Added excessive logging threshold test (#37274)

* Added excessive logging threshold tests
* Excessive logs sample:

```
Warning: Excessive error output detected (7 lines):
WARNING: All log messages before absl::InitializeLog() is called are written to STDERR

I0000 00:00:1724852923.140229      45 chttp2_transport.cc:1182] ipv6:%5B::1%5D:45545: Got goaway [2] err=UNAVAILABLE:GOAWAY received; Error code: 2; Debug Text: Cancelling all calls {file:"src/core/ext/transport/chttp2/transport/chttp2_transport.cc", file_line:1171, created_time:"2024-08-28T13:48:43.140192497+00:00", http2_error:2, grpc_status:14}
```

Closes #37274

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/37274 from sourabhsinghs:unittest/logging-threshold 09a87693d0
PiperOrigin-RevId: 678742613

bazel/BUILD

@@ -20,7 +20,17 @@ licenses(["notice"])
 
 package(default_visibility = ["//:__subpackages__"])
 
+filegroup(
+    name = "_single_module_tester",
+    srcs = ["_single_module_tester.py"],
+)
+
 filegroup(
     name = "_gevent_test_main",
     srcs = ["_gevent_test_main.py"],
 )
+
+filegroup(
+    name = "_logging_threshold_test_main",
+    srcs = ["_logging_threshold_test_main.py"],
+)

bazel/_logging_threshold_test_main.py

@@ -0,0 +1,93 @@
+# Copyright 2024 gRPC 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.
+
+import os
+import re
+import subprocess
+import sys
+import tempfile
+
+_OK_TEST_REGEX = r"^-+.*Ran ([\d]+) tests* in ([\d.]+)s.*OK(?: \(skipped=(\d+)\))?\n$"
+
+# Tests with known exception logs.
+# TODO(sourabhsinghs): Investigate and enable _rpc_part_1_test and _rpc_part_2_test tests.
+_SKIP_TESTS = [
+    "_rpc_part_1_test",
+    "_server_shutdown_test",
+    "_xds_credentials_test",
+    "_server_test",
+    "_invalid_metadata_test",
+    "_reconnect_test",
+    "_channel_close_test",
+    "_rpc_part_2_test",
+    "_invocation_defects_test",
+    "_dynamic_stubs_test",
+    "_channel_connectivity_test",
+]
+
+if __name__ == "__main__":
+    if len(sys.argv) != 3:
+        print(f"USAGE: {sys.argv[0]} TARGET_MODULE", file=sys.stderr)
+        sys.exit(1)
+
+    test_script = sys.argv[1]
+    target_module = sys.argv[2]
+
+    if target_module in _SKIP_TESTS:
+        print(f"Skipping {target_module}")
+        sys.exit(0)
+
+    command = [
+        sys.executable,
+        os.path.realpath(test_script),
+        target_module,
+        os.path.dirname(os.path.relpath(__file__)),
+    ]
+
+    with tempfile.TemporaryFile(mode="w+") as stdout_file:
+        with tempfile.TemporaryFile(mode="w+") as stderr_file:
+            result = subprocess.run(
+                command,
+                stdout=stdout_file,
+                stderr=stderr_file,
+                text=True,
+                check=True,
+            )
+
+            stdout_file.seek(0)
+            stderr_file.seek(0)
+
+            stdout_count = len(stdout_file.readlines())
+            stderr_count = len(stderr_file.readlines())
+
+            if result.returncode != 0:
+                sys.exit("Test failure")
+
+            stderr_file.seek(0)
+            if not re.fullmatch(_OK_TEST_REGEX, stderr_file.read(), re.DOTALL):
+                print(
+                    f"Warning: Excessive error output detected ({stderr_count} lines):"
+                )
+                stderr_file.seek(0)
+                for line in stderr_file:
+                    print(line)
+
+            if stdout_count > 0:
+                print(
+                    f"Warning: Unexpected output detected ({stdout_count} lines):"
+                )
+                stdout_file.seek(0)
+                for line in stdout_file:
+                    print(line)
+

bazel/_single_module_tester.py

@@ -0,0 +1,54 @@
+# Copyright 2024 gRPC 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.
+
+from typing import Sequence, Optional
+
+import unittest
+import sys
+import pkgutil
+
+
+class SingleLoader(object):
+    def __init__(self, pattern: str, unittest_path: str):
+        loader = unittest.TestLoader()
+        self.suite = unittest.TestSuite()
+        tests = []
+
+        for importer, module_name, is_package in pkgutil.walk_packages([unittest_path]):
+            if pattern in module_name:
+                module = importer.find_module(module_name).load_module(module_name)
+                tests.append(loader.loadTestsFromModule(module))
+        if len(tests) != 1:            
+            raise AssertionError("Expected only 1 test module. Found {}".format(tests))
+        self.suite.addTest(tests[0])
+
+    def loadTestsFromNames(self, names: Sequence[str], module: Optional[str] = None) -> unittest.TestSuite:
+        return self.suite
+
+if __name__ == "__main__":
+
+    if len(sys.argv) != 3:
+        print(f"USAGE: {sys.argv[0]} TARGET_MODULE", file=sys.stderr)
+        sys.exit(1)
+
+
+    target_module = sys.argv[1]
+    unittest_path = sys.argv[2]
+
+    loader = SingleLoader(target_module, unittest_path)
+    runner = unittest.TextTestRunner(verbosity=0)
+    result = runner.run(loader.suite)
+    
+    if not result.wasSuccessful():
+        sys.exit("Test failure.")

bazel/internal_python_rules.bzl

@@ -14,6 +14,7 @@
 """Python-related rules intended only for use internal to the repo."""
 
 load("//bazel:gevent_test.bzl", "py_grpc_gevent_test")
+load("//bazel:logging_threshold_test.bzl", "py_grpc_logging_threshold_test")
 
 def internal_py_grpc_test(name, **kwargs):
     """Runs a test under all supported environments.
@@ -28,6 +29,7 @@ def internal_py_grpc_test(name, **kwargs):
         **kwargs
     )
     py_grpc_gevent_test(name, **kwargs)
+    py_grpc_logging_threshold_test(name, **kwargs)
 
     suite_kwargs = {}
     if "visibility" in kwargs:
@@ -38,6 +40,7 @@ def internal_py_grpc_test(name, **kwargs):
         tests = [
             name + ".native",
             name + ".gevent",
+            name + ".logging_threshold",
         ],
         **suite_kwargs
     )

bazel/logging_threshold_test.bzl

@@ -0,0 +1,73 @@
+# Copyright 2024 The gRPC 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.
+"""
+Houses py_grpc_logging_threshold_test.
+"""
+
+_COPIED_MAIN_SUFFIX = ".logging_threshold.main"
+
+def py_grpc_logging_threshold_test(
+        name,
+        srcs,
+        main = None,
+        deps = None,
+        data = None,
+        **kwargs):
+    """Runs a Python unit test and checks amount of logging against a threshold.
+
+    Args:
+      name: The name of the test.
+      srcs: The source files.
+      main: The main file of the test.
+      deps: The dependencies of the test.
+      data: The data dependencies of the test.
+      **kwargs: Any other test arguments.
+    """
+    if main == None:
+        if len(srcs) != 1:
+            fail("When main is not provided, srcs must be of size 1.")
+        main = srcs[0]
+    deps = [] if deps == None else deps
+    data = [] if data == None else data
+
+    lib_name = name + ".logging_threshold.lib"
+    native.py_library(
+        name = lib_name,
+        srcs = srcs,
+    )
+    augmented_deps = deps + [
+        ":{}".format(lib_name),
+    ]
+
+    # The main file needs to be in the same package as the test file.
+    copied_main_name = name + _COPIED_MAIN_SUFFIX
+    copied_main_filename = copied_main_name + ".py"
+    native.genrule(
+        name = copied_main_name,
+        srcs = ["//bazel:_logging_threshold_test_main.py"],
+        outs = [copied_main_filename],
+        cmd = "cp $< $@",
+    )
+
+    native.py_test(
+        name = name + ".logging_threshold",
+        args = ["$(location //bazel:_single_module_tester)", name],
+        data = data + ["//bazel:_single_module_tester"],
+        deps = augmented_deps,
+        srcs = [copied_main_filename],
+        main = copied_main_filename,
+        python_version = "PY3",
+        flaky = False,
+        **kwargs
+    )

src/python/grpcio_tests/tests/unit/_signal_handling_test.py

@@ -208,8 +208,12 @@ class SignalHandlingTest(unittest.TestCase):
                 self._handler.await_connected_client()
                 client.send_signal(signal.SIGINT)
                 client.wait()
-                print(_read_stream(client_stderr))
-                self.assertEqual(0, client.returncode)
+                client_stderr_output = _read_stream(client_stderr)
+                try:
+                    self.assertEqual(0, client.returncode)
+                except AssertionError:
+                    print(client_stderr_output, file=sys.stderr)
+                    raise
 
 
 if __name__ == "__main__":