# -*- coding: utf-8 -*- import base64 import binascii from functools import partial import logging import lxml.html as LH import os import re import time import random from typing import Any, Dict, List, Optional, SupportsInt, Tuple, Type, Union, cast from django.conf import settings from django.db import IntegrityError, transaction from django.utils.timezone import now as timezone_now from django.utils.translation import ugettext as _ from gcm import GCM import requests import urllib import ujson from zerver.decorator import statsd_increment from zerver.lib.avatar import absolute_avatar_url from zerver.lib.exceptions import ErrorCode, JsonableError from zerver.lib.message import access_message, huddle_users from zerver.lib.queue import retry_event from zerver.lib.timestamp import datetime_to_timestamp, timestamp_to_datetime from zerver.lib.utils import generate_random_token from zerver.models import PushDeviceToken, Message, Recipient, UserProfile, \ UserMessage, get_display_recipient, receives_offline_push_notifications, \ receives_online_notifications, receives_stream_notifications, get_user_profile_by_id, \ ArchivedMessage from version import ZULIP_VERSION logger = logging.getLogger(__name__) if settings.ZILENCER_ENABLED: from zilencer.models import RemotePushDeviceToken else: # nocoverage -- Not convenient to add test for this. from mock import Mock RemotePushDeviceToken = Mock() # type: ignore # https://github.com/JukkaL/mypy/issues/1188 DeviceToken = Union[PushDeviceToken, RemotePushDeviceToken] # We store the token as b64, but apns-client wants hex strings def b64_to_hex(data: bytes) -> str: return binascii.hexlify(base64.b64decode(data)).decode('utf-8') def hex_to_b64(data: str) -> bytes: return base64.b64encode(binascii.unhexlify(data.encode('utf-8'))) # # Sending to APNs, for iOS # _apns_client = None # type: Optional[Any] _apns_client_initialized = False def get_apns_client() -> Any: # We lazily do this import as part of optimizing Zulip's base # import time. from apns2.client import APNsClient global _apns_client, _apns_client_initialized if not _apns_client_initialized: # NB if called concurrently, this will make excess connections. # That's a little sloppy, but harmless unless a server gets # hammered with a ton of these all at once after startup. if settings.APNS_CERT_FILE is not None: _apns_client = APNsClient(credentials=settings.APNS_CERT_FILE, use_sandbox=settings.APNS_SANDBOX) _apns_client_initialized = True return _apns_client def apns_enabled() -> bool: client = get_apns_client() return client is not None def modernize_apns_payload(data: Dict[str, Any]) -> Dict[str, Any]: '''Take a payload in an unknown Zulip version's format, and return in current format.''' # TODO this isn't super robust as is -- if a buggy remote server # sends a malformed payload, we are likely to raise an exception. if 'message_ids' in data: # The format sent by 1.6.0, from the earliest pre-1.6.0 # version with bouncer support up until 613d093d7 pre-1.7.0: # 'alert': str, # just sender, and text about PM/group-PM/mention # 'message_ids': List[int], # always just one return { 'alert': data['alert'], 'badge': 0, 'custom': { 'zulip': { 'message_ids': data['message_ids'], }, }, } else: # Something already compatible with the current format. # `alert` may be a string, or a dict with `title` and `body`. # In 1.7.0 and 1.7.1, before 0912b5ba8 pre-1.8.0, the only # item in `custom.zulip` is `message_ids`. return data APNS_MAX_RETRIES = 3 @statsd_increment("apple_push_notification") def send_apple_push_notification(user_id: int, devices: List[DeviceToken], payload_data: Dict[str, Any], remote: bool=False) -> None: # We lazily do the APNS imports as part of optimizing Zulip's base # import time; since these are only needed in the push # notification queue worker, it's best to only import them in the # code that needs them. from apns2.payload import Payload as APNsPayload from apns2.client import APNsClient from hyper.http20.exceptions import HTTP20Error client = get_apns_client() # type: APNsClient if client is None: logger.debug("APNs: Dropping a notification because nothing configured. " "Set PUSH_NOTIFICATION_BOUNCER_URL (or APNS_CERT_FILE).") return if remote: DeviceTokenClass = RemotePushDeviceToken else: DeviceTokenClass = PushDeviceToken logger.info("APNs: Sending notification for user %d to %d devices", user_id, len(devices)) payload = APNsPayload(**modernize_apns_payload(payload_data)) expiration = int(time.time() + 24 * 3600) retries_left = APNS_MAX_RETRIES for device in devices: # TODO obviously this should be made to actually use the async def attempt_send() -> Optional[str]: try: stream_id = client.send_notification_async( device.token, payload, topic='org.zulip.Zulip', expiration=expiration) return client.get_notification_result(stream_id) except HTTP20Error as e: logger.warning("APNs: HTTP error sending for user %d to device %s: %s", user_id, device.token, e.__class__.__name__) return None except BrokenPipeError as e: logger.warning("APNs: BrokenPipeError sending for user %d to device %s: %s", user_id, device.token, e.__class__.__name__) return None except ConnectionError as e: # nocoverage logger.warning("APNs: ConnectionError sending for user %d to device %s: %s", user_id, device.token, e.__class__.__name__) return None result = attempt_send() while result is None and retries_left > 0: retries_left -= 1 result = attempt_send() if result is None: result = "HTTP error, retries exhausted" if result[0] == "Unregistered": # For some reason, "Unregistered" result values have a # different format, as a tuple of the pair ("Unregistered", 12345132131). result = result[0] # type: ignore # APNS API is inconsistent if result == 'Success': logger.info("APNs: Success sending for user %d to device %s", user_id, device.token) elif result in ["Unregistered", "BadDeviceToken", "DeviceTokenNotForTopic"]: logger.info("APNs: Removing invalid/expired token %s (%s)" % (device.token, result)) # We remove all entries for this token (There # could be multiple for different Zulip servers). DeviceTokenClass.objects.filter(token=device.token, kind=DeviceTokenClass.APNS).delete() else: logger.warning("APNs: Failed to send for user %d to device %s: %s", user_id, device.token, result) # # Sending to GCM, for Android # if settings.ANDROID_GCM_API_KEY: # nocoverage gcm = GCM(settings.ANDROID_GCM_API_KEY) else: gcm = None def gcm_enabled() -> bool: # nocoverage return gcm is not None def send_android_push_notification_to_user(user_profile: UserProfile, data: Dict[str, Any]) -> None: devices = list(PushDeviceToken.objects.filter(user=user_profile, kind=PushDeviceToken.GCM)) send_android_push_notification(devices, data) @statsd_increment("android_push_notification") def send_android_push_notification(devices: List[DeviceToken], data: Dict[str, Any], remote: bool=False) -> None: if not gcm: logger.debug("Skipping sending a GCM push notification since " "PUSH_NOTIFICATION_BOUNCER_URL and ANDROID_GCM_API_KEY are both unset") return reg_ids = [device.token for device in devices] if remote: DeviceTokenClass = RemotePushDeviceToken else: DeviceTokenClass = PushDeviceToken try: res = gcm.json_request(registration_ids=reg_ids, data=data, retries=10) except IOError as e: logger.warning(str(e)) return if res and 'success' in res: for reg_id, msg_id in res['success'].items(): logger.info("GCM: Sent %s as %s" % (reg_id, msg_id)) # res.canonical will contain results when there are duplicate registrations for the same # device. The "canonical" registration is the latest registration made by the device. # Ref: http://developer.android.com/google/gcm/adv.html#canonical if 'canonical' in res: for reg_id, new_reg_id in res['canonical'].items(): if reg_id == new_reg_id: # I'm not sure if this should happen. In any case, not really actionable. logger.warning("GCM: Got canonical ref but it already matches our ID %s!" % (reg_id,)) elif not DeviceTokenClass.objects.filter(token=new_reg_id, kind=DeviceTokenClass.GCM).count(): # This case shouldn't happen; any time we get a canonical ref it should have been # previously registered in our system. # # That said, recovery is easy: just update the current PDT object to use the new ID. logger.warning( "GCM: Got canonical ref %s replacing %s but new ID not registered! Updating." % (new_reg_id, reg_id)) DeviceTokenClass.objects.filter( token=reg_id, kind=DeviceTokenClass.GCM).update(token=new_reg_id) else: # Since we know the new ID is registered in our system we can just drop the old one. logger.info("GCM: Got canonical ref %s, dropping %s" % (new_reg_id, reg_id)) DeviceTokenClass.objects.filter(token=reg_id, kind=DeviceTokenClass.GCM).delete() if 'errors' in res: for error, reg_ids in res['errors'].items(): if error in ['NotRegistered', 'InvalidRegistration']: for reg_id in reg_ids: logger.info("GCM: Removing %s" % (reg_id,)) # We remove all entries for this token (There # could be multiple for different Zulip servers). DeviceTokenClass.objects.filter(token=reg_id, kind=DeviceTokenClass.GCM).delete() else: for reg_id in reg_ids: logger.warning("GCM: Delivery to %s failed: %s" % (reg_id, error)) # python-gcm handles retrying of the unsent messages. # Ref: https://github.com/geeknam/python-gcm/blob/master/gcm/gcm.py#L497 # # Sending to a bouncer # def uses_notification_bouncer() -> bool: return settings.PUSH_NOTIFICATION_BOUNCER_URL is not None def send_notifications_to_bouncer(user_profile_id: int, apns_payload: Dict[str, Any], gcm_payload: Dict[str, Any]) -> None: post_data = { 'user_id': user_profile_id, 'apns_payload': apns_payload, 'gcm_payload': gcm_payload, } # Calls zilencer.views.remote_server_notify_push send_json_to_push_bouncer('POST', 'notify', post_data) def send_json_to_push_bouncer(method: str, endpoint: str, post_data: Dict[str, Any]) -> None: send_to_push_bouncer( method, endpoint, ujson.dumps(post_data), extra_headers={"Content-type": "application/json"}, ) class PushNotificationBouncerException(Exception): pass def send_to_push_bouncer(method: str, endpoint: str, post_data: Union[str, Dict[str, Any]], extra_headers: Optional[Dict[str, Any]]=None) -> None: """While it does actually send the notice, this function has a lot of code and comments around error handling for the push notifications bouncer. There are several classes of failures, each with its own potential solution: * Network errors with requests.request. We let those happen normally. * 500 errors from the push bouncer or other unexpected responses; we don't try to parse the response, but do make clear the cause. * 400 errors from the push bouncer. Here there are 2 categories: Our server failed to connect to the push bouncer (should throw) vs. client-side errors like and invalid token. """ url = urllib.parse.urljoin(settings.PUSH_NOTIFICATION_BOUNCER_URL, '/api/v1/remotes/push/' + endpoint) api_auth = requests.auth.HTTPBasicAuth(settings.ZULIP_ORG_ID, settings.ZULIP_ORG_KEY) headers = {"User-agent": "ZulipServer/%s" % (ZULIP_VERSION,)} if extra_headers is not None: headers.update(extra_headers) res = requests.request(method, url, data=post_data, auth=api_auth, timeout=30, verify=True, headers=headers) if res.status_code >= 500: # 500s should be resolved by the people who run the push # notification bouncer service, since they'll get an email # too. For now we email the server admin, but we'll likely # want to do some sort of retry logic eventually. raise PushNotificationBouncerException( _("Received 500 from push notification bouncer")) elif res.status_code >= 400: # If JSON parsing errors, just let that exception happen result_dict = ujson.loads(res.content) msg = result_dict['msg'] if 'code' in result_dict and result_dict['code'] == 'INVALID_ZULIP_SERVER': # Invalid Zulip server credentials should email this server's admins raise PushNotificationBouncerException( _("Push notifications bouncer error: %s") % (msg,)) else: # But most other errors coming from the push bouncer # server are client errors (e.g. never-registered token) # and should be handled as such. raise JsonableError(msg) elif res.status_code != 200: # Anything else is unexpected and likely suggests a bug in # this version of Zulip, so we throw an exception that will # email the server admins. raise PushNotificationBouncerException( "Push notification bouncer returned unexpected status code %s" % (res.status_code,)) # If we don't throw an exception, it's a successful bounce! # # Managing device tokens # def num_push_devices_for_user(user_profile: UserProfile, kind: Optional[int]=None) -> PushDeviceToken: if kind is None: return PushDeviceToken.objects.filter(user=user_profile).count() else: return PushDeviceToken.objects.filter(user=user_profile, kind=kind).count() def add_push_device_token(user_profile: UserProfile, token_str: bytes, kind: int, ios_app_id: Optional[str]=None) -> None: logger.info("Registering push device: %d %r %d %r", user_profile.id, token_str, kind, ios_app_id) # If we're sending things to the push notification bouncer # register this user with them here if uses_notification_bouncer(): post_data = { 'server_uuid': settings.ZULIP_ORG_ID, 'user_id': user_profile.id, 'token': token_str, 'token_kind': kind, } if kind == PushDeviceToken.APNS: post_data['ios_app_id'] = ios_app_id logger.info("Sending new push device to bouncer: %r", post_data) # Calls zilencer.views.register_remote_push_device send_to_push_bouncer('POST', 'register', post_data) return try: with transaction.atomic(): PushDeviceToken.objects.create( user_id=user_profile.id, kind=kind, token=token_str, ios_app_id=ios_app_id, # last_updated is to be renamed to date_created. last_updated=timezone_now()) except IntegrityError: pass def remove_push_device_token(user_profile: UserProfile, token_str: bytes, kind: int) -> None: # If we're sending things to the push notification bouncer # unregister this user with them here if uses_notification_bouncer(): # TODO: Make this a remove item post_data = { 'server_uuid': settings.ZULIP_ORG_ID, 'user_id': user_profile.id, 'token': token_str, 'token_kind': kind, } # Calls zilencer.views.unregister_remote_push_device send_to_push_bouncer("POST", "unregister", post_data) return try: token = PushDeviceToken.objects.get(token=token_str, kind=kind, user=user_profile) token.delete() except PushDeviceToken.DoesNotExist: raise JsonableError(_("Token does not exist")) # # Push notifications in general # def push_notifications_enabled() -> bool: '''True just if this server has configured a way to send push notifications.''' if (uses_notification_bouncer() and settings.ZULIP_ORG_KEY is not None and settings.ZULIP_ORG_ID is not None): # nocoverage # We have the needed configuration to send push notifications through # the bouncer. Better yet would be to confirm that this config actually # works -- e.g., that we have ever successfully sent to the bouncer -- # but this is a good start. return True if apns_enabled() and gcm_enabled(): # nocoverage # We have the needed configuration to send through APNs and GCM directly # (i.e., we are the bouncer, presumably.) Again, assume it actually works. return True return False def initialize_push_notifications() -> None: if not push_notifications_enabled(): if settings.DEVELOPMENT and not settings.TEST_SUITE: # nocoverage # Avoid unnecessary spam on development environment startup return logger.warning("Mobile push notifications are not configured.\n " "See https://zulip.readthedocs.io/en/latest/" "production/mobile-push-notifications.html") def get_gcm_alert(message: Message) -> str: """ Determine what alert string to display based on the missed messages. """ sender_str = message.sender.full_name if message.recipient.type == Recipient.HUDDLE and message.trigger == 'private_message': return "New private group message from %s" % (sender_str,) elif message.recipient.type == Recipient.PERSONAL and message.trigger == 'private_message': return "New private message from %s" % (sender_str,) elif message.is_stream_message() and message.trigger == 'mentioned': return "New mention from %s" % (sender_str,) else: # message.is_stream_message() and message.trigger == 'stream_push_notify' return "New stream message from %s in %s" % (sender_str, get_display_recipient(message.recipient),) def get_mobile_push_content(rendered_content: str) -> str: def get_text(elem: LH.HtmlElement) -> str: # Convert default emojis to their unicode equivalent. classes = elem.get("class", "") if "emoji" in classes: match = re.search(r"emoji-(?P\S+)", classes) if match: emoji_code = match.group('emoji_code') char_repr = "" for codepoint in emoji_code.split('-'): char_repr += chr(int(codepoint, 16)) return char_repr # Handles realm emojis, avatars etc. if elem.tag == "img": return elem.get("alt", "") if elem.tag == 'blockquote': return '' # To avoid empty line before quote text return elem.text or '' def format_as_quote(quote_text: str) -> str: quote_text_list = filter(None, quote_text.split('\n')) # Remove empty lines quote_text = '\n'.join(map(lambda x: "> "+x, quote_text_list)) quote_text += '\n' return quote_text def process(elem: LH.HtmlElement) -> str: plain_text = get_text(elem) sub_text = '' for child in elem: sub_text += process(child) if elem.tag == 'blockquote': sub_text = format_as_quote(sub_text) plain_text += sub_text plain_text += elem.tail or "" return plain_text if settings.PUSH_NOTIFICATION_REDACT_CONTENT: return "***REDACTED***" elem = LH.fromstring(rendered_content) plain_text = process(elem) return plain_text def truncate_content(content: str) -> Tuple[str, bool]: # We use unicode character 'HORIZONTAL ELLIPSIS' (U+2026) instead # of three dots as this saves two extra characters for textual # content. This function will need to be updated to handle unicode # combining characters and tags when we start supporting themself. if len(content) <= 200: return content, False return content[:200] + "…", True def get_common_payload(message: Message) -> Dict[str, Any]: data = {} # type: Dict[str, Any] # These will let the app support logging into multiple realms and servers. data['server'] = settings.EXTERNAL_HOST data['realm_id'] = message.sender.realm.id data['realm_uri'] = message.sender.realm.uri # `sender_id` is preferred, but some existing versions use `sender_email`. data['sender_id'] = message.sender.id data['sender_email'] = message.sender.email if message.recipient.type == Recipient.STREAM: data['recipient_type'] = "stream" data['stream'] = get_display_recipient(message.recipient) data['topic'] = message.topic_name() elif message.recipient.type == Recipient.HUDDLE: data['recipient_type'] = "private" data['pm_users'] = huddle_users(message.recipient.id) else: # Recipient.PERSONAL data['recipient_type'] = "private" return data def get_apns_alert_title(message: Message) -> str: """ On an iOS notification, this is the first bolded line. """ if message.recipient.type == Recipient.HUDDLE: recipients = cast(List[Dict[str, Any]], get_display_recipient(message.recipient)) return ', '.join(sorted(r['full_name'] for r in recipients)) elif message.is_stream_message(): return "#%s > %s" % (get_display_recipient(message.recipient), message.topic_name(),) # For personal PMs, we just show the sender name. return message.sender.full_name def get_apns_alert_subtitle(message: Message) -> str: """ On an iOS notification, this is the second bolded line. """ if message.trigger == "mentioned": return message.sender.full_name + " mentioned you:" elif message.recipient.type == Recipient.PERSONAL: return "" # For group PMs, or regular messages to a stream, just use a colon to indicate this is the sender. return message.sender.full_name + ":" def get_apns_payload(user_profile: UserProfile, message: Message) -> Dict[str, Any]: zulip_data = get_common_payload(message) zulip_data.update({ 'message_ids': [message.id], }) content, _ = truncate_content(get_mobile_push_content(message.rendered_content)) apns_data = { 'alert': { 'title': get_apns_alert_title(message), 'subtitle': get_apns_alert_subtitle(message), 'body': content, }, 'sound': 'default', 'badge': 0, # TODO: set badge count in a better way 'custom': {'zulip': zulip_data}, } return apns_data def get_gcm_payload(user_profile: UserProfile, message: Message) -> Dict[str, Any]: data = get_common_payload(message) content, truncated = truncate_content(get_mobile_push_content(message.rendered_content)) data.update({ 'user': user_profile.email, 'event': 'message', 'alert': get_gcm_alert(message), 'zulip_message_id': message.id, # message_id is reserved for CCS 'time': datetime_to_timestamp(message.pub_date), 'content': content, 'content_truncated': truncated, 'sender_full_name': message.sender.full_name, 'sender_avatar_url': absolute_avatar_url(message.sender), }) return data def handle_remove_push_notification(user_profile_id: int, message_id: int) -> None: """This should be called when a message that had previously had a mobile push executed is read. This triggers a mobile push notifica mobile app when the message is read on the server, to remove the message from the notification. """ user_profile = get_user_profile_by_id(user_profile_id) message, user_message = access_message(user_profile, message_id) if not settings.SEND_REMOVE_PUSH_NOTIFICATIONS: # It's a little annoying that we duplicate this flag-clearing # code (also present below), but this block is scheduled to be # removed in a few weeks, once the app has supported the # feature for long enough. user_message.flags.active_mobile_push_notification = False user_message.save(update_fields=["flags"]) return gcm_payload = get_common_payload(message) gcm_payload.update({ 'event': 'remove', 'zulip_message_id': message_id, # message_id is reserved for CCS }) if uses_notification_bouncer(): try: send_notifications_to_bouncer(user_profile_id, {}, gcm_payload) except requests.ConnectionError: # nocoverage def failure_processor(event: Dict[str, Any]) -> None: logger.warning( "Maximum retries exceeded for trigger:%s event:push_notification" % ( event['user_profile_id'])) return android_devices = list(PushDeviceToken.objects.filter(user=user_profile, kind=PushDeviceToken.GCM)) if android_devices: send_android_push_notification(android_devices, gcm_payload) user_message.flags.active_mobile_push_notification = False user_message.save(update_fields=["flags"]) @statsd_increment("push_notifications") def handle_push_notification(user_profile_id: int, missed_message: Dict[str, Any]) -> None: """ missed_message is the event received by the zerver.worker.queue_processors.PushNotificationWorker.consume function. """ if not push_notifications_enabled(): return user_profile = get_user_profile_by_id(user_profile_id) if not (receives_offline_push_notifications(user_profile) or receives_online_notifications(user_profile)): return user_profile = get_user_profile_by_id(user_profile_id) try: (message, user_message) = access_message(user_profile, missed_message['message_id']) except JsonableError: if ArchivedMessage.objects.filter(id=missed_message['message_id']).exists(): # If the cause is a race with the message being deleted, # that's normal and we have no need to log an error. return logging.error("Unexpected message access failure handling push notifications: %s %s" % ( user_profile.id, missed_message['message_id'])) return if user_message is not None: # If the user has read the message already, don't push-notify. # # TODO: It feels like this is already handled when things are # put in the queue; maybe we should centralize this logic with # the `zerver/tornado/event_queue.py` logic? if user_message.flags.read: return # Otherwise, we mark the message as having an active mobile # push notification, so that we can send revocation messages # later. user_message.flags.active_mobile_push_notification = True user_message.save(update_fields=["flags"]) else: # Users should only be getting push notifications into this # queue for messages they haven't received if they're # long-term idle; anything else is likely a bug. if not user_profile.long_term_idle: logger.error("Could not find UserMessage with message_id %s and user_id %s" % ( missed_message['message_id'], user_profile_id)) return message.trigger = missed_message['trigger'] apns_payload = get_apns_payload(user_profile, message) gcm_payload = get_gcm_payload(user_profile, message) logger.info("Sending push notifications to mobile clients for user %s" % (user_profile_id,)) if uses_notification_bouncer(): try: send_notifications_to_bouncer(user_profile_id, apns_payload, gcm_payload) except requests.ConnectionError: def failure_processor(event: Dict[str, Any]) -> None: logger.warning( "Maximum retries exceeded for trigger:%s event:push_notification" % ( event['user_profile_id'])) retry_event('missedmessage_mobile_notifications', missed_message, failure_processor) return android_devices = list(PushDeviceToken.objects.filter(user=user_profile, kind=PushDeviceToken.GCM)) apple_devices = list(PushDeviceToken.objects.filter(user=user_profile, kind=PushDeviceToken.APNS)) if apple_devices: send_apple_push_notification(user_profile.id, apple_devices, apns_payload) if android_devices: send_android_push_notification(android_devices, gcm_payload)