#!/usr/bin/env python3
"""
Minimal reproduction case for Sentry isolation_scope + async generator bug.
Bug: Using sentry_sdk.isolation_scope() as a context manager around an async
generator that yields causes "Token was created in a different Context" error
when the generator exits early (via break, exception, or garbage collection).
"""
import asyncio
import sentry_sdk
from sentry_sdk.integrations.asyncio import AsyncioIntegration
async def inner_generator():
"""Simple async generator that yields values"""
for i in range(3):
print(f" Inner generator yielding: {i}")
yield i
async def problematic_async_generator():
"""
This pattern causes the context error.
The isolation_scope wraps yield statements in an async generator.
"""
with sentry_sdk.isolation_scope() as scope:
scope.set_user({"id": "test-user-123"})
scope.set_tag("example", "value")
async for value in inner_generator():
# THIS YIELD INSIDE ISOLATION_SCOPE IS THE PROBLEM
yield value
async def main():
print("Reproducing Sentry isolation_scope + async generator bug\n")
print("=" * 60)
# Initialize Sentry
sentry_sdk.init(
dsn=None, # No DSN needed to reproduce
integrations=[AsyncioIntegration()],
debug=True,
)
print("Test 1: Normal completion (works fine)")
print("-" * 40)
async for val in problematic_async_generator():
print(f"Received: {val}")
print("✅ No error when generator completes normally\n")
print("Test 2: Early exit with break (causes error)")
print("-" * 40)
async for val in problematic_async_generator():
print(f"Received: {val}")
if val == 1:
print("Breaking early...")
break # This causes the context error
# Give time for error to appear in output
await asyncio.sleep(0.1)
print("\n❌ Error appears above: 'Token was created in a different Context'")
print("\n" + "=" * 60)
print("The error happens because:")
print("1. isolation_scope() saves the current context when entering")
print("2. The async generator suspends/resumes across context boundaries")
print("3. When exiting early, cleanup happens in a different context")
print("4. Python's contextvars raises ValueError")
if __name__ == "__main__":
asyncio.run(main())Test 2: Early exit with break (causes error)
----------------------------------------
Inner generator yielding: 0
Received: 0
Inner generator yielding: 1
Received: 1
Breaking early...
Task exception was never retrieved
future: <Task finished name='coroutine without __name__ (Sentry-wrapped)' coro=<patch_asyncio.<locals>._sentry_task_factory.<locals>._task_with_sentry_span_creation() done, defined at /Users/ntindle/Library/Caches/pypoetry/virtualenvs/autogpt-platform-backend-90-hPFvq-py3.12/lib/python3.12/site-packages/sentry_sdk/integrations/asyncio.py:42> exception=ValueError("<Token var=<ContextVar name='current_scope' default=None at 0x1033a7790> at 0x109af7300> was created in a different Context")>
Traceback (most recent call last):
File "/Users/ntindle/Library/Caches/pypoetry/virtualenvs/autogpt-platform-backend-90-hPFvq-py3.12/lib/python3.12/site-packages/sentry_sdk/scope.py", line 1755, in isolation_scope
yield new_isolation_scope
File "/Users/ntindle/code/agpt/AutoGPT/main/autogpt_platform/backend/./sentry_bug_repro.py", line 33, in problematic_async_generator
yield value
GeneratorExit
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/Users/ntindle/Library/Caches/pypoetry/virtualenvs/autogpt-platform-backend-90-hPFvq-py3.12/lib/python3.12/site-packages/sentry_sdk/integrations/asyncio.py", line 55, in _task_with_sentry_span_creation
reraise(*_capture_exception())
File "/Users/ntindle/Library/Caches/pypoetry/virtualenvs/autogpt-platform-backend-90-hPFvq-py3.12/lib/python3.12/site-packages/sentry_sdk/utils.py", line 1751, in reraise
raise value
File "/Users/ntindle/Library/Caches/pypoetry/virtualenvs/autogpt-platform-backend-90-hPFvq-py3.12/lib/python3.12/site-packages/sentry_sdk/integrations/asyncio.py", line 53, in _task_with_sentry_span_creation
result = await coro
^^^^^^^^^^
File "/Users/ntindle/code/agpt/AutoGPT/main/autogpt_platform/backend/./sentry_bug_repro.py", line 27, in problematic_async_generator
with sentry_sdk.isolation_scope() as scope:
File "/Library/Frameworks/Python.framework/Versions/3.12/lib/python3.12/contextlib.py", line 158, in __exit__
self.gen.throw(value)
File "/Users/ntindle/Library/Caches/pypoetry/virtualenvs/autogpt-platform-backend-90-hPFvq-py3.12/lib/python3.12/site-packages/sentry_sdk/scope.py", line 1760, in isolation_scope
_current_scope.reset(current_token)
ValueError: <Token var=<ContextVar name='current_scope' default=None at 0x1033a7790> at 0x109af7300> was created in a different Context
❌ Error appears above: 'Token was created in a different Context'
Save the scope user and tags, then manually catch the error in the generator using capture_exception, then set the tags using scope._tags = previous
How do you use Sentry?
Sentry Saas (sentry.io)
Version
2.33.2
Steps to Reproduce
Expected Result
Not to crash
Actual Result
Workaround
Save the scope user and tags, then manually catch the error in the generator using capture_exception, then set the tags using scope._tags = previous