fix(tracer): add extra service names for all spans [backport 3.10]

ddtrace/_trace/processor/__init__.py

@@ -394,6 +394,11 @@ def on_span_finish(self, span: Span) -> None:
                         log.error("error applying processor %r", tp, exc_info=True)
 
                 self._queue_span_count_metrics("spans_finished", "integration_name")
+                if spans is not None:
+                    for span in spans:
+                        if span.service:
+                            # report extra service name as it may have been set after the span creation by the customer
+                            config._add_extra_service(span.service)
                 self.writer.write(spans)
                 return
 

releasenotes/notes/report_extra_service_names_from_spans-b98b87fbefe97337.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - |
+    Tracer: This fix resolves an issue where programmatically set span services names would not get reported to Remote Configuration.

tests/internal/service_name/test_extra_services_names.py

@@ -85,3 +85,28 @@ def test_config_extra_service_names_rc_disabled(run_python_code_in_subprocess):
     env["DD_REMOTE_CONFIGURATION_ENABLED"] = "false"
     stdout, stderr, status, _ = run_python_code_in_subprocess(code, env=env)
     assert status == 0, (stdout, stderr, status)
+
+
+def test_config_extra_service_names_customer_changes(run_python_code_in_subprocess):
+    code = """
+import ddtrace.auto
+import ddtrace
+import re
+import os
+import sys
+import time
+
+with ddtrace.tracer.trace("test") as parent:
+    parent.service = "parent_service"
+    with ddtrace.tracer.trace("child") as child:
+        child.service = "child_service"
+extra_services = ddtrace.config._get_extra_services()
+# collecting extra services in all spans, including the parent and child
+assert "parent_service" in extra_services
+assert "child_service" in extra_services
+    """
+
+    env = os.environ.copy()
+    env["DD_REMOTE_CONFIGURATION_ENABLED"] = "true"
+    stdout, stderr, status, _ = run_python_code_in_subprocess(code, env=env)
+    assert status == 0, (stdout, stderr, status)