Prune autoinstrumentation sitecustomize module directory from PYTHONPATH immediately (#1066)

Author: aabmass

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.11.0-0.30b0...HEAD)
 
+- Prune autoinstrumentation sitecustomize module directory from PYTHONPATH immediately
+  ([#1066](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/1066))
+
 ## [1.11.0-0.30b0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.11.0-0.30b0) - 2022-04-18
 
 ### Fixed

opentelemetry-instrumentation/src/opentelemetry/instrumentation/auto_instrumentation/sitecustomize.py

@@ -110,19 +110,20 @@ def _load_configurators():
 
 
 def initialize():
+    # prevents auto-instrumentation of subprocesses if code execs another python process
+    environ["PYTHONPATH"] = sub(
+        rf"{dirname(abspath(__file__))}{pathsep}?",
+        "",
+        environ["PYTHONPATH"],
+    )
+
     try:
         distro = _load_distros()
         distro.configure()
         _load_configurators()
         _load_instrumentors(distro)
     except Exception:  # pylint: disable=broad-except
         logger.exception("Failed to auto initialize opentelemetry")
-    finally:
-        environ["PYTHONPATH"] = sub(
-            rf"{dirname(abspath(__file__))}{pathsep}?",
-            "",
-            environ["PYTHONPATH"],
-        )
 
 
 initialize()