Richard van der Hoff
parent
7871146667
commit
fe212bbe4a
|
|
@ -13,15 +13,8 @@
|
|||
# See the License for the specific language governing permissions and
|
||||
# limitations under the License.
|
||||
import logging
|
||||
import random
|
||||
import re
|
||||
|
||||
from twisted.internet import defer
|
||||
from twisted.internet.endpoints import HostnameEndpoint, wrapClientTLS
|
||||
from twisted.internet.error import ConnectError
|
||||
|
||||
from synapse.http.federation.srv_resolver import Server, resolve_service
|
||||
|
||||
logger = logging.getLogger(__name__)
|
||||
|
||||
|
||||
|
|
@ -88,140 +81,3 @@ def parse_and_validate_server_name(server_name):
|
|||
))
|
||||
|
||||
return host, port
|
||||
|
||||
|
||||
def matrix_federation_endpoint(reactor, destination, tls_client_options_factory=None,
|
||||
timeout=None):
|
||||
"""Construct an endpoint for the given matrix destination.
|
||||
|
||||
Args:
|
||||
reactor: Twisted reactor.
|
||||
destination (unicode): The name of the server to connect to.
|
||||
tls_client_options_factory
|
||||
(synapse.crypto.context_factory.ClientTLSOptionsFactory):
|
||||
Factory which generates TLS options for client connections.
|
||||
timeout (int): connection timeout in seconds
|
||||
"""
|
||||
|
||||
domain, port = parse_server_name(destination)
|
||||
|
||||
endpoint_kw_args = {}
|
||||
|
||||
if timeout is not None:
|
||||
endpoint_kw_args.update(timeout=timeout)
|
||||
|
||||
if tls_client_options_factory is None:
|
||||
transport_endpoint = HostnameEndpoint
|
||||
default_port = 8008
|
||||
else:
|
||||
# the SNI string should be the same as the Host header, minus the port.
|
||||
# as per https://github.com/matrix-org/synapse/issues/2525#issuecomment-336896777,
|
||||
# the Host header and SNI should therefore be the server_name of the remote
|
||||
# server.
|
||||
tls_options = tls_client_options_factory.get_options(domain)
|
||||
|
||||
def transport_endpoint(reactor, host, port, timeout):
|
||||
return wrapClientTLS(
|
||||
tls_options,
|
||||
HostnameEndpoint(reactor, host, port, timeout=timeout),
|
||||
)
|
||||
default_port = 8448
|
||||
|
||||
if port is None:
|
||||
return SRVClientEndpoint(
|
||||
reactor, "matrix", domain, protocol="tcp",
|
||||
default_port=default_port, endpoint=transport_endpoint,
|
||||
endpoint_kw_args=endpoint_kw_args
|
||||
)
|
||||
else:
|
||||
return transport_endpoint(
|
||||
reactor, domain, port, **endpoint_kw_args
|
||||
)
|
||||
|
||||
|
||||
class SRVClientEndpoint(object):
|
||||
"""An endpoint which looks up SRV records for a service.
|
||||
Cycles through the list of servers starting with each call to connect
|
||||
picking the next server.
|
||||
Implements twisted.internet.interfaces.IStreamClientEndpoint.
|
||||
"""
|
||||
|
||||
def __init__(self, reactor, service, domain, protocol="tcp",
|
||||
default_port=None, endpoint=HostnameEndpoint,
|
||||
endpoint_kw_args={}):
|
||||
self.reactor = reactor
|
||||
self.service_name = "_%s._%s.%s" % (service, protocol, domain)
|
||||
|
||||
if default_port is not None:
|
||||
self.default_server = Server(
|
||||
host=domain,
|
||||
port=default_port,
|
||||
)
|
||||
else:
|
||||
self.default_server = None
|
||||
|
||||
self.endpoint = endpoint
|
||||
self.endpoint_kw_args = endpoint_kw_args
|
||||
|
||||
self.servers = None
|
||||
self.used_servers = None
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def fetch_servers(self):
|
||||
self.used_servers = []
|
||||
self.servers = yield resolve_service(self.service_name)
|
||||
|
||||
def pick_server(self):
|
||||
if not self.servers:
|
||||
if self.used_servers:
|
||||
self.servers = self.used_servers
|
||||
self.used_servers = []
|
||||
self.servers.sort()
|
||||
elif self.default_server:
|
||||
return self.default_server
|
||||
else:
|
||||
raise ConnectError(
|
||||
"No server available for %s" % self.service_name
|
||||
)
|
||||
|
||||
# look for all servers with the same priority
|
||||
min_priority = self.servers[0].priority
|
||||
weight_indexes = list(
|
||||
(index, server.weight + 1)
|
||||
for index, server in enumerate(self.servers)
|
||||
if server.priority == min_priority
|
||||
)
|
||||
|
||||
total_weight = sum(weight for index, weight in weight_indexes)
|
||||
target_weight = random.randint(0, total_weight)
|
||||
for index, weight in weight_indexes:
|
||||
target_weight -= weight
|
||||
if target_weight <= 0:
|
||||
server = self.servers[index]
|
||||
# XXX: this looks totally dubious:
|
||||
#
|
||||
# (a) we never reuse a server until we have been through
|
||||
# all of the servers at the same priority, so if the
|
||||
# weights are A: 100, B:1, we always do ABABAB instead of
|
||||
# AAAA...AAAB (approximately).
|
||||
#
|
||||
# (b) After using all the servers at the lowest priority,
|
||||
# we move onto the next priority. We should only use the
|
||||
# second priority if servers at the top priority are
|
||||
# unreachable.
|
||||
#
|
||||
del self.servers[index]
|
||||
self.used_servers.append(server)
|
||||
return server
|
||||
|
||||
@defer.inlineCallbacks
|
||||
def connect(self, protocolFactory):
|
||||
if self.servers is None:
|
||||
yield self.fetch_servers()
|
||||
server = self.pick_server()
|
||||
logger.info("Connecting to %s:%s", server.host, server.port)
|
||||
endpoint = self.endpoint(
|
||||
self.reactor, server.host, server.port, **self.endpoint_kw_args
|
||||
)
|
||||
connection = yield endpoint.connect(protocolFactory)
|
||||
defer.returnValue(connection)
|
||||
|
|
|
|||
|
|
@ -152,6 +152,5 @@ def resolve_service(service_name, dns_client=client, cache=SERVER_CACHE, clock=t
|
|||
expires=int(clock.time()) + answer.ttl,
|
||||
))
|
||||
|
||||
servers.sort() # FIXME: get rid of this (it's broken by the attrs change)
|
||||
cache[service_name] = list(servers)
|
||||
defer.returnValue(servers)
|
||||
|
|
|
|||
Loading…
Reference in New Issue