feat: add automatic logging config to support debug logging

google/api_core/client_logging.py

@@ -0,0 +1,89 @@
+import logging
+import json
+import re
+import os
+
+_LOGGING_INITIALIZED = False
+_BASE_LOGGER_NAME = "google"
+# TODO(https://github.com/googleapis/python-api-core/issues/760): Update Request / Response messages.
+REQUEST_MESSAGE = "Sending request "
+RESPONSE_MESSAGE = "Receiving response "
+
+# TODO(https://github.com/googleapis/python-api-core/issues/761): Update this list to support additional logging fields
+_recognized_logging_fields = [
+    "httpRequest",
+    "rpcName",
+    "serviceName",
+]  # Additional fields to be Logged.
+
+
+def logger_configured(logger):
+    return (
+        logger.handlers != []
+        or logger.level != logging.NOTSET
+        or logger.propagate == False
+    )
+
+
+def initialize_logging():
+    global _LOGGING_INITIALIZED
+    if _LOGGING_INITIALIZED:
+        return
+    scopes = os.getenv("GOOGLE_SDK_PYTHON_LOGGING_SCOPE", "")
+    setup_logging(scopes)
+    _LOGGING_INITIALIZED = True
+
+
+def parse_logging_scopes(scopes):
+    if not scopes:
+        return []
+    # TODO(https://github.com/googleapis/python-api-core/issues/759): check if the namespace is a valid namespace.
+    # TODO(b/380481951): Support logging multiple scopes.
+    # TODO(b/380483756): Raise or log a warning for an invalid scope.
+    namespaces = [scopes]
+    return namespaces
+
+
+def configure_defaults(logger):
+    if not logger_configured(logger):
+        console_handler = logging.StreamHandler()
+        logger.setLevel("DEBUG")
+        logger.propagate = False
+        formatter = StructuredLogFormatter()
+        console_handler.setFormatter(formatter)
+        logger.addHandler(console_handler)
+
+
+def setup_logging(scopes=[]):
+
+    # only returns valid logger scopes (namespaces)
+    # this list has at most one element.
+    logger_names = parse_logging_scopes(scopes)
+
+    for namespace in logger_names:
+        # This will either create a module level logger or get the reference of the base logger instantiated above.
+        logger = logging.getLogger(namespace)
+
+        # Configure default settings.
+        configure_defaults(logger)
+
+    # disable log propagation at base logger level to the root logger only if a base logger is not already configured via code changes.
+    base_logger = logging.getLogger(_BASE_LOGGER_NAME)
+    if not logger_configured(base_logger):
+        base_logger.propagate = False
+
+
+class StructuredLogFormatter(logging.Formatter):
+    def format(self, record):
+        log_obj = {
+            "timestamp": self.formatTime(record),
+            "severity": record.levelname,
+            "name": record.name,
+            "message": record.getMessage(),
+        }
+
+        for field_name in _recognized_logging_fields:
+            value = getattr(record, field_name, None)
+            if value is not None:
+                log_obj[field_name] = value
+        return json.dumps(log_obj)

tests/unit/test_client_logging.py

@@ -0,0 +1,104 @@
+import logging
+import pytest
+import mock
+
+from google.api_core.client_logging import (
+    setup_logging,
+    initialize_logging,
+)
+
+
+def reset_logger(scope):
+    logger = logging.getLogger(scope)
+    logger.handlers = []
+    logger.setLevel(logging.NOTSET)
+    logger.propagate = True
+
+
+def test_setup_logging_w_no_scopes():
+    with mock.patch("google.api_core.client_logging._BASE_LOGGER_NAME", "foo"):
+        setup_logging()
+        base_logger = logging.getLogger("foo")
+        assert base_logger.handlers == []
+        assert base_logger.propagate == False
+        assert base_logger.level == logging.NOTSET
+
+    reset_logger("foo")
+
+
+def test_setup_logging_w_base_scope():
+    with mock.patch("google.api_core.client_logging._BASE_LOGGER_NAME", "foo"):
+        setup_logging("foo")
+    base_logger = logging.getLogger("foo")
+    assert isinstance(base_logger.handlers[0], logging.StreamHandler)
+    assert base_logger.propagate == False
+    assert base_logger.level == logging.DEBUG
+
+    reset_logger("foo")
+
+
+def test_setup_logging_w_module_scope():
+    with mock.patch("google.api_core.client_logging._BASE_LOGGER_NAME", "foo"):
+        setup_logging("foo.bar")
+
+    base_logger = logging.getLogger("foo")
+    assert base_logger.handlers == []
+    assert base_logger.propagate == False
+    assert base_logger.level == logging.NOTSET
+
+    module_logger = logging.getLogger("foo.bar")
+    assert isinstance(module_logger.handlers[0], logging.StreamHandler)
+    assert module_logger.propagate == False
+    assert module_logger.level == logging.DEBUG
+
+    reset_logger("foo")
+    reset_logger("foo.bar")
+
+
+def test_setup_logging_w_incorrect_scope():
+    with mock.patch("google.api_core.client_logging._BASE_LOGGER_NAME", "foo"):
+        setup_logging("abc")
+
+    base_logger = logging.getLogger("foo")
+    assert base_logger.handlers == []
+    assert base_logger.propagate == False
+    assert base_logger.level == logging.NOTSET
+
+    # TODO(https://github.com/googleapis/python-api-core/issues/759): update test once we add logic to ignore an incorrect scope.
+    logger = logging.getLogger("abc")
+    assert isinstance(logger.handlers[0], logging.StreamHandler)
+    assert logger.propagate == False
+    assert logger.level == logging.DEBUG
+
+    reset_logger("foo")
+    reset_logger("abc")
+
+
+def test_initialize_logging():
+
+    with mock.patch("os.getenv", return_value="foo.bar"):
+        with mock.patch("google.api_core.client_logging._BASE_LOGGER_NAME", "foo"):
+            initialize_logging()
+
+    base_logger = logging.getLogger("foo")
+    assert base_logger.handlers == []
+    assert base_logger.propagate == False
+    assert base_logger.level == logging.NOTSET
+
+    module_logger = logging.getLogger("foo.bar")
+    assert isinstance(module_logger.handlers[0], logging.StreamHandler)
+    assert module_logger.propagate == False
+    assert module_logger.level == logging.DEBUG
+
+    base_logger.propagate = True
+    module_logger.propagate = True
+
+    with mock.patch("os.getenv", return_value="foo.bar"):
+        with mock.patch("google.api_core.client_logging._BASE_LOGGER_NAME", "foo"):
+            initialize_logging()
+
+    assert base_logger.propagate == True
+    assert module_logger.propagate == True
+
+    reset_logger("foo")
+    reset_logger("foo.bar")