forked-synapse/synapse/config/tracer.py
David Robertson 313581e4e9
Use importlib.metadata to read requirements (#12088)
* Pull runtime dep checks into their own module
* Reimplement `check_requirements` using `importlib`

I've tried to make this clearer. We start by working out which of
Synapse's requirements we need to be installed here and now. I was
surprised that there wasn't an easier way to see which packages were
installed by a given extra.

I've pulled out the error messages into functions that deal with "is
this for an extra or not". And I've rearranged the loop over two
different sets of requirements into one loop with a "must be instaled"
flag.

I hope you agree that this is clearer.

* Test cases
2022-03-01 17:44:41 +00:00

117 lines
4.3 KiB
Python

# Copyright 2019 The Matrix.org Foundation C.I.C.d
#
# 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.
from typing import Set
from synapse.util.check_dependencies import DependencyException, check_requirements
from ._base import Config, ConfigError
class TracerConfig(Config):
section = "tracing"
def read_config(self, config, **kwargs):
opentracing_config = config.get("opentracing")
if opentracing_config is None:
opentracing_config = {}
self.opentracer_enabled = opentracing_config.get("enabled", False)
self.jaeger_config = opentracing_config.get(
"jaeger_config",
{"sampler": {"type": "const", "param": 1}, "logging": False},
)
self.force_tracing_for_users: Set[str] = set()
if not self.opentracer_enabled:
return
try:
check_requirements("opentracing")
except DependencyException as e:
raise ConfigError(
e.message # noqa: B306, DependencyException.message is a property
)
# The tracer is enabled so sanitize the config
self.opentracer_whitelist = opentracing_config.get("homeserver_whitelist", [])
if not isinstance(self.opentracer_whitelist, list):
raise ConfigError("Tracer homeserver_whitelist config is malformed")
force_tracing_for_users = opentracing_config.get("force_tracing_for_users", [])
if not isinstance(force_tracing_for_users, list):
raise ConfigError(
"Expected a list", ("opentracing", "force_tracing_for_users")
)
for i, u in enumerate(force_tracing_for_users):
if not isinstance(u, str):
raise ConfigError(
"Expected a string",
("opentracing", "force_tracing_for_users", f"index {i}"),
)
self.force_tracing_for_users.add(u)
def generate_config_section(cls, **kwargs):
return """\
## Opentracing ##
# These settings enable opentracing, which implements distributed tracing.
# This allows you to observe the causal chains of events across servers
# including requests, key lookups etc., across any server running
# synapse or any other other services which supports opentracing
# (specifically those implemented with Jaeger).
#
opentracing:
# tracing is disabled by default. Uncomment the following line to enable it.
#
#enabled: true
# The list of homeservers we wish to send and receive span contexts and span baggage.
# See https://matrix-org.github.io/synapse/latest/opentracing.html.
#
# This is a list of regexes which are matched against the server_name of the
# homeserver.
#
# By default, it is empty, so no servers are matched.
#
#homeserver_whitelist:
# - ".*"
# A list of the matrix IDs of users whose requests will always be traced,
# even if the tracing system would otherwise drop the traces due to
# probabilistic sampling.
#
# By default, the list is empty.
#
#force_tracing_for_users:
# - "@user1:server_name"
# - "@user2:server_name"
# Jaeger can be configured to sample traces at different rates.
# All configuration options provided by Jaeger can be set here.
# Jaeger's configuration is mostly related to trace sampling which
# is documented here:
# https://www.jaegertracing.io/docs/latest/sampling/.
#
#jaeger_config:
# sampler:
# type: const
# param: 1
# logging:
# false
"""