Merge pull request #759 from matrix-org/dbkr/email_notifs

Send email notifications for missed messages

1 files changed, 455 insertions, 0 deletions

diff --git a/synapse/push/mailer.py b/synapse/push/mailer.py
new file mode 100644
index 0000000000..7031fa6d55
--- /dev/null
+++ b/synapse/push/mailer.py
@@ -0,0 +1,455 @@
+# -*- 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
+from twisted.mail.smtp import sendmail
+
+import email.utils
+import email.mime.multipart
+from email.mime.text import MIMEText
+from email.mime.multipart import MIMEMultipart
+
+from synapse.util.async import concurrently_execute
+from synapse.util.presentable_names import (
+    calculate_room_name, name_from_member_event, descriptor_from_member_events
+)
+from synapse.types import UserID
+from synapse.api.errors import StoreError
+from synapse.api.constants import EventTypes
+
+import jinja2
+import bleach
+
+import time
+import urllib
+
+import logging
+logger = logging.getLogger(__name__)
+
+
+MESSAGE_FROM_PERSON_IN_ROOM = "You have a message on %(app)s from %(person)s " \
+                              "in the %s room..."
+MESSAGE_FROM_PERSON = "You have a message on %(app)s from %(person)s..."
+MESSAGES_FROM_PERSON = "You have messages on %(app)s from %(person)s..."
+MESSAGES_IN_ROOM = "There are some messages on %(app)s for you in the %(room)s room..."
+MESSAGES_IN_ROOMS = "Here are some messages on %(app)s you may have missed..."
+INVITE_FROM_PERSON_TO_ROOM = "%(person)s has invited you to join the " \
+                             "%(room)s room on %(app)s..."
+INVITE_FROM_PERSON = "%(person)s has invited you to chat on %(app)s..."
+
+CONTEXT_BEFORE = 1
+CONTEXT_AFTER = 1
+
+# From https://github.com/matrix-org/matrix-react-sdk/blob/master/src/HtmlUtils.js
+ALLOWED_TAGS = [
+    'font',  # custom to matrix for IRC-style font coloring
+    'del',  # for markdown
+    # deliberately no h1/h2 to stop people shouting.
+    'h3', 'h4', 'h5', 'h6', 'blockquote', 'p', 'a', 'ul', 'ol',
+    'nl', 'li', 'b', 'i', 'u', 'strong', 'em', 'strike', 'code', 'hr', 'br', 'div',
+    'table', 'thead', 'caption', 'tbody', 'tr', 'th', 'td', 'pre'
+]
+ALLOWED_ATTRS = {
+    # custom ones first:
+    "font": ["color"],  # custom to matrix
+    "a": ["href", "name", "target"],  # remote target: custom to matrix
+    # We don't currently allow img itself by default, but this
+    # would make sense if we did
+    "img": ["src"],
+}
+# When bleach release a version with this option, we can specify schemes
+# ALLOWED_SCHEMES = ["http", "https", "ftp", "mailto"]
+
+
+class Mailer(object):
+    def __init__(self, hs):
+        self.hs = hs
+        self.store = self.hs.get_datastore()
+        self.state_handler = self.hs.get_state_handler()
+        loader = jinja2.FileSystemLoader(self.hs.config.email_template_dir)
+        self.app_name = self.hs.config.email_app_name
+        env = jinja2.Environment(loader=loader)
+        env.filters["format_ts"] = format_ts_filter
+        env.filters["mxc_to_http"] = self.mxc_to_http_filter
+        self.notif_template_html = env.get_template(
+            self.hs.config.email_notif_template_html
+        )
+        self.notif_template_text = env.get_template(
+            self.hs.config.email_notif_template_text
+        )
+
+    @defer.inlineCallbacks
+    def send_notification_mail(self, user_id, email_address, push_actions):
+        raw_from = email.utils.parseaddr(self.hs.config.email_notif_from)[1]
+        raw_to = email.utils.parseaddr(email_address)[1]
+
+        if raw_to == '':
+            raise RuntimeError("Invalid 'to' address")
+
+        rooms_in_order = deduped_ordered_list(
+            [pa['room_id'] for pa in push_actions]
+        )
+
+        notif_events = yield self.store.get_events(
+            [pa['event_id'] for pa in push_actions]
+        )
+
+        notifs_by_room = {}
+        for pa in push_actions:
+            notifs_by_room.setdefault(pa["room_id"], []).append(pa)
+
+        # collect the current state for all the rooms in which we have
+        # notifications
+        state_by_room = {}
+
+        try:
+            user_display_name = yield self.store.get_profile_displayname(
+                UserID.from_string(user_id).localpart
+            )
+        except StoreError:
+            user_display_name = user_id
+
+        @defer.inlineCallbacks
+        def _fetch_room_state(room_id):
+            room_state = yield self.state_handler.get_current_state(room_id)
+            state_by_room[room_id] = room_state
+
+        # Run at most 3 of these at once: sync does 10 at a time but email
+        # notifs are much realtime than sync so we can afford to wait a bit.
+        yield concurrently_execute(_fetch_room_state, rooms_in_order, 3)
+
+        rooms = []
+
+        for r in rooms_in_order:
+            roomvars = yield self.get_room_vars(
+                r, user_id, notifs_by_room[r], notif_events, state_by_room[r]
+            )
+            rooms.append(roomvars)
+
+        summary_text = self.make_summary_text(
+            notifs_by_room, state_by_room, notif_events, user_id
+        )
+
+        template_vars = {
+            "user_display_name": user_display_name,
+            "unsubscribe_link": self.make_unsubscribe_link(),
+            "summary_text": summary_text,
+            "app_name": self.app_name,
+            "rooms": rooms,
+        }
+
+        html_text = self.notif_template_html.render(**template_vars)
+        html_part = MIMEText(html_text, "html", "utf8")
+
+        plain_text = self.notif_template_text.render(**template_vars)
+        text_part = MIMEText(plain_text, "plain", "utf8")
+
+        multipart_msg = MIMEMultipart('alternative')
+        multipart_msg['Subject'] = "[%s] %s" % (self.app_name, summary_text)
+        multipart_msg['From'] = self.hs.config.email_notif_from
+        multipart_msg['To'] = email_address
+        multipart_msg['Date'] = email.utils.formatdate()
+        multipart_msg['Message-ID'] = email.utils.make_msgid()
+        multipart_msg.attach(text_part)
+        multipart_msg.attach(html_part)
+
+        logger.info("Sending email push notification to %s" % email_address)
+        # logger.debug(html_text)
+
+        yield sendmail(
+            self.hs.config.email_smtp_host,
+            raw_from, raw_to, multipart_msg.as_string(),
+            port=self.hs.config.email_smtp_port
+        )
+
+    @defer.inlineCallbacks
+    def get_room_vars(self, room_id, user_id, notifs, notif_events, room_state):
+        my_member_event = room_state[("m.room.member", user_id)]
+        is_invite = my_member_event.content["membership"] == "invite"
+
+        room_vars = {
+            "title": calculate_room_name(room_state, user_id),
+            "hash": string_ordinal_total(room_id),  # See sender avatar hash
+            "notifs": [],
+            "invite": is_invite,
+            "link": self.make_room_link(room_id),
+        }
+
+        if not is_invite:
+            for n in notifs:
+                notifvars = yield self.get_notif_vars(
+                    n, user_id, notif_events[n['event_id']], room_state
+                )
+
+                # merge overlapping notifs together.
+                # relies on the notifs being in chronological order.
+                merge = False
+                if room_vars['notifs'] and 'messages' in room_vars['notifs'][-1]:
+                    prev_messages = room_vars['notifs'][-1]['messages']
+                    for message in notifvars['messages']:
+                        pm = filter(lambda pm: pm['id'] == message['id'], prev_messages)
+                        if pm:
+                            if not message["is_historical"]:
+                                pm[0]["is_historical"] = False
+                            merge = True
+                        elif merge:
+                            # we're merging, so append any remaining messages
+                            # in this notif to the previous one
+                            prev_messages.append(message)
+
+                if not merge:
+                    room_vars['notifs'].append(notifvars)
+
+        defer.returnValue(room_vars)
+
+    @defer.inlineCallbacks
+    def get_notif_vars(self, notif, user_id, notif_event, room_state):
+        results = yield self.store.get_events_around(
+            notif['room_id'], notif['event_id'],
+            before_limit=CONTEXT_BEFORE, after_limit=CONTEXT_AFTER
+        )
+
+        ret = {
+            "link": self.make_notif_link(notif),
+            "ts": notif['received_ts'],
+            "messages": [],
+        }
+
+        handler = self.hs.get_handlers().message_handler
+        the_events = yield handler.filter_events_for_client(
+            user_id, results["events_before"]
+        )
+        the_events.append(notif_event)
+
+        for event in the_events:
+            messagevars = self.get_message_vars(notif, event, room_state)
+            if messagevars is not None:
+                ret['messages'].append(messagevars)
+
+        defer.returnValue(ret)
+
+    def get_message_vars(self, notif, event, room_state):
+        if event.type != EventTypes.Message:
+            return None
+
+        sender_state_event = room_state[("m.room.member", event.sender)]
+        sender_name = name_from_member_event(sender_state_event)
+        sender_avatar_url = sender_state_event.content["avatar_url"]
+
+        # 'hash' for deterministically picking default images: use
+        # sender_hash % the number of default images to choose from
+        sender_hash = string_ordinal_total(event.sender)
+
+        ret = {
+            "msgtype": event.content["msgtype"],
+            "is_historical": event.event_id != notif['event_id'],
+            "id": event.event_id,
+            "ts": event.origin_server_ts,
+            "sender_name": sender_name,
+            "sender_avatar_url": sender_avatar_url,
+            "sender_hash": sender_hash,
+        }
+
+        if event.content["msgtype"] == "m.text":
+            self.add_text_message_vars(ret, event)
+        elif event.content["msgtype"] == "m.image":
+            self.add_image_message_vars(ret, event)
+
+        if "body" in event.content:
+            ret["body_text_plain"] = event.content["body"]
+
+        return ret
+
+    def add_text_message_vars(self, messagevars, event):
+        if "format" in event.content:
+            msgformat = event.content["format"]
+        else:
+            msgformat = None
+        messagevars["format"] = msgformat
+
+        if msgformat == "org.matrix.custom.html":
+            messagevars["body_text_html"] = safe_markup(event.content["formatted_body"])
+        else:
+            messagevars["body_text_html"] = safe_text(event.content["body"])
+
+        return messagevars
+
+    def add_image_message_vars(self, messagevars, event):
+        messagevars["image_url"] = event.content["url"]
+
+        return messagevars
+
+    def make_summary_text(self, notifs_by_room, state_by_room, notif_events, user_id):
+        if len(notifs_by_room) == 1:
+            # Only one room has new stuff
+            room_id = notifs_by_room.keys()[0]
+
+            # If the room has some kind of name, use it, but we don't
+            # want the generated-from-names one here otherwise we'll
+            # end up with, "new message from Bob in the Bob room"
+            room_name = calculate_room_name(
+                state_by_room[room_id], user_id, fallback_to_members=False
+            )
+
+            my_member_event = state_by_room[room_id][("m.room.member", user_id)]
+            if my_member_event.content["membership"] == "invite":
+                inviter_member_event = state_by_room[room_id][
+                    ("m.room.member", my_member_event.sender)
+                ]
+                inviter_name = name_from_member_event(inviter_member_event)
+
+                if room_name is None:
+                    return INVITE_FROM_PERSON % {
+                        "person": inviter_name,
+                        "app": self.app_name
+                    }
+                else:
+                    return INVITE_FROM_PERSON_TO_ROOM % {
+                        "person": inviter_name,
+                        "room": room_name,
+                        "app": self.app_name,
+                    }
+
+            sender_name = None
+            if len(notifs_by_room[room_id]) == 1:
+                # There is just the one notification, so give some detail
+                event = notif_events[notifs_by_room[room_id][0]["event_id"]]
+                if ("m.room.member", event.sender) in state_by_room[room_id]:
+                    state_event = state_by_room[room_id][("m.room.member", event.sender)]
+                    sender_name = name_from_member_event(state_event)
+
+                if sender_name is not None and room_name is not None:
+                    return MESSAGE_FROM_PERSON_IN_ROOM % {
+                        "person": sender_name,
+                        "room": room_name,
+                        "app": self.app_name,
+                    }
+                elif sender_name is not None:
+                    return MESSAGE_FROM_PERSON % {
+                        "person": sender_name,
+                        "app": self.app_name,
+                    }
+            else:
+                # There's more than one notification for this room, so just
+                # say there are several
+                if room_name is not None:
+                    return MESSAGES_IN_ROOM % {
+                        "room": room_name,
+                        "app": self.app_name,
+                    }
+                else:
+                    # If the room doesn't have a name, say who the messages
+                    # are from explicitly to avoid, "messages in the Bob room"
+                    sender_ids = list(set([
+                        notif_events[n['event_id']].sender
+                        for n in notifs_by_room[room_id]
+                    ]))
+
+                    return MESSAGES_FROM_PERSON % {
+                        "person": descriptor_from_member_events([
+                            state_by_room[room_id][("m.room.member", s)]
+                            for s in sender_ids
+                        ]),
+                        "app": self.app_name,
+                    }
+        else:
+            # Stuff's happened in multiple different rooms
+            return MESSAGES_IN_ROOMS % {
+                "app": self.app_name,
+            }
+
+    def make_room_link(self, room_id):
+        # need /beta for Universal Links to work on iOS
+        if self.app_name == "Vector":
+            return "https://vector.im/beta/#/room/%s" % (room_id,)
+        else:
+            return "https://matrix.to/#/room/%s" % (room_id,)
+
+    def make_notif_link(self, notif):
+        # need /beta for Universal Links to work on iOS
+        if self.app_name == "Vector":
+            return "https://vector.im/beta/#/room/%s/%s" % (
+                notif['room_id'], notif['event_id']
+            )
+        else:
+            return "https://matrix.to/#/room/%s/%s" % (
+                notif['room_id'], notif['event_id']
+            )
+
+    def make_unsubscribe_link(self):
+        # XXX: matrix.to
+        return "https://vector.im/#/settings"
+
+    def mxc_to_http_filter(self, value, width, height, resize_method="crop"):
+        if value[0:6] != "mxc://":
+            return ""
+
+        serverAndMediaId = value[6:]
+        if '#' in serverAndMediaId:
+            (serverAndMediaId, fragment) = serverAndMediaId.split('#', 1)
+            fragment = "#" + fragment
+
+        params = {
+            "width": width,
+            "height": height,
+            "method": resize_method,
+        }
+        return "%s_matrix/media/v1/thumbnail/%s?%s%s" % (
+            self.hs.config.public_baseurl,
+            serverAndMediaId,
+            urllib.urlencode(params),
+            fragment or "",
+        )
+
+
+def safe_markup(raw_html):
+    return jinja2.Markup(bleach.linkify(bleach.clean(
+        raw_html, tags=ALLOWED_TAGS, attributes=ALLOWED_ATTRS,
+        # bleach master has this, but it isn't released yet
+        # protocols=ALLOWED_SCHEMES,
+        strip=True
+    )))
+
+
+def safe_text(raw_text):
+    """
+    Process text: treat it as HTML but escape any tags (ie. just escape the
+    HTML) then linkify it.
+    """
+    return jinja2.Markup(bleach.linkify(bleach.clean(
+        raw_text, tags=[], attributes={},
+        strip=False
+    )))
+
+
+def deduped_ordered_list(l):
+    seen = set()
+    ret = []
+    for item in l:
+        if item not in seen:
+            seen.add(item)
+            ret.append(item)
+    return ret
+
+
+def string_ordinal_total(s):
+    tot = 0
+    for c in s:
+        tot += ord(c)
+    return tot
+
+
+def format_ts_filter(value, format):
+    return time.strftime(format, time.localtime(value / 1000))