fix(tracing): properly resolve when multiple trace agent url env vari…

…ables are used (backport #3686) (#3689)

This is an automatic backport of pull request #3686 done by [Mergify](https://mergify.com).


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ddtrace/bootstrap/sitecustomize.py

@@ -78,9 +78,6 @@ def update_patched_modules():
 try:
     from ddtrace import tracer
 
-    dd_hostname = os.getenv("DD_TRACE_AGENT_HOSTNAME")
-    hostname = os.getenv("DD_AGENT_HOST", dd_hostname)
-    port = os.getenv("DD_TRACE_AGENT_PORT")
     priority_sampling = os.getenv("DD_PRIORITY_SAMPLING")
     profiling = asbool(os.getenv("DD_PROFILING_ENABLED", False))
 
@@ -100,10 +97,6 @@ def update_patched_modules():
         trace_enabled = False
         opts["enabled"] = False
 
-    if hostname:
-        opts["hostname"] = hostname
-    if port:
-        opts["port"] = int(port)
     if priority_sampling:
         opts["priority_sampling"] = asbool(priority_sampling)
 

ddtrace/internal/agent.py

@@ -24,7 +24,7 @@
 
 def get_trace_hostname(default=DEFAULT_HOSTNAME):
     # type: (Union[T, str]) -> Union[T, str]
-    return os.environ.get("DD_AGENT_HOST", os.environ.get("DATADOG_TRACE_AGENT_HOSTNAME", default))
+    return os.environ.get("DD_AGENT_HOST", os.environ.get("DD_TRACE_AGENT_HOSTNAME", default))
 
 
 def get_stats_hostname(default=DEFAULT_HOSTNAME):

releasenotes/notes/fix-ddtrace-run-url-envs-087ab03d4f25a732.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    tracing: fix issue with ``ddtrace-run`` having the wrong priority order of tracer host/port/url env variable configuration.