forked-synapse/synapse/push/mailer.py

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# 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.
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import logging
import urllib.parse
from typing import TYPE_CHECKING, Any, Dict, Iterable, List, Optional, TypeVar
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import bleach
import jinja2
from synapse.api.constants import EventTypes, Membership
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from synapse.api.errors import StoreError
from synapse.config.emailconfig import EmailSubjectConfig
from synapse.events import EventBase
from synapse.push.presentable_names import (
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calculate_room_name,
descriptor_from_member_events,
name_from_member_event,
)
from synapse.storage.state import StateFilter
from synapse.types import StateMap, UserID
from synapse.util.async_helpers import concurrently_execute
from synapse.visibility import filter_events_for_client
if TYPE_CHECKING:
from synapse.server import HomeServer
logger = logging.getLogger(__name__)
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T = TypeVar("T")
CONTEXT_BEFORE = 1
CONTEXT_AFTER = 1
# From https://github.com/matrix-org/matrix-react-sdk/blob/master/src/HtmlUtils.js
ALLOWED_TAGS = [
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"font", # custom to matrix for IRC-style font coloring
"del", # for markdown
# deliberately no h1/h2 to stop people shouting.
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"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"],
}
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# When bleach release a version with this option, we can specify schemes
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# ALLOWED_SCHEMES = ["http", "https", "ftp", "mailto"]
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class Mailer:
def __init__(
self,
hs: "HomeServer",
app_name: str,
template_html: jinja2.Template,
template_text: jinja2.Template,
):
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self.hs = hs
self.template_html = template_html
self.template_text = template_text
self.send_email_handler = hs.get_send_email_handler()
self.store = self.hs.get_datastore()
self.state_store = self.hs.get_storage().state
self.macaroon_gen = self.hs.get_macaroon_generator()
self.state_handler = self.hs.get_state_handler()
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self.storage = hs.get_storage()
self.app_name = app_name
self.email_subjects = hs.config.email_subjects # type: EmailSubjectConfig
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logger.info("Created Mailer for app_name %s" % app_name)
async def send_password_reset_mail(
self, email_address: str, token: str, client_secret: str, sid: str
) -> None:
"""Send an email with a password reset link to a user
Args:
email_address: Email address we're sending the password
reset to
token: Unique token generated by the server to verify
the email was received
client_secret: Unique token generated by the client to
group together multiple email sending attempts
sid: The generated session ID
"""
params = {"token": token, "client_secret": client_secret, "sid": sid}
link = (
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self.hs.config.public_baseurl
+ "_synapse/client/password_reset/email/submit_token?%s"
% urllib.parse.urlencode(params)
)
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template_vars = {"link": link}
await self.send_email(
email_address,
self.email_subjects.password_reset
% {"server_name": self.hs.config.server_name},
template_vars,
)
async def send_registration_mail(
self, email_address: str, token: str, client_secret: str, sid: str
) -> None:
"""Send an email with a registration confirmation link to a user
Args:
email_address: Email address we're sending the registration
link to
token: Unique token generated by the server to verify
the email was received
client_secret: Unique token generated by the client to
group together multiple email sending attempts
sid: The generated session ID
"""
params = {"token": token, "client_secret": client_secret, "sid": sid}
link = (
self.hs.config.public_baseurl
+ "_matrix/client/unstable/registration/email/submit_token?%s"
% urllib.parse.urlencode(params)
)
template_vars = {"link": link}
await self.send_email(
email_address,
self.email_subjects.email_validation
% {"server_name": self.hs.config.server_name},
template_vars,
)
async def send_add_threepid_mail(
self, email_address: str, token: str, client_secret: str, sid: str
) -> None:
"""Send an email with a validation link to a user for adding a 3pid to their account
Args:
email_address: Email address we're sending the validation link to
token: Unique token generated by the server to verify the email was received
client_secret: Unique token generated by the client to group together
multiple email sending attempts
sid: The generated session ID
"""
params = {"token": token, "client_secret": client_secret, "sid": sid}
link = (
self.hs.config.public_baseurl
+ "_matrix/client/unstable/add_threepid/email/submit_token?%s"
% urllib.parse.urlencode(params)
)
template_vars = {"link": link}
await self.send_email(
email_address,
self.email_subjects.email_validation
% {"server_name": self.hs.config.server_name},
template_vars,
)
async def send_notification_mail(
self,
app_id: str,
user_id: str,
email_address: str,
push_actions: Iterable[Dict[str, Any]],
reason: Dict[str, Any],
) -> None:
"""
Send email regarding a user's room notifications
Params:
app_id: The application receiving the notification.
user_id: The user receiving the notification.
email_address: The email address receiving the notification.
push_actions: All outstanding notifications.
reason: The notification that was ready and is the cause of an email
being sent.
"""
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rooms_in_order = deduped_ordered_list([pa["room_id"] for pa in push_actions])
notif_events = await self.store.get_events(
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[pa["event_id"] for pa in push_actions]
)
notifs_by_room = {} # type: Dict[str, List[Dict[str, Any]]]
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 = await self.store.get_profile_displayname(
UserID.from_string(user_id).localpart
)
if user_display_name is None:
user_display_name = user_id
except StoreError:
user_display_name = user_id
async def _fetch_room_state(room_id: str) -> None:
room_state = await self.store.get_current_state_ids(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 less realtime than sync so we can afford to wait a bit.
await concurrently_execute(_fetch_room_state, rooms_in_order, 3)
# actually sort our so-called rooms_in_order list, most recent room first
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rooms_in_order.sort(key=lambda r: -(notifs_by_room[r][-1]["received_ts"] or 0))
rooms = []
for r in rooms_in_order:
roomvars = await self._get_room_vars(
r, user_id, notifs_by_room[r], notif_events, state_by_room[r]
)
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rooms.append(roomvars)
reason["room_name"] = await calculate_room_name(
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self.store,
state_by_room[reason["room_id"]],
user_id,
fallback_to_members=True,
)
if len(notifs_by_room) == 1:
# Only one room has new stuff
room_id = list(notifs_by_room.keys())[0]
summary_text = await self._make_summary_text_single_room(
room_id,
notifs_by_room[room_id],
state_by_room[room_id],
notif_events,
user_id,
)
else:
summary_text = await self._make_summary_text(
notifs_by_room, state_by_room, notif_events, reason
)
template_vars = {
"user_display_name": user_display_name,
"unsubscribe_link": self._make_unsubscribe_link(
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user_id, app_id, email_address
),
"summary_text": summary_text,
"rooms": rooms,
"reason": reason,
}
await self.send_email(email_address, summary_text, template_vars)
async def send_email(
self, email_address: str, subject: str, extra_template_vars: Dict[str, Any]
) -> None:
"""Send an email with the given information and template text"""
template_vars = {
"app_name": self.app_name,
"server_name": self.hs.config.server.server_name,
}
template_vars.update(extra_template_vars)
html_text = self.template_html.render(**template_vars)
plain_text = self.template_text.render(**template_vars)
await self.send_email_handler.send_email(
email_address=email_address,
subject=subject,
app_name=self.app_name,
html=html_text,
text=plain_text,
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)
async def _get_room_vars(
self,
room_id: str,
user_id: str,
notifs: Iterable[Dict[str, Any]],
notif_events: Dict[str, EventBase],
room_state_ids: StateMap[str],
) -> Dict[str, Any]:
"""
Generate the variables for notifications on a per-room basis.
Args:
room_id: The room ID
user_id: The user receiving the notification.
notifs: The outstanding push actions for this room.
notif_events: The events related to the above notifications.
room_state_ids: The event IDs of the current room state.
Returns:
A dictionary to be added to the template context.
"""
# Check if one of the notifs is an invite event for the user.
is_invite = False
for n in notifs:
ev = notif_events[n["event_id"]]
if ev.type == EventTypes.Member and ev.state_key == user_id:
if ev.content.get("membership") == Membership.INVITE:
is_invite = True
break
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room_name = await calculate_room_name(self.store, room_state_ids, user_id)
room_vars = {
"title": room_name,
"hash": string_ordinal_total(room_id), # See sender avatar hash
"notifs": [],
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"invite": is_invite,
"link": self._make_room_link(room_id),
} # type: Dict[str, Any]
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if not is_invite:
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for n in notifs:
notifvars = await self._get_notif_vars(
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n, user_id, notif_events[n["event_id"]], room_state_ids
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)
# merge overlapping notifs together.
# relies on the notifs being in chronological order.
merge = False
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if room_vars["notifs"] and "messages" in room_vars["notifs"][-1]:
prev_messages = room_vars["notifs"][-1]["messages"]
for message in notifvars["messages"]:
pm = list(
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:
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room_vars["notifs"].append(notifvars)
return room_vars
async def _get_notif_vars(
self,
notif: Dict[str, Any],
user_id: str,
notif_event: EventBase,
room_state_ids: StateMap[str],
) -> Dict[str, Any]:
"""
Generate the variables for a single notification.
Args:
notif: The outstanding notification for this room.
user_id: The user receiving the notification.
notif_event: The event related to the above notification.
room_state_ids: The event IDs of the current room state.
Returns:
A dictionary to be added to the template context.
"""
results = await self.store.get_events_around(
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notif["room_id"],
notif["event_id"],
before_limit=CONTEXT_BEFORE,
after_limit=CONTEXT_AFTER,
)
ret = {
"link": self._make_notif_link(notif),
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"ts": notif["received_ts"],
"messages": [],
}
the_events = await filter_events_for_client(
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self.storage, user_id, results["events_before"]
)
the_events.append(notif_event)
for event in the_events:
messagevars = await self._get_message_vars(notif, event, room_state_ids)
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if messagevars is not None:
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ret["messages"].append(messagevars)
return ret
async def _get_message_vars(
self, notif: Dict[str, Any], event: EventBase, room_state_ids: StateMap[str]
) -> Optional[Dict[str, Any]]:
"""
Generate the variables for a single event, if possible.
Args:
notif: The outstanding notification for this room.
event: The event under consideration.
room_state_ids: The event IDs of the current room state.
Returns:
A dictionary to be added to the template context, or None if the
event cannot be processed.
"""
if event.type != EventTypes.Message and event.type != EventTypes.Encrypted:
return None
# Get the sender's name and avatar from the room state.
type_state_key = ("m.room.member", event.sender)
sender_state_event_id = room_state_ids.get(type_state_key)
if sender_state_event_id:
sender_state_event = await self.store.get_event(
sender_state_event_id
) # type: Optional[EventBase]
else:
# Attempt to check the historical state for the room.
historical_state = await self.state_store.get_state_for_event(
event.event_id, StateFilter.from_types((type_state_key,))
)
sender_state_event = historical_state.get(type_state_key)
if sender_state_event:
sender_name = name_from_member_event(sender_state_event)
sender_avatar_url = sender_state_event.content.get("avatar_url")
else:
# No state could be found, fallback to the MXID.
sender_name = event.sender
sender_avatar_url = None
# '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 = {
"event_type": event.type,
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"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,
}
# Encrypted messages don't have any additional useful information.
if event.type == EventTypes.Encrypted:
return ret
msgtype = event.content.get("msgtype")
ret["msgtype"] = msgtype
if msgtype == "m.text":
self._add_text_message_vars(ret, event)
elif msgtype == "m.image":
self._add_image_message_vars(ret, event)
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if "body" in event.content:
ret["body_text_plain"] = event.content["body"]
return ret
def _add_text_message_vars(
self, messagevars: Dict[str, Any], event: EventBase
) -> None:
"""
Potentially add a sanitised message body to the message variables.
Args:
messagevars: The template context to be modified.
event: The event under consideration.
"""
msgformat = event.content.get("format")
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messagevars["format"] = msgformat
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formatted_body = event.content.get("formatted_body")
body = event.content.get("body")
if msgformat == "org.matrix.custom.html" and formatted_body:
messagevars["body_text_html"] = safe_markup(formatted_body)
elif body:
messagevars["body_text_html"] = safe_text(body)
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def _add_image_message_vars(
self, messagevars: Dict[str, Any], event: EventBase
) -> None:
"""
Potentially add an image URL to the message variables.
Args:
messagevars: The template context to be modified.
event: The event under consideration.
"""
if "url" in event.content:
messagevars["image_url"] = event.content["url"]
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async def _make_summary_text_single_room(
self,
room_id: str,
notifs: List[Dict[str, Any]],
room_state_ids: StateMap[str],
notif_events: Dict[str, EventBase],
user_id: str,
) -> str:
"""
Make a summary text for the email when only a single room has notifications.
Args:
room_id: The ID of the room.
notifs: The push actions for this room.
room_state_ids: The state map for the room.
notif_events: A map of event ID -> notification event.
user_id: The user receiving the notification.
Returns:
The summary text.
"""
# 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 = await calculate_room_name(
self.store, room_state_ids, user_id, fallback_to_members=False
)
# See if one of the notifs is an invite event for the user
invite_event = None
for n in notifs:
ev = notif_events[n["event_id"]]
if ev.type == EventTypes.Member and ev.state_key == user_id:
if ev.content.get("membership") == Membership.INVITE:
invite_event = ev
break
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if invite_event:
inviter_member_event_id = room_state_ids.get(
("m.room.member", invite_event.sender)
)
inviter_name = invite_event.sender
if inviter_member_event_id:
inviter_member_event = await self.store.get_event(
inviter_member_event_id, allow_none=True
)
if inviter_member_event:
inviter_name = name_from_member_event(inviter_member_event)
if room_name is None:
return self.email_subjects.invite_from_person % {
"person": inviter_name,
"app": self.app_name,
}
return self.email_subjects.invite_from_person_to_room % {
"person": inviter_name,
"room": room_name,
"app": self.app_name,
}
if len(notifs) == 1:
# There is just the one notification, so give some detail
sender_name = None
event = notif_events[notifs[0]["event_id"]]
if ("m.room.member", event.sender) in room_state_ids:
state_event_id = room_state_ids[("m.room.member", event.sender)]
state_event = await self.store.get_event(state_event_id)
sender_name = name_from_member_event(state_event)
if sender_name is not None and room_name is not None:
return self.email_subjects.message_from_person_in_room % {
"person": sender_name,
"room": room_name,
"app": self.app_name,
}
elif sender_name is not None:
return self.email_subjects.message_from_person % {
"person": sender_name,
"app": self.app_name,
}
# The sender is unknown, just use the room name (or ID).
return self.email_subjects.messages_in_room % {
"room": room_name or room_id,
"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 self.email_subjects.messages_in_room % {
"room": room_name,
"app": self.app_name,
}
return await self._make_summary_text_from_member_events(
room_id, notifs, room_state_ids, notif_events
)
async def _make_summary_text(
self,
notifs_by_room: Dict[str, List[Dict[str, Any]]],
room_state_ids: Dict[str, StateMap[str]],
notif_events: Dict[str, EventBase],
reason: Dict[str, Any],
) -> str:
"""
Make a summary text for the email when multiple rooms have notifications.
Args:
notifs_by_room: A map of room ID to the push actions for that room.
room_state_ids: A map of room ID to the state map for that room.
notif_events: A map of event ID -> notification event.
reason: The reason this notification is being sent.
Returns:
The summary text.
"""
# Stuff's happened in multiple different rooms
# ...but we still refer to the 'reason' room which triggered the mail
if reason["room_name"] is not None:
return self.email_subjects.messages_in_room_and_others % {
"room": reason["room_name"],
"app": self.app_name,
}
room_id = reason["room_id"]
return await self._make_summary_text_from_member_events(
room_id, notifs_by_room[room_id], room_state_ids[room_id], notif_events
)
async def _make_summary_text_from_member_events(
self,
room_id: str,
notifs: List[Dict[str, Any]],
room_state_ids: StateMap[str],
notif_events: Dict[str, EventBase],
) -> str:
"""
Make a summary text for the email when only a single room has notifications.
Args:
room_id: The ID of the room.
notifs: The push actions for this room.
room_state_ids: The state map for the room.
notif_events: A map of event ID -> notification event.
Returns:
The summary text.
"""
# If the room doesn't have a name, say who the messages
# are from explicitly to avoid, "messages in the Bob room"
# Find the latest event ID for each sender, note that the notifications
# are already in descending received_ts.
sender_ids = {}
for n in notifs:
sender = notif_events[n["event_id"]].sender
if sender not in sender_ids:
sender_ids[sender] = n["event_id"]
# Get the actual member events (in order to calculate a pretty name for
# the room).
member_event_ids = []
member_events = {}
for sender_id, event_id in sender_ids.items():
type_state_key = ("m.room.member", sender_id)
sender_state_event_id = room_state_ids.get(type_state_key)
if sender_state_event_id:
member_event_ids.append(sender_state_event_id)
else:
# Attempt to check the historical state for the room.
historical_state = await self.state_store.get_state_for_event(
event_id, StateFilter.from_types((type_state_key,))
)
sender_state_event = historical_state.get(type_state_key)
if sender_state_event:
member_events[event_id] = sender_state_event
member_events.update(await self.store.get_events(member_event_ids))
if not member_events:
# No member events were found! Maybe the room is empty?
# Fallback to the room ID (note that if there was a room name this
# would already have been used previously).
return self.email_subjects.messages_in_room % {
"room": room_id,
"app": self.app_name,
}
# There was a single sender.
if len(member_events) == 1:
return self.email_subjects.messages_from_person % {
"person": descriptor_from_member_events(member_events.values()),
"app": self.app_name,
}
# There was more than one sender, use the first one and a tweaked template.
return self.email_subjects.messages_from_person_and_others % {
"person": descriptor_from_member_events(list(member_events.values())[:1]),
"app": self.app_name,
}
def _make_room_link(self, room_id: str) -> str:
"""
Generate a link to open a room in the web client.
Args:
room_id: The room ID to generate a link to.
Returns:
A link to open a room in the web client.
"""
if self.hs.config.email_riot_base_url:
base_url = "%s/#/room" % (self.hs.config.email_riot_base_url)
elif self.app_name == "Vector":
# need /beta for Universal Links to work on iOS
base_url = "https://vector.im/beta/#/room"
else:
base_url = "https://matrix.to/#"
return "%s/%s" % (base_url, room_id)
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def _make_notif_link(self, notif: Dict[str, str]) -> str:
"""
Generate a link to open an event in the web client.
Args:
notif: The notification to generate a link for.
Returns:
A link to open the notification in the web client.
"""
if self.hs.config.email_riot_base_url:
return "%s/#/room/%s/%s" % (
self.hs.config.email_riot_base_url,
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notif["room_id"],
notif["event_id"],
)
elif self.app_name == "Vector":
# need /beta for Universal Links to work on iOS
return "https://vector.im/beta/#/room/%s/%s" % (
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notif["room_id"],
notif["event_id"],
)
else:
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return "https://matrix.to/#/%s/%s" % (notif["room_id"], notif["event_id"])
def _make_unsubscribe_link(
self, user_id: str, app_id: str, email_address: str
) -> str:
"""
Generate a link to unsubscribe from email notifications.
Args:
user_id: The user receiving the notification.
app_id: The application receiving the notification.
email_address: The email address receiving the notification.
Returns:
A link to unsubscribe from email notifications.
"""
params = {
"access_token": self.macaroon_gen.generate_delete_pusher_token(user_id),
"app_id": app_id,
"pushkey": email_address,
}
# XXX: make r0 once API is stable
return "%s_matrix/client/unstable/pushers/remove?%s" % (
self.hs.config.public_baseurl,
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urllib.parse.urlencode(params),
)
def safe_markup(raw_html: str) -> jinja2.Markup:
"""
Sanitise a raw HTML string to a set of allowed tags and attributes, and linkify any bare URLs.
Args
raw_html: Unsafe HTML.
Returns:
A Markup object ready to safely use in a Jinja template.
"""
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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: str) -> jinja2.Markup:
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"""
Sanitise text (escape any HTML tags), and then linkify any bare URLs.
Args
raw_text: Unsafe text which might include HTML markup.
Returns:
A Markup object ready to safely use in a Jinja template.
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"""
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return jinja2.Markup(
bleach.linkify(bleach.clean(raw_text, tags=[], attributes={}, strip=False))
)
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def deduped_ordered_list(it: Iterable[T]) -> List[T]:
seen = set()
ret = []
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for item in it:
if item not in seen:
seen.add(item)
ret.append(item)
return ret
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def string_ordinal_total(s: str) -> int:
tot = 0
for c in s:
tot += ord(c)
return tot