Use the BaseReporter super-class for _WrappedRustReporter. (#10799)

This fixes mypy errors with jaeger-client >= 4.7.0 and should be a no-op
for versions before that.

changelog.d/10799.misc

@@ -0,0 +1 @@
+Add a max version for the `jaeger-client` dependency for an incompatibility with the rust reporter.

synapse/logging/opentracing.py

@@ -236,8 +236,17 @@ class _DummyTagNames:
 try:
  from rust_python_jaeger_reporter import Reporter
 
+ # jaeger-client 4.7.0 requires that reporters inherit from BaseReporter, which
+ # didn't exist before that version.
+ try:
+ from jaeger_client.reporter import BaseReporter
+ except ImportError:
+
+ class BaseReporter: # type: ignore[no-redef]
+ pass
+
  @attr.s(slots=True, frozen=True)
- class _WrappedRustReporter:
+ class _WrappedRustReporter(BaseReporter):
  """Wrap the reporter to ensure `report_span` never throws."""
 
  _reporter = attr.ib(type=Reporter, default=attr.Factory(Reporter))
@@ -382,6 +391,7 @@ def init_tracer(hs: "HomeServer"):
  # If we have the rust jaeger reporter available let's use that.
  if RustReporter:
  logger.info("Using rust_python_jaeger_reporter library")
+ assert config.sampler is not None
  tracer = config.create_tracer(RustReporter(), config.sampler)
  opentracing.set_global_tracer(tracer)
  else: