forked-synapse/synapse/replication/tcp/streams/_base.py
Richard van der Hoff 67ff7b8ba0
Improve type checking in replication.tcp.Stream (#7291)
The general idea here is to get rid of the type: ignore annotations on all of the current_token and update_function assignments, which would have caught #7290.

After a bit of experimentation, it seems like the least-awful way to do this is to pass the offending functions in as parameters to the Stream constructor. Unfortunately that means that the concrete implementations no longer have the same constructor signature as Stream itself, which means that it gets hard to correctly annotate STREAMS_MAP.

I've also introduced a couple of new types, to take out some duplication.
2020-04-17 14:49:55 +01:00

542 lines
16 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2017 Vector Creations Ltd
# 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.
import logging
from collections import namedtuple
from typing import Any, Awaitable, Callable, Iterable, List, Optional, Tuple
import attr
from synapse.replication.http.streams import ReplicationGetStreamUpdates
logger = logging.getLogger(__name__)
MAX_EVENTS_BEHIND = 500000
# Some type aliases to make things a bit easier.
# A stream position token
Token = int
# The type of a stream update row, after JSON deserialisation, but before
# parsing with Stream.parse_row (which turns it into a `ROW_TYPE`). Normally it's
# just a row from a database query, though this is dependent on the stream in question.
#
StreamRow = Tuple
# The type returned by the update_function of a stream, as well as get_updates(),
# get_updates_since, etc.
#
# It consists of a triplet `(updates, new_last_token, limited)`, where:
# * `updates` is a list of `(token, row)` entries.
# * `new_last_token` is the new position in stream.
# * `limited` is whether there are more updates to fetch.
#
StreamUpdateResult = Tuple[List[Tuple[Token, StreamRow]], Token, bool]
# The type of an update_function for a stream
#
# The arguments are:
#
# * from_token: the previous stream token: the starting point for fetching the
# updates
# * to_token: the new stream token: the point to get updates up to
# * limit: the maximum number of rows to return
#
UpdateFunction = Callable[[Token, Token, int], Awaitable[StreamUpdateResult]]
class Stream(object):
"""Base class for the streams.
Provides a `get_updates()` function that returns new updates since the last
time it was called.
"""
NAME = None # type: str # The name of the stream
# The type of the row. Used by the default impl of parse_row.
ROW_TYPE = None # type: Any
@classmethod
def parse_row(cls, row: StreamRow):
"""Parse a row received over replication
By default, assumes that the row data is an array object and passes its contents
to the constructor of the ROW_TYPE for this stream.
Args:
row: row data from the incoming RDATA command, after json decoding
Returns:
ROW_TYPE object for this stream
"""
return cls.ROW_TYPE(*row)
def __init__(
self,
current_token_function: Callable[[], Token],
update_function: UpdateFunction,
):
"""Instantiate a Stream
current_token_function and update_function are callbacks which should be
implemented by subclasses.
current_token_function is called to get the current token of the underlying
stream.
update_function is called to get updates for this stream between a pair of
stream tokens. See the UpdateFunction type definition for more info.
Args:
current_token_function: callback to get the current token, as above
update_function: callback go get stream updates, as above
"""
self.current_token = current_token_function
self.update_function = update_function
# The token from which we last asked for updates
self.last_token = self.current_token()
def discard_updates_and_advance(self):
"""Called when the stream should advance but the updates would be discarded,
e.g. when there are no currently connected workers.
"""
self.last_token = self.current_token()
async def get_updates(self) -> StreamUpdateResult:
"""Gets all updates since the last time this function was called (or
since the stream was constructed if it hadn't been called before).
Returns:
A triplet `(updates, new_last_token, limited)`, where `updates` is
a list of `(token, row)` entries, `new_last_token` is the new
position in stream, and `limited` is whether there are more updates
to fetch.
"""
current_token = self.current_token()
updates, current_token, limited = await self.get_updates_since(
self.last_token, current_token
)
self.last_token = current_token
return updates, current_token, limited
async def get_updates_since(
self, from_token: Token, upto_token: Token, limit: int = 100
) -> StreamUpdateResult:
"""Like get_updates except allows specifying from when we should
stream updates
Returns:
A triplet `(updates, new_last_token, limited)`, where `updates` is
a list of `(token, row)` entries, `new_last_token` is the new
position in stream, and `limited` is whether there are more updates
to fetch.
"""
from_token = int(from_token)
if from_token == upto_token:
return [], upto_token, False
updates, upto_token, limited = await self.update_function(
from_token, upto_token, limit,
)
return updates, upto_token, limited
def db_query_to_update_function(
query_function: Callable[[Token, Token, int], Awaitable[Iterable[tuple]]]
) -> UpdateFunction:
"""Wraps a db query function which returns a list of rows to make it
suitable for use as an `update_function` for the Stream class
"""
async def update_function(from_token, upto_token, limit):
rows = await query_function(from_token, upto_token, limit)
updates = [(row[0], row[1:]) for row in rows]
limited = False
if len(updates) == limit:
upto_token = updates[-1][0]
limited = True
assert len(updates) <= limit
return updates, upto_token, limited
return update_function
def make_http_update_function(hs, stream_name: str) -> UpdateFunction:
"""Makes a suitable function for use as an `update_function` that queries
the master process for updates.
"""
client = ReplicationGetStreamUpdates.make_client(hs)
async def update_function(
from_token: int, upto_token: int, limit: int
) -> StreamUpdateResult:
result = await client(
stream_name=stream_name,
from_token=from_token,
upto_token=upto_token,
limit=limit,
)
return result["updates"], result["upto_token"], result["limited"]
return update_function
class BackfillStream(Stream):
"""We fetched some old events and either we had never seen that event before
or it went from being an outlier to not.
"""
BackfillStreamRow = namedtuple(
"BackfillStreamRow",
(
"event_id", # str
"room_id", # str
"type", # str
"state_key", # str, optional
"redacts", # str, optional
"relates_to", # str, optional
),
)
NAME = "backfill"
ROW_TYPE = BackfillStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_current_backfill_token,
db_query_to_update_function(store.get_all_new_backfill_event_rows),
)
class PresenceStream(Stream):
PresenceStreamRow = namedtuple(
"PresenceStreamRow",
(
"user_id", # str
"state", # str
"last_active_ts", # int
"last_federation_update_ts", # int
"last_user_sync_ts", # int
"status_msg", # str
"currently_active", # bool
),
)
NAME = "presence"
ROW_TYPE = PresenceStreamRow
def __init__(self, hs):
store = hs.get_datastore()
if hs.config.worker_app is None:
# on the master, query the presence handler
presence_handler = hs.get_presence_handler()
update_function = db_query_to_update_function(
presence_handler.get_all_presence_updates
)
else:
# Query master process
update_function = make_http_update_function(hs, self.NAME)
super().__init__(store.get_current_presence_token, update_function)
class TypingStream(Stream):
TypingStreamRow = namedtuple(
"TypingStreamRow", ("room_id", "user_ids") # str # list(str)
)
NAME = "typing"
ROW_TYPE = TypingStreamRow
def __init__(self, hs):
typing_handler = hs.get_typing_handler()
if hs.config.worker_app is None:
# on the master, query the typing handler
update_function = db_query_to_update_function(
typing_handler.get_all_typing_updates
)
else:
# Query master process
update_function = make_http_update_function(hs, self.NAME)
super().__init__(typing_handler.get_current_token, update_function)
class ReceiptsStream(Stream):
ReceiptsStreamRow = namedtuple(
"ReceiptsStreamRow",
(
"room_id", # str
"receipt_type", # str
"user_id", # str
"event_id", # str
"data", # dict
),
)
NAME = "receipts"
ROW_TYPE = ReceiptsStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_max_receipt_stream_id,
db_query_to_update_function(store.get_all_updated_receipts),
)
class PushRulesStream(Stream):
"""A user has changed their push rules
"""
PushRulesStreamRow = namedtuple("PushRulesStreamRow", ("user_id",)) # str
NAME = "push_rules"
ROW_TYPE = PushRulesStreamRow
def __init__(self, hs):
self.store = hs.get_datastore()
super(PushRulesStream, self).__init__(
self._current_token, self._update_function
)
def _current_token(self) -> int:
push_rules_token, _ = self.store.get_push_rules_stream_token()
return push_rules_token
async def _update_function(self, from_token: Token, to_token: Token, limit: int):
rows = await self.store.get_all_push_rule_updates(from_token, to_token, limit)
limited = False
if len(rows) == limit:
to_token = rows[-1][0]
limited = True
return [(row[0], (row[2],)) for row in rows], to_token, limited
class PushersStream(Stream):
"""A user has added/changed/removed a pusher
"""
PushersStreamRow = namedtuple(
"PushersStreamRow",
("user_id", "app_id", "pushkey", "deleted"), # str # str # str # bool
)
NAME = "pushers"
ROW_TYPE = PushersStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_pushers_stream_token,
db_query_to_update_function(store.get_all_updated_pushers_rows),
)
class CachesStream(Stream):
"""A cache was invalidated on the master and no other stream would invalidate
the cache on the workers
"""
@attr.s
class CachesStreamRow:
"""Stream to inform workers they should invalidate their cache.
Attributes:
cache_func: Name of the cached function.
keys: The entry in the cache to invalidate. If None then will
invalidate all.
invalidation_ts: Timestamp of when the invalidation took place.
"""
cache_func = attr.ib(type=str)
keys = attr.ib(type=Optional[List[Any]])
invalidation_ts = attr.ib(type=int)
NAME = "caches"
ROW_TYPE = CachesStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_cache_stream_token,
db_query_to_update_function(store.get_all_updated_caches),
)
class PublicRoomsStream(Stream):
"""The public rooms list changed
"""
PublicRoomsStreamRow = namedtuple(
"PublicRoomsStreamRow",
(
"room_id", # str
"visibility", # str
"appservice_id", # str, optional
"network_id", # str, optional
),
)
NAME = "public_rooms"
ROW_TYPE = PublicRoomsStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_current_public_room_stream_id,
db_query_to_update_function(store.get_all_new_public_rooms),
)
class DeviceListsStream(Stream):
"""Either a user has updated their devices or a remote server needs to be
told about a device update.
"""
@attr.s
class DeviceListsStreamRow:
entity = attr.ib(type=str)
NAME = "device_lists"
ROW_TYPE = DeviceListsStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_device_stream_token,
db_query_to_update_function(store.get_all_device_list_changes_for_remotes),
)
class ToDeviceStream(Stream):
"""New to_device messages for a client
"""
ToDeviceStreamRow = namedtuple("ToDeviceStreamRow", ("entity",)) # str
NAME = "to_device"
ROW_TYPE = ToDeviceStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_to_device_stream_token,
db_query_to_update_function(store.get_all_new_device_messages),
)
class TagAccountDataStream(Stream):
"""Someone added/removed a tag for a room
"""
TagAccountDataStreamRow = namedtuple(
"TagAccountDataStreamRow", ("user_id", "room_id", "data") # str # str # dict
)
NAME = "tag_account_data"
ROW_TYPE = TagAccountDataStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_max_account_data_stream_id,
db_query_to_update_function(store.get_all_updated_tags),
)
class AccountDataStream(Stream):
"""Global or per room account data was changed
"""
AccountDataStreamRow = namedtuple(
"AccountDataStream", ("user_id", "room_id", "data_type") # str # str # str
)
NAME = "account_data"
ROW_TYPE = AccountDataStreamRow
def __init__(self, hs):
self.store = hs.get_datastore()
super().__init__(
self.store.get_max_account_data_stream_id,
db_query_to_update_function(self._update_function),
)
async def _update_function(self, from_token, to_token, limit):
global_results, room_results = await self.store.get_all_updated_account_data(
from_token, from_token, to_token, limit
)
results = list(room_results)
results.extend(
(stream_id, user_id, None, account_data_type)
for stream_id, user_id, account_data_type in global_results
)
return results
class GroupServerStream(Stream):
GroupsStreamRow = namedtuple(
"GroupsStreamRow",
("group_id", "user_id", "type", "content"), # str # str # str # dict
)
NAME = "groups"
ROW_TYPE = GroupsStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_group_stream_token,
db_query_to_update_function(store.get_all_groups_changes),
)
class UserSignatureStream(Stream):
"""A user has signed their own device with their user-signing key
"""
UserSignatureStreamRow = namedtuple("UserSignatureStreamRow", ("user_id")) # str
NAME = "user_signature"
ROW_TYPE = UserSignatureStreamRow
def __init__(self, hs):
store = hs.get_datastore()
super().__init__(
store.get_device_stream_token,
db_query_to_update_function(
store.get_all_user_signature_changes_for_remotes
),
)