asyncio: fix duplicate instrumentation

CHANGELOG.md

@@ -27,6 +27,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   ([#3113](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/3113))
 - `opentelemetry-instrumentation-grpc` Fix error when using gprc versions <= 1.50.0 with unix sockets.
   ([[#3393](https://github.com/open-telemetry/opentelemetry-python-contrib/issues/3393)])
+- `opentelemetry-instrumentation-asyncio` Fix duplicate instrumentation.
+  ([[#3383](https://github.com/open-telemetry/opentelemetry-python-contrib/issues/3383)])
 
 ## Version 1.31.0/0.52b0 (2025-03-12)
 

instrumentation/opentelemetry-instrumentation-asyncio/src/opentelemetry/instrumentation/asyncio/__init__.py

@@ -93,6 +93,10 @@ def func():
 
 from wrapt import wrap_function_wrapper as _wrap
 
+from opentelemetry.instrumentation.asyncio.instrumentation_state import (
+    _is_instrumented,
+    _mark_instrumented,
+)
 from opentelemetry.instrumentation.asyncio.package import _instruments
 from opentelemetry.instrumentation.asyncio.utils import (
     get_coros_to_trace,
@@ -237,7 +241,14 @@ def wrap_taskgroup_create_task(method, instance, args, kwargs) -> None:
         )
 
     def trace_to_thread(self, func: callable):
-        """Trace a function."""
+        """
+        Trace a function, but if already instrumented, skip double-wrapping.
+        """
+        if _is_instrumented(func):
+            return func
+
+        _mark_instrumented(func)
+
         start = default_timer()
         func_name = getattr(func, "__name__", None)
         if func_name is None and isinstance(func, functools.partial):
@@ -270,6 +281,15 @@ def trace_item(self, coro_or_future):
         return coro_or_future
 
     async def trace_coroutine(self, coro):
+        """
+        Wrap a coroutine so that we measure its duration, metrics, etc.
+        If already instrumented, simply 'await coro' to preserve call behavior.
+        """
+        if _is_instrumented(coro):
+            return await coro
+
+        _mark_instrumented(coro)
+
         if not hasattr(coro, "__name__"):
             return await coro
         start = default_timer()
@@ -303,6 +323,14 @@ async def trace_coroutine(self, coro):
             self.record_process(start, attr, span, exception)
 
     def trace_future(self, future):
+        """
+        Wrap a Future's done callback. If already instrumented, skip re-wrapping.
+        """
+        if _is_instrumented(future):
+            return future
+
+        _mark_instrumented(future)
+
         start = default_timer()
         span = (
             self._tracer.start_span(f"{ASYNCIO_PREFIX} future")

instrumentation/opentelemetry-instrumentation-asyncio/src/opentelemetry/instrumentation/asyncio/instrumentation_state.py

@@ -0,0 +1,74 @@
+"""
+Instrumentation State Tracker
+
+This module provides helper functions to safely track whether a coroutine,
+Future, or function has already been instrumented by the OpenTelemetry
+asyncio instrumentation layer.
+
+Because some Python objects (like coroutines or functions) may not support
+adding custom attributes or may not be weak-referenceable, we use a
+weak-reference-based dictionary to track instrumented objects safely and
+efficiently without causing memory leaks.
+
+If an object cannot be weak-referenced, we skip tracking it to avoid
+runtime errors.
+
+Usage:
+    if not _is_instrumented(obj):
+        _mark_instrumented(obj)
+        # instrument the object...
+"""
+
+import weakref
+
+# A global dictionary to track whether an object has been instrumented.
+# Keys are weak references to avoid preventing garbage collection.
+_instrumented_tasks = {}
+
+
+def _get_weak_key(obj):
+    """
+    Attempt to create a weak reference key for the given object.
+
+    Some object types (e.g., built-in functions or async_generator_asend)
+    do not support weak references. In those cases, return None.
+
+    Args:
+        obj: The object to generate a weak reference for.
+
+    Returns:
+        A weakref.ref to the object if supported, otherwise None.
+    """
+    try:
+        return weakref.ref(obj)
+    except TypeError:
+        return None
+
+
+def _is_instrumented(obj) -> bool:
+    """
+    Check if the object has already been instrumented.
+
+    Args:
+        obj: The coroutine, function, or Future to check.
+
+    Returns:
+        True if the object is already marked as instrumented, False otherwise.
+    """
+    key = _get_weak_key(obj)
+    return key in _instrumented_tasks if key else False
+
+
+def _mark_instrumented(obj):
+    """
+    Mark the object as instrumented to avoid double-instrumentation.
+
+    Only objects that support weak references are tracked. Unsupported
+    objects are silently skipped.
+
+    Args:
+        obj: The coroutine, function, or Future to mark.
+    """
+    key = _get_weak_key(obj)
+    if key:
+        _instrumented_tasks[key] = True

instrumentation/opentelemetry-instrumentation-asyncio/tests/test_asyncio_duplicate_instrument.py

@@ -0,0 +1,115 @@
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""
+A general test verifying that when the same Future objects (or coroutines) are
+repeatedly instrumented (for example, via `trace_future`), callback references
+do not leak. In this example, we mimic a typical scenario where a small set of
+Futures might be reused throughout an application's lifecycle.
+"""
+
+import asyncio
+
+from opentelemetry.instrumentation.asyncio import AsyncioInstrumentor
+from opentelemetry.test.test_base import TestBase
+
+
+class MockSubscription:
+    """
+    Example class holding an unsubscribe_future, similar to something like
+    aiokafka's subscription.
+    """
+
+    def __init__(self):
+        self.unsubscribe_future = asyncio.Future()
+
+
+class MockGroupCoordinator:
+    """
+    Example class modeling repeated instrumentation of the same Future objects.
+    """
+
+    def __init__(self):
+        self._closing = asyncio.Future()
+        self.subscription = MockSubscription()
+        self._rejoin_needed_fut = asyncio.Future()
+
+    async def run_routine(self, instrumentor):
+        """
+        Each time this routine is called, the same 3 Futures are 'traced' again.
+        In a real-life scenario, there's often a loop reusing these objects.
+        """
+        instrumentor.trace_future(self._closing)
+        instrumentor.trace_future(self.subscription.unsubscribe_future)
+        instrumentor.trace_future(self._rejoin_needed_fut)
+
+
+class TestAsyncioDuplicateInstrument(TestBase):
+    """
+    Tests whether repeated instrumentation of the same Futures leads to
+    exponential callback growth (potential memory leak).
+    """
+
+    def setUp(self):
+        super().setUp()
+        self.loop = asyncio.new_event_loop()
+        asyncio.set_event_loop(self.loop)
+
+        self.instrumentor = AsyncioInstrumentor()
+        self.instrumentor.instrument()
+
+    def tearDown(self):
+        self.instrumentor.uninstrument()
+        self.loop.close()
+        asyncio.set_event_loop(None)
+        super().tearDown()
+
+    def test_duplicate_instrumentation_of_futures(self):
+        """
+        If instrumentor.trace_future is called multiple times on the same Future,
+        we should NOT see an unbounded accumulation of callbacks.
+        """
+        coordinator = MockGroupCoordinator()
+
+        # Simulate calling the routine multiple times
+        num_iterations = 10
+        for _ in range(num_iterations):
+            self.loop.run_until_complete(
+                coordinator.run_routine(self.instrumentor)
+            )
+
+        # Check for callback accumulation
+        closing_cb_count = len(coordinator._closing._callbacks)
+        unsub_cb_count = len(
+            coordinator.subscription.unsubscribe_future._callbacks
+        )
+        rejoin_cb_count = len(coordinator._rejoin_needed_fut._callbacks)
+
+        # If instrumentation is properly deduplicated, each Future might have ~1-2 callbacks.
+        max_expected_callbacks = 2
+        self.assertLessEqual(
+            closing_cb_count,
+            max_expected_callbacks,
+            f"_closing Future has {closing_cb_count} callbacks. Potential leak!",
+        )
+        self.assertLessEqual(
+            unsub_cb_count,
+            max_expected_callbacks,
+            f"unsubscribe_future has {unsub_cb_count} callbacks. Potential leak!",
+        )
+        self.assertLessEqual(
+            rejoin_cb_count,
+            max_expected_callbacks,
+            f"_rejoin_needed_fut has {rejoin_cb_count} callbacks. Potential leak!",
+        )