Add instance name to RDATA/POSITION commands (#7364)

This is primarily for allowing us to send those commands from workers, but for now simply allows us to ignore echoed RDATA/POSITION commands that we sent (we get echoes of sent commands when using redis). Currently we log a WARNING on the master process every time we receive an echoed RDATA.

synapse/logging/opentracing.py

@@ -171,7 +171,7 @@ import logging
 import re
 import types
 from functools import wraps
-from typing import Dict
+from typing import TYPE_CHECKING, Dict
 
 from canonicaljson import json
 
@@ -179,6 +179,9 @@ from twisted.internet import defer
 
 from synapse.config import ConfigError
 
+if TYPE_CHECKING:
+    from synapse.server import HomeServer
+
 # Helper class
 
 
@@ -297,14 +300,11 @@ def _noop_context_manager(*args, **kwargs):
 # Setup
 
 
-def init_tracer(config):
+def init_tracer(hs: "HomeServer"):
     """Set the whitelists and initialise the JaegerClient tracer
-
-    Args:
-        config (HomeserverConfig): The config used by the homeserver
     """
     global opentracing
-    if not config.opentracer_enabled:
+    if not hs.config.opentracer_enabled:
         # We don't have a tracer
         opentracing = None
         return
@@ -315,18 +315,15 @@ def init_tracer(config):
             "installed."
         )
 
-    # Include the worker name
-    name = config.worker_name if config.worker_name else "master"
-
     # Pull out the jaeger config if it was given. Otherwise set it to something sensible.
     # See https://github.com/jaegertracing/jaeger-client-python/blob/master/jaeger_client/config.py
 
-    set_homeserver_whitelist(config.opentracer_whitelist)
+    set_homeserver_whitelist(hs.config.opentracer_whitelist)
 
     JaegerConfig(
-        config=config.jaeger_config,
-        service_name="{} {}".format(config.server_name, name),
-        scope_manager=LogContextScopeManager(config),
+        config=hs.config.jaeger_config,
+        service_name="{} {}".format(hs.config.server_name, hs.get_instance_name()),
+        scope_manager=LogContextScopeManager(hs.config),
     ).initialize_tracer()