More variable calculation for email notifs

Include name of the person we're sending to and add summary text at the top giving an overview of what's happened.

1 files changed, 145 insertions, 0 deletions

diff --git a/synapse/util/presentable_names.py b/synapse/util/presentable_names.py
new file mode 100644
index 0000000000..2ae01e453d
--- /dev/null
+++ b/synapse/util/presentable_names.py
@@ -0,0 +1,145 @@
+# -*- 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.
+
+import re
+
+# intentionally looser than what aliases we allow to be registered since
+# other HSes may allow aliases that we would not
+ALIAS_RE = re.compile(r"^#.*:.+$")
+
+ALL_ALONE = "Empty Room"
+
+
+def calculate_room_name(room_state, user_id, fallback_to_members=True):
+    # does it have a name?
+    if ("m.room.name", "") in room_state:
+        m_room_name = room_state[("m.room.name", "")]
+        if m_room_name.content and m_room_name.content["name"]:
+            return m_room_name.content["name"]
+
+    # does it have a canonical alias?
+    if ("m.room.canonical_alias", "") in room_state:
+        canon_alias = room_state[("m.room.canonical_alias", "")]
+        if (
+            canon_alias.content and canon_alias.content["alias"] and
+            _looks_like_an_alias(canon_alias.content["alias"])
+        ):
+            return canon_alias.content["alias"]
+
+    # at this point we're going to need to search the state by all state keys
+    # for an event type, so rearrange the data structure
+    room_state_bytype = _state_as_two_level_dict(room_state)
+
+    # right then, any aliases at all?
+    if "m.room.aliases" in room_state_bytype:
+        m_room_aliases = room_state_bytype["m.room.aliases"]
+        if len(m_room_aliases.values()) > 0:
+            first_alias_event = m_room_aliases.values()[0]
+            if first_alias_event.content and first_alias_event.content["aliases"]:
+                the_aliases = first_alias_event.content["aliases"]
+                if len(the_aliases) > 0 and _looks_like_an_alias(the_aliases[0]):
+                    return the_aliases[0]
+
+    my_member_event = None
+    if ("m.room.member", user_id) in room_state:
+        my_member_event = room_state[("m.room.member", user_id)]
+
+    if (
+        my_member_event is not None and
+        my_member_event.content['membership'] == "invite"
+    ):
+        if ("m.room.member", my_member_event.sender) in room_state:
+            inviter_member_event = room_state[("m.room.member", my_member_event.sender)]
+            return "Invite from %s" % (name_from_member_event(inviter_member_event),)
+        else:
+            return "Room Invite"
+
+    if not fallback_to_members:
+        return None
+
+    # we're going to have to generate a name based on who's in the room,
+    # so find out who is in the room that isn't the user.
+    if "m.room.member" in room_state_bytype:
+        all_members = [
+            ev for ev in room_state_bytype["m.room.member"].values()
+            if ev.content['membership'] == "join" or ev.content['membership'] == "invite"
+        ]
+        # Sort the member events oldest-first so the we name people in the
+        # order the joined (it should at least be deterministic rather than
+        # dictionary iteration order)
+        all_members.sort(key=lambda e: e.origin_server_ts)
+        other_members = [m for m in all_members if m.state_key != user_id]
+    else:
+        other_members = []
+        all_members = []
+
+    if len(other_members) == 0:
+        if len(all_members) == 1:
+            # self-chat, peeked room with 1 participant,
+            # or inbound invite, or outbound 3PID invite.
+            if all_members[0].sender == user_id:
+                if "m.room.third_party_invite" in room_state_bytype:
+                    third_party_invites = room_state_bytype["m.room.third_party_invite"]
+                    if len(third_party_invites) > 0:
+                        # technically third party invite events are not member
+                        # events, but they are close enough
+                        return "Inviting %s" (
+                            descriptor_from_member_events(third_party_invites)
+                        )
+                    else:
+                        return ALL_ALONE
+            else:
+                return name_from_member_event(all_members[0])
+        else:
+            return ALL_ALONE
+    else:
+        return descriptor_from_member_events(other_members)
+
+
+def descriptor_from_member_events(member_events):
+    if len(member_events) == 0:
+        return "nobody"
+    elif len(member_events) == 1:
+        return name_from_member_event(member_events[0])
+    elif len(member_events) == 2:
+        return "%s and %s" % (
+            name_from_member_event(member_events[0]),
+            name_from_member_event(member_events[1]),
+        )
+    else:
+        return "%s and %d others" % (
+            name_from_member_event(member_events[0]),
+            len(member_events) - 1,
+        )
+
+
+def name_from_member_event(member_event):
+    if (
+        member_event.content and "displayname" in member_event.content and
+        member_event.content["displayname"]
+    ):
+        return member_event.content["displayname"]
+    return member_event.state_key
+
+
+def _state_as_two_level_dict(state):
+    ret = {}
+    for k, v in state.items():
+        ret.setdefault(k[0], {})[k[1]] = v
+    return ret
+
+
+def _looks_like_an_alias(string):
+    return ALIAS_RE.match(string) is not None
\ No newline at end of file