fix(grpc): disable aio support [backport 2.9] (#9201)

Backport 4c6247b from #9182 to 2.9.

The goal of this PR is to unblock the 2.9.0 release.

This PR hides grpc.aio support behind an internal flag. This integration
is broken and will be fixed in a future release.

## Checklist

- [x] Change(s) are motivated and described in the PR description
- [x] Testing strategy is described if automated tests are not included
in the PR
- [x] Risks are described (performance impact, potential for breakage,
maintainability)
- [x] Change is maintainable (easy to change, telemetry, documentation)
- [x] [Library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
are followed or label `changelog/no-changelog` is set
- [x] Documentation is included (in-code, generated user docs, [public
corp docs](https://github.com/DataDog/documentation/))
- [x] Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))
- [x] If this PR changes the public interface, I've notified
`@DataDog/apm-tees`.

## Reviewer Checklist

- [x] Title is accurate
- [x] All changes are related to the pull request's stated goal
- [x] Description motivates each change
- [x] Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- [x] Testing strategy adequately addresses listed risks
- [x] Change is maintainable (easy to change, telemetry, documentation)
- [x] Release note makes sense to a user of the library
- [x] Author has acknowledged and discussed the performance implications
of this PR as reported in the benchmarks PR comment
- [x] Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

Co-authored-by: Munir Abdinur <[email protected]>

Author: github-actions[bot]

ddtrace/contrib/grpc/patch.py

@@ -1,12 +1,16 @@
+import os
+
 import grpc
 
 from ddtrace import Pin
 from ddtrace import config
 from ddtrace.internal.schema import schematize_service_name
 from ddtrace.vendor.wrapt import wrap_function_wrapper as _w
 
+from ...internal.logger import get_logger
 from ...internal.utils import get_argument_value
 from ...internal.utils import set_argument_value
+from ...internal.utils.formats import asbool
 from ..trace_utils import unwrap as _u
 from . import constants
 from . import utils
@@ -15,6 +19,9 @@
 from .server_interceptor import create_server_interceptor
 
 
+log = get_logger(__name__)
+
+
 def get_version():
     # type: () -> str
     return getattr(grpc, "__version__", "")
@@ -63,6 +70,8 @@ def get_version():
     dict(
         _default_service=schematize_service_name(constants.GRPC_SERVICE_CLIENT),
         distributed_tracing_enabled=True,
+        # TODO: Remove this configuration when grpc.aio support is fixed
+        _grpc_aio_enabled=asbool(os.getenv("_DD_TRACE_GRPC_AIO_ENABLED", False)),
     ),
 )
 
@@ -88,15 +97,16 @@ def get_version():
 def patch():
     _patch_client()
     _patch_server()
-    if HAS_GRPC_AIO:
+    if HAS_GRPC_AIO and config.grpc._grpc_aio_enabled:
+        log.debug("The ddtrace grpc aio patch is enabled. This is an experimental feature and may not be stable.")
         _patch_aio_client()
         _patch_aio_server()
 
 
 def unpatch():
     _unpatch_client()
     _unpatch_server()
-    if HAS_GRPC_AIO:
+    if HAS_GRPC_AIO and config.grpc._grpc_aio_enabled:
         _unpatch_aio_client()
         _unpatch_aio_server()
 

releasenotes/notes/disable-76545e225ff1b3f4.yaml

@@ -0,0 +1,4 @@
+---
+issues:
+  - |
+    grpc: Tracing for the ``grpc.aio`` clients and servers is experimental and may not be stable. This integration is now disabled by default.

riotfile.py

@@ -1735,6 +1735,8 @@ def select_pys(min_version=MIN_PYTHON_VERSION, max_version=MAX_PYTHON_VERSION):
                 "pytest-asyncio": "==0.21.1",
                 "pytest-randomly": latest,
             },
+            # grpc.aio support is broken and disabled by default
+            env={"_DD_TRACE_GRPC_AIO_ENABLED": "true"},
             venvs=[
                 Venv(
                     pys=select_pys(min_version="3.7", max_version="3.9"),