mirror of
https://git.anonymousland.org/anonymousland/synapse-product.git
synced 2024-12-18 22:24:19 -05:00
0ec12a3753
Now that we wait for stream positions whenever we do a HTTP replication hit, we need to be less brutal in the case where we do timeout (as we have bugs around this).
451 lines
18 KiB
Python
451 lines
18 KiB
Python
# Copyright 2018 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 abc
|
|
import logging
|
|
import re
|
|
import urllib.parse
|
|
from inspect import signature
|
|
from typing import TYPE_CHECKING, Any, Awaitable, Callable, ClassVar, Dict, List, Tuple
|
|
|
|
from prometheus_client import Counter, Gauge
|
|
|
|
from twisted.internet.error import ConnectError, DNSLookupError
|
|
from twisted.web.server import Request
|
|
|
|
from synapse.api.errors import HttpResponseException, SynapseError
|
|
from synapse.http import RequestTimedOutError
|
|
from synapse.http.server import HttpServer
|
|
from synapse.http.servlet import parse_json_object_from_request
|
|
from synapse.http.site import SynapseRequest
|
|
from synapse.logging import opentracing
|
|
from synapse.logging.opentracing import trace_with_opname
|
|
from synapse.types import JsonDict
|
|
from synapse.util.caches.response_cache import ResponseCache
|
|
from synapse.util.cancellation import is_function_cancellable
|
|
from synapse.util.stringutils import random_string
|
|
|
|
if TYPE_CHECKING:
|
|
from synapse.server import HomeServer
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
_pending_outgoing_requests = Gauge(
|
|
"synapse_pending_outgoing_replication_requests",
|
|
"Number of active outgoing replication requests, by replication method name",
|
|
["name"],
|
|
)
|
|
|
|
_outgoing_request_counter = Counter(
|
|
"synapse_outgoing_replication_requests",
|
|
"Number of outgoing replication requests, by replication method name and result",
|
|
["name", "code"],
|
|
)
|
|
|
|
|
|
_STREAM_POSITION_KEY = "_INT_STREAM_POS"
|
|
|
|
|
|
class ReplicationEndpoint(metaclass=abc.ABCMeta):
|
|
"""Helper base class for defining new replication HTTP endpoints.
|
|
|
|
This creates an endpoint under `/_synapse/replication/:NAME/:PATH_ARGS..`
|
|
(with a `/:txn_id` suffix for cached requests), where NAME is a name,
|
|
PATH_ARGS are a tuple of parameters to be encoded in the URL.
|
|
|
|
For example, if `NAME` is "send_event" and `PATH_ARGS` is `("event_id",)`,
|
|
with `CACHE` set to true then this generates an endpoint:
|
|
|
|
/_synapse/replication/send_event/:event_id/:txn_id
|
|
|
|
For POST/PUT requests the payload is serialized to json and sent as the
|
|
body, while for GET requests the payload is added as query parameters. See
|
|
`_serialize_payload` for details.
|
|
|
|
Incoming requests are handled by overriding `_handle_request`. Servers
|
|
must call `register` to register the path with the HTTP server.
|
|
|
|
Requests can be sent by calling the client returned by `make_client`.
|
|
Requests are sent to master process by default, but can be sent to other
|
|
named processes by specifying an `instance_name` keyword argument.
|
|
|
|
Attributes:
|
|
NAME (str): A name for the endpoint, added to the path as well as used
|
|
in logging and metrics.
|
|
PATH_ARGS (tuple[str]): A list of parameters to be added to the path.
|
|
Adding parameters to the path (rather than payload) can make it
|
|
easier to follow along in the log files.
|
|
METHOD (str): The method of the HTTP request, defaults to POST. Can be
|
|
one of POST, PUT or GET. If GET then the payload is sent as query
|
|
parameters rather than a JSON body.
|
|
CACHE (bool): Whether server should cache the result of the request/
|
|
If true then transparently adds a txn_id to all requests, and
|
|
`_handle_request` must return a Deferred.
|
|
RETRY_ON_TIMEOUT(bool): Whether or not to retry the request when a 504
|
|
is received.
|
|
RETRY_ON_CONNECT_ERROR (bool): Whether or not to retry the request when
|
|
a connection error is received.
|
|
RETRY_ON_CONNECT_ERROR_ATTEMPTS (int): Number of attempts to retry when
|
|
receiving connection errors, each will backoff exponentially longer.
|
|
WAIT_FOR_STREAMS (bool): Whether to wait for replication streams to
|
|
catch up before processing the request and/or response. Defaults to
|
|
True.
|
|
"""
|
|
|
|
NAME: str = abc.abstractproperty() # type: ignore
|
|
PATH_ARGS: Tuple[str, ...] = abc.abstractproperty() # type: ignore
|
|
METHOD = "POST"
|
|
CACHE = True
|
|
RETRY_ON_TIMEOUT = True
|
|
RETRY_ON_CONNECT_ERROR = True
|
|
RETRY_ON_CONNECT_ERROR_ATTEMPTS = 5 # =63s (2^6-1)
|
|
|
|
WAIT_FOR_STREAMS: ClassVar[bool] = True
|
|
|
|
def __init__(self, hs: "HomeServer"):
|
|
if self.CACHE:
|
|
self.response_cache: ResponseCache[str] = ResponseCache(
|
|
hs.get_clock(), "repl." + self.NAME, timeout_ms=30 * 60 * 1000
|
|
)
|
|
|
|
# We reserve `instance_name` as a parameter to sending requests, so we
|
|
# assert here that sub classes don't try and use the name.
|
|
assert (
|
|
"instance_name" not in self.PATH_ARGS
|
|
), "`instance_name` is a reserved parameter name"
|
|
assert (
|
|
"instance_name"
|
|
not in signature(self.__class__._serialize_payload).parameters
|
|
), "`instance_name` is a reserved parameter name"
|
|
|
|
assert self.METHOD in ("PUT", "POST", "GET")
|
|
|
|
self._replication_secret = None
|
|
if hs.config.worker.worker_replication_secret:
|
|
self._replication_secret = hs.config.worker.worker_replication_secret
|
|
|
|
self._streams = hs.get_replication_command_handler().get_streams_to_replicate()
|
|
self._replication = hs.get_replication_data_handler()
|
|
self._instance_name = hs.get_instance_name()
|
|
|
|
def _check_auth(self, request: Request) -> None:
|
|
# Get the authorization header.
|
|
auth_headers = request.requestHeaders.getRawHeaders(b"Authorization")
|
|
|
|
if not auth_headers:
|
|
raise RuntimeError("Missing Authorization header.")
|
|
if len(auth_headers) > 1:
|
|
raise RuntimeError("Too many Authorization headers.")
|
|
parts = auth_headers[0].split(b" ")
|
|
if parts[0] == b"Bearer" and len(parts) == 2:
|
|
received_secret = parts[1].decode("ascii")
|
|
if self._replication_secret == received_secret:
|
|
# Success!
|
|
return
|
|
|
|
raise RuntimeError("Invalid Authorization header.")
|
|
|
|
@abc.abstractmethod
|
|
async def _serialize_payload(**kwargs) -> JsonDict:
|
|
"""Static method that is called when creating a request.
|
|
|
|
Concrete implementations should have explicit parameters (rather than
|
|
kwargs) so that an appropriate exception is raised if the client is
|
|
called with unexpected parameters. All PATH_ARGS must appear in
|
|
argument list.
|
|
|
|
Returns:
|
|
If POST/PUT request then dictionary must be JSON serialisable,
|
|
otherwise must be appropriate for adding as query args.
|
|
"""
|
|
return {}
|
|
|
|
@abc.abstractmethod
|
|
async def _handle_request(
|
|
self, request: Request, content: JsonDict, **kwargs: Any
|
|
) -> Tuple[int, JsonDict]:
|
|
"""Handle incoming request.
|
|
|
|
This is called with the request object and PATH_ARGS.
|
|
|
|
Returns:
|
|
HTTP status code and a JSON serialisable dict to be used as response
|
|
body of request.
|
|
"""
|
|
|
|
@classmethod
|
|
def make_client(cls, hs: "HomeServer") -> Callable:
|
|
"""Create a client that makes requests.
|
|
|
|
Returns a callable that accepts the same parameters as
|
|
`_serialize_payload`, and also accepts an optional `instance_name`
|
|
parameter to specify which instance to hit (the instance must be in
|
|
the `instance_map` config).
|
|
"""
|
|
clock = hs.get_clock()
|
|
client = hs.get_simple_http_client()
|
|
local_instance_name = hs.get_instance_name()
|
|
|
|
# The value of these option should match the replication listener settings
|
|
master_host = hs.config.worker.worker_replication_host
|
|
master_port = hs.config.worker.worker_replication_http_port
|
|
master_tls = hs.config.worker.worker_replication_http_tls
|
|
|
|
instance_map = hs.config.worker.instance_map
|
|
|
|
outgoing_gauge = _pending_outgoing_requests.labels(cls.NAME)
|
|
|
|
replication_secret = None
|
|
if hs.config.worker.worker_replication_secret:
|
|
replication_secret = hs.config.worker.worker_replication_secret.encode(
|
|
"ascii"
|
|
)
|
|
|
|
@trace_with_opname("outgoing_replication_request")
|
|
async def send_request(*, instance_name: str = "master", **kwargs: Any) -> Any:
|
|
# We have to pull these out here to avoid circular dependencies...
|
|
streams = hs.get_replication_command_handler().get_streams_to_replicate()
|
|
replication = hs.get_replication_data_handler()
|
|
|
|
with outgoing_gauge.track_inprogress():
|
|
if instance_name == local_instance_name:
|
|
raise Exception("Trying to send HTTP request to self")
|
|
if instance_name == "master":
|
|
host = master_host
|
|
port = master_port
|
|
tls = master_tls
|
|
elif instance_name in instance_map:
|
|
host = instance_map[instance_name].host
|
|
port = instance_map[instance_name].port
|
|
tls = instance_map[instance_name].tls
|
|
else:
|
|
raise Exception(
|
|
"Instance %r not in 'instance_map' config" % (instance_name,)
|
|
)
|
|
|
|
data = await cls._serialize_payload(**kwargs)
|
|
|
|
if cls.METHOD != "GET" and cls.WAIT_FOR_STREAMS:
|
|
# Include the current stream positions that we write to. We
|
|
# don't do this for GETs as they don't have a body, and we
|
|
# generally assume that a GET won't rely on data we have
|
|
# written.
|
|
if _STREAM_POSITION_KEY in data:
|
|
raise Exception(
|
|
"data to send contains %r key", _STREAM_POSITION_KEY
|
|
)
|
|
|
|
data[_STREAM_POSITION_KEY] = {
|
|
"streams": {
|
|
stream.NAME: stream.current_token(local_instance_name)
|
|
for stream in streams
|
|
},
|
|
"instance_name": local_instance_name,
|
|
}
|
|
|
|
url_args = [
|
|
urllib.parse.quote(kwargs[name], safe="") for name in cls.PATH_ARGS
|
|
]
|
|
|
|
if cls.CACHE:
|
|
txn_id = random_string(10)
|
|
url_args.append(txn_id)
|
|
|
|
if cls.METHOD == "POST":
|
|
request_func: Callable[
|
|
..., Awaitable[Any]
|
|
] = client.post_json_get_json
|
|
elif cls.METHOD == "PUT":
|
|
request_func = client.put_json
|
|
elif cls.METHOD == "GET":
|
|
request_func = client.get_json
|
|
else:
|
|
# We have already asserted in the constructor that a
|
|
# compatible was picked, but lets be paranoid.
|
|
raise Exception(
|
|
"Unknown METHOD on %s replication endpoint" % (cls.NAME,)
|
|
)
|
|
|
|
# Here the protocol is hard coded to be http by default or https in case the replication
|
|
# port is set to have tls true.
|
|
scheme = "https" if tls else "http"
|
|
uri = "%s://%s:%s/_synapse/replication/%s/%s" % (
|
|
scheme,
|
|
host,
|
|
port,
|
|
cls.NAME,
|
|
"/".join(url_args),
|
|
)
|
|
|
|
headers: Dict[bytes, List[bytes]] = {}
|
|
# Add an authorization header, if configured.
|
|
if replication_secret:
|
|
headers[b"Authorization"] = [b"Bearer " + replication_secret]
|
|
opentracing.inject_header_dict(headers, check_destination=False)
|
|
|
|
try:
|
|
# Keep track of attempts made so we can bail if we don't manage to
|
|
# connect to the target after N tries.
|
|
attempts = 0
|
|
# We keep retrying the same request for timeouts. This is so that we
|
|
# have a good idea that the request has either succeeded or failed
|
|
# on the master, and so whether we should clean up or not.
|
|
while True:
|
|
try:
|
|
result = await request_func(uri, data, headers=headers)
|
|
break
|
|
except RequestTimedOutError:
|
|
if not cls.RETRY_ON_TIMEOUT:
|
|
raise
|
|
|
|
logger.warning("%s request timed out; retrying", cls.NAME)
|
|
|
|
# If we timed out we probably don't need to worry about backing
|
|
# off too much, but lets just wait a little anyway.
|
|
await clock.sleep(1)
|
|
except (ConnectError, DNSLookupError) as e:
|
|
if not cls.RETRY_ON_CONNECT_ERROR:
|
|
raise
|
|
if attempts > cls.RETRY_ON_CONNECT_ERROR_ATTEMPTS:
|
|
raise
|
|
|
|
delay = 2**attempts
|
|
logger.warning(
|
|
"%s request connection failed; retrying in %ds: %r",
|
|
cls.NAME,
|
|
delay,
|
|
e,
|
|
)
|
|
|
|
await clock.sleep(delay)
|
|
attempts += 1
|
|
except HttpResponseException as e:
|
|
# We convert to SynapseError as we know that it was a SynapseError
|
|
# on the main process that we should send to the client. (And
|
|
# importantly, not stack traces everywhere)
|
|
_outgoing_request_counter.labels(cls.NAME, e.code).inc()
|
|
raise e.to_synapse_error()
|
|
except Exception as e:
|
|
_outgoing_request_counter.labels(cls.NAME, "ERR").inc()
|
|
raise SynapseError(
|
|
502, f"Failed to talk to {instance_name} process"
|
|
) from e
|
|
|
|
_outgoing_request_counter.labels(cls.NAME, 200).inc()
|
|
|
|
# Wait on any streams that the remote may have written to.
|
|
for stream_name, position in result.get(
|
|
_STREAM_POSITION_KEY, {}
|
|
).items():
|
|
await replication.wait_for_stream_position(
|
|
instance_name=instance_name,
|
|
stream_name=stream_name,
|
|
position=position,
|
|
)
|
|
|
|
return result
|
|
|
|
return send_request
|
|
|
|
def register(self, http_server: HttpServer) -> None:
|
|
"""Called by the server to register this as a handler to the
|
|
appropriate path.
|
|
"""
|
|
|
|
url_args = list(self.PATH_ARGS)
|
|
method = self.METHOD
|
|
|
|
if self.CACHE and is_function_cancellable(self._handle_request):
|
|
raise Exception(
|
|
f"{self.__class__.__name__} has been marked as cancellable, but CACHE "
|
|
"is set. The cancellable flag would have no effect."
|
|
)
|
|
|
|
if self.CACHE:
|
|
url_args.append("txn_id")
|
|
|
|
args = "/".join("(?P<%s>[^/]+)" % (arg,) for arg in url_args)
|
|
pattern = re.compile("^/_synapse/replication/%s/%s$" % (self.NAME, args))
|
|
|
|
http_server.register_paths(
|
|
method,
|
|
[pattern],
|
|
self._check_auth_and_handle,
|
|
self.__class__.__name__,
|
|
)
|
|
|
|
async def _check_auth_and_handle(
|
|
self, request: SynapseRequest, **kwargs: Any
|
|
) -> Tuple[int, JsonDict]:
|
|
"""Called on new incoming requests when caching is enabled. Checks
|
|
if there is a cached response for the request and returns that,
|
|
otherwise calls `_handle_request` and caches its response.
|
|
"""
|
|
# We just use the txn_id here, but we probably also want to use the
|
|
# other PATH_ARGS as well.
|
|
|
|
# Check the authorization headers before handling the request.
|
|
if self._replication_secret:
|
|
self._check_auth(request)
|
|
|
|
if self.METHOD == "GET":
|
|
# GET APIs always have an empty body.
|
|
content = {}
|
|
else:
|
|
content = parse_json_object_from_request(request)
|
|
|
|
# Wait on any streams that the remote may have written to.
|
|
for stream_name, position in content.get(_STREAM_POSITION_KEY, {"streams": {}})[
|
|
"streams"
|
|
].items():
|
|
await self._replication.wait_for_stream_position(
|
|
instance_name=content[_STREAM_POSITION_KEY]["instance_name"],
|
|
stream_name=stream_name,
|
|
position=position,
|
|
)
|
|
|
|
if self.CACHE:
|
|
txn_id = kwargs.pop("txn_id")
|
|
|
|
# We ignore the `@cancellable` flag, since cancellation wouldn't interupt
|
|
# `_handle_request` and `ResponseCache` does not handle cancellation
|
|
# correctly yet. In particular, there may be issues to do with logging
|
|
# context lifetimes.
|
|
|
|
code, response = await self.response_cache.wrap(
|
|
txn_id, self._handle_request, request, content, **kwargs
|
|
)
|
|
else:
|
|
# The `@cancellable` decorator may be applied to `_handle_request`. But we
|
|
# told `HttpServer.register_paths` that our handler is `_check_auth_and_handle`,
|
|
# so we have to set up the cancellable flag ourselves.
|
|
request.is_render_cancellable = is_function_cancellable(
|
|
self._handle_request
|
|
)
|
|
|
|
code, response = await self._handle_request(request, content, **kwargs)
|
|
|
|
# Return streams we may have written to in the course of processing this
|
|
# request.
|
|
if _STREAM_POSITION_KEY in response:
|
|
raise Exception("data to send contains %r key", _STREAM_POSITION_KEY)
|
|
|
|
if self.WAIT_FOR_STREAMS:
|
|
response[_STREAM_POSITION_KEY] = {
|
|
stream.NAME: stream.current_token(self._instance_name)
|
|
for stream in self._streams
|
|
}
|
|
|
|
return code, response
|