Fix issue 2485 enable caching for get_logger calls

Cache one Logger object per Python logger name in LoggingHandler

Author: tm0nk

Diff for: opentelemetry-sdk/src/opentelemetry/sdk/_logs/_internal/__init__.py

@@ -20,6 +20,7 @@
 import threading
 import traceback
 import warnings
+from functools import lru_cache
 from os import environ
 from time import time_ns
 from typing import Any, Callable, Optional, Tuple, Union  # noqa
@@ -471,9 +472,6 @@ def __init__(
     ) -> None:
         super().__init__(level=level)
         self._logger_provider = logger_provider or get_logger_provider()
-        self._logger = get_logger(
-            __name__, logger_provider=self._logger_provider
-        )
 
     @staticmethod
     def _get_attributes(record: logging.LogRecord) -> Attributes:
@@ -558,6 +556,7 @@ def _translate(self, record: logging.LogRecord) -> LogRecord:
             "WARN" if record.levelname == "WARNING" else record.levelname
         )
 
+        logger = get_logger(record.name, logger_provider=self._logger_provider)
         return LogRecord(
             timestamp=timestamp,
             observed_timestamp=observered_timestamp,
@@ -567,7 +566,7 @@ def _translate(self, record: logging.LogRecord) -> LogRecord:
             severity_text=level_name,
             severity_number=severity_number,
             body=body,
-            resource=self._logger.resource,
+            resource=logger.resource,
             attributes=attributes,
         )
 
@@ -577,15 +576,15 @@ def emit(self, record: logging.LogRecord) -> None:
 
         The record is translated to OTel format, and then sent across the pipeline.
         """
-        if not isinstance(self._logger, NoOpLogger):
-            self._logger.emit(self._translate(record))
+        logger = get_logger(record.name, logger_provider=self._logger_provider)
+        if not isinstance(logger, NoOpLogger):
+            logger.emit(self._translate(record))
 
     def flush(self) -> None:
         """
         Flushes the logging output. Skip flushing if logger is NoOp.
         """
-        if not isinstance(self._logger, NoOpLogger):
-            self._logger_provider.force_flush()
+        self._logger_provider.force_flush()
 
 
 class Logger(APILogger):
@@ -647,6 +646,7 @@ def __init__(
     def resource(self):
         return self._resource
 
+    @lru_cache(maxsize=None)
     def get_logger(
         self,
         name: str,

Diff for: opentelemetry-sdk/tests/logs/test_export.py

@@ -71,6 +71,9 @@ def test_simple_log_record_processor_default_level(self):
         self.assertEqual(
             warning_log_record.severity_number, SeverityNumber.WARN
         )
+        self.assertEqual(
+            finished_logs[0].instrumentation_scope.name, "default_level"
+        )
 
     def test_simple_log_record_processor_custom_level(self):
         exporter = InMemoryLogExporter()
@@ -104,6 +107,12 @@ def test_simple_log_record_processor_custom_level(self):
         self.assertEqual(
             fatal_log_record.severity_number, SeverityNumber.FATAL
         )
+        self.assertEqual(
+            finished_logs[0].instrumentation_scope.name, "custom_level"
+        )
+        self.assertEqual(
+            finished_logs[1].instrumentation_scope.name, "custom_level"
+        )
 
     def test_simple_log_record_processor_trace_correlation(self):
         exporter = InMemoryLogExporter()
@@ -129,6 +138,9 @@ def test_simple_log_record_processor_trace_correlation(self):
         self.assertEqual(
             log_record.trace_flags, INVALID_SPAN_CONTEXT.trace_flags
         )
+        self.assertEqual(
+            finished_logs[0].instrumentation_scope.name, "trace_correlation"
+        )
         exporter.clear()
 
         tracer = trace.TracerProvider().get_tracer(__name__)
@@ -140,6 +152,10 @@ def test_simple_log_record_processor_trace_correlation(self):
             self.assertEqual(log_record.body, "Critical message within span")
             self.assertEqual(log_record.severity_text, "CRITICAL")
             self.assertEqual(log_record.severity_number, SeverityNumber.FATAL)
+            self.assertEqual(
+                finished_logs[0].instrumentation_scope.name,
+                "trace_correlation",
+            )
             span_context = span.get_span_context()
             self.assertEqual(log_record.trace_id, span_context.trace_id)
             self.assertEqual(log_record.span_id, span_context.span_id)
@@ -166,6 +182,9 @@ def test_simple_log_record_processor_shutdown(self):
         self.assertEqual(
             warning_log_record.severity_number, SeverityNumber.WARN
         )
+        self.assertEqual(
+            finished_logs[0].instrumentation_scope.name, "shutdown"
+        )
         exporter.clear()
         logger_provider.shutdown()
         with self.assertLogs(level=logging.WARNING):
@@ -206,6 +225,10 @@ def test_simple_log_record_processor_different_msg_types(self):
             for item in finished_logs
         ]
         self.assertEqual(expected, emitted)
+        for item in finished_logs:
+            self.assertEqual(
+                item.instrumentation_scope.name, "different_msg_types"
+            )
 
     def test_simple_log_record_processor_different_msg_types_with_formatter(
         self,
@@ -428,6 +451,8 @@ def test_shutdown(self):
             for item in finished_logs
         ]
         self.assertEqual(expected, emitted)
+        for item in finished_logs:
+            self.assertEqual(item.instrumentation_scope.name, "shutdown")
 
     def test_force_flush(self):
         exporter = InMemoryLogExporter()
@@ -447,6 +472,9 @@ def test_force_flush(self):
         log_record = finished_logs[0].log_record
         self.assertEqual(log_record.body, "Earth is burning")
         self.assertEqual(log_record.severity_number, SeverityNumber.FATAL)
+        self.assertEqual(
+            finished_logs[0].instrumentation_scope.name, "force_flush"
+        )
 
     def test_log_record_processor_too_many_logs(self):
         exporter = InMemoryLogExporter()
@@ -465,6 +493,8 @@ def test_log_record_processor_too_many_logs(self):
         self.assertTrue(log_record_processor.force_flush())
         finised_logs = exporter.get_finished_logs()
         self.assertEqual(len(finised_logs), 1000)
+        for item in finised_logs:
+            self.assertEqual(item.instrumentation_scope.name, "many_logs")
 
     def test_with_multiple_threads(self):
         exporter = InMemoryLogExporter()
@@ -492,6 +522,8 @@ def bulk_log_and_flush(num_logs):
 
         finished_logs = exporter.get_finished_logs()
         self.assertEqual(len(finished_logs), 2415)
+        for item in finished_logs:
+            self.assertEqual(item.instrumentation_scope.name, "threads")
 
     @unittest.skipUnless(
         hasattr(os, "fork"),