagination_chunk.to_dict()
+        return_value["chunk"] = events
+        return_value["original_event"] = original_event
+
+        return 200, return_value
+
+
+class RelationAggregationPaginationServlet(RestServlet):
+    """API to paginate aggregation groups of relations, e.g. paginate the
+    types and counts of the reactions on the events.
+
+    Example request and response:
+
+        GET /rooms/{room_id}/aggregations/{parent_id}
+
+        {
+            chunk: [
+                {
+                    "type": "m.reaction",
+                    "key": "👍",
+                    "count": 3
+                }
+            ]
+        }
+    """
+
+    PATTERNS = client_patterns(
+        "/rooms/(?P<room_id>[^/]*)/aggregations/(?P<parent_id>[^/]*)"
+        "(/(?P<relation_type>[^/]*)(/(?P<event_type>[^/]*))?)?$",
+        releases=(),
+    )
+
+    def __init__(self, hs):
+        super().__init__()
+        self.auth = hs.get_auth()
+        self.store = hs.get_datastore()
+        self.event_handler = hs.get_event_handler()
+
+    async def on_GET(
+        self, request, room_id, parent_id, relation_type=None, event_type=None
+    ):
+        requester = await self.auth.get_user_by_req(request, allow_guest=True)
+
+        await self.auth.check_user_in_room_or_world_readable(
+            room_id,
+            requester.user.to_string(),
+            allow_departed_users=True,
+        )
+
+        # This checks that a) the event exists and b) the user is allowed to
+        # view it.
+        event = await self.event_handler.get_event(requester.user, room_id, parent_id)
+
+        if relation_type not in (RelationTypes.ANNOTATION, None):
+            raise SynapseError(400, "Relation type must be 'annotation'")
+
+        limit = parse_integer(request, "limit", default=5)
+        from_token_str = parse_string(request, "from")
+        to_token_str = parse_string(request, "to")
+
+        if event.internal_metadata.is_redacted():
+            # If the event is redacted, return an empty list of relations
+            pagination_chunk = PaginationChunk(chunk=[])
+        else:
+            # Return the relations
+            from_token = None
+            if from_token_str:
+                from_token = AggregationPaginationToken.from_string(from_token_str)
+
+            to_token = None
+            if to_token_str:
+                to_token = AggregationPaginationToken.from_string(to_token_str)
+
+            pagination_chunk = await self.store.get_aggregation_groups_for_event(
+                event_id=parent_id,
+                event_type=event_type,
+                limit=limit,
+                from_token=from_token,
+                to_token=to_token,
+            )
+
+        return 200, pagination_chunk.to_dict()
+
+
+class RelationAggregationGroupPaginationServlet(RestServlet):
+    """API to paginate within an aggregation group of relations, e.g. paginate
+    all the 👍 reactions on an event.
+
+    Example request and response:
+
+        GET /rooms/{room_id}/aggregations/{parent_id}/m.annotation/m.reaction/👍
+
+        {
+            chunk: [
+                {
+                    "type": "m.reaction",
+                    "content": {
+                        "m.relates_to": {
+                            "rel_type": "m.annotation",
+                            "key": "👍"
+                        }
+                    }
+                },
+                ...
+            ]
+        }
+    """
+
+    PATTERNS = client_patterns(
+        "/rooms/(?P<room_id>[^/]*)/aggregations/(?P<parent_id>[^/]*)"
+        "/(?P<relation_type>[^/]*)/(?P<event_type>[^/]*)/(?P<key>[^/]*)$",
+        releases=(),
+    )
+
+    def __init__(self, hs):
+        super().__init__()
+        self.auth = hs.get_auth()
+        self.store = hs.get_datastore()
+        self.clock = hs.get_clock()
+        self._event_serializer = hs.get_event_client_serializer()
+        self.event_handler = hs.get_event_handler()
+
+    async def on_GET(self, request, room_id, parent_id, relation_type, event_type, key):
+        requester = await self.auth.get_user_by_req(request, allow_guest=True)
+
+        await self.auth.check_user_in_room_or_world_readable(
+            room_id,
+            requester.user.to_string(),
+            allow_departed_users=True,
+        )
+
+        # This checks that a) the event exists and b) the user is allowed to
+        # view it.
+        await self.event_handler.get_event(requester.user, room_id, parent_id)
+
+        if relation_type != RelationTypes.ANNOTATION:
+            raise SynapseError(400, "Relation type must be 'annotation'")
+
+        limit = parse_integer(request, "limit", default=5)
+        from_token_str = parse_string(request, "from")
+        to_token_str = parse_string(request, "to")
+
+        from_token = None
+        if from_token_str:
+            from_token = RelationPaginationToken.from_string(from_token_str)
+
+        to_token = None
+        if to_token_str:
+            to_token = RelationPaginationToken.from_string(to_token_str)
+
+        result = await self.store.get_relations_for_event(
+            event_id=parent_id,
+            relation_type=relation_type,
+            event_type=event_type,
+            aggregation_key=key,
+            limit=limit,
+            from_token=from_token,
+            to_token=to_token,
+        )
+
+        events = await self.store.get_events_as_list(
+            [c["event_id"] for c in result.chunk]
+        )
+
+        now = self.clock.time_msec()
+        events = await self._event_serializer.serialize_events(events, now)
+
+        return_value = result.to_dict()
+        return_value["chunk"] = events
+
+        return 200, return_value
+
+
+def register_servlets(hs, http_server):
+    RelationSendServlet(hs).register(http_server)
+    RelationPaginationServlet(hs).register(http_server)
+    RelationAggregationPaginationServlet(hs).register(http_server)
+    RelationAggregationGroupPaginationServlet(hs).register(http_server)