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Source code for google.appengine.api.app_logging

#!/usr/bin/env python
# Copyright 2007 Google Inc.
# 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
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# See the License for the specific language governing permissions and
# limitations under the License.

"""Logging utilities for use by applications.

Classes defined here:
  AppLogsHandler: StreamHandler subclass

import logging

from google.appengine import runtime
from google.appengine.api import logservice
from google.appengine.runtime import features


[docs]class AppLogsHandler(logging.Handler): """Logging handler that will direct output to a persistent store of application logs. This handler will output log statements to logservice.write(). This handler is automatically initialized and attached to the Python common logging library. """
[docs] def emit(self, record): """Emit a record. This implementation is based on the implementation of StreamHandler.emit(). Args: record: A Python logging.LogRecord object. """ try: if features.IsEnabled("LogServiceWriteRecord"): logservice.write_record(self._AppLogsLevel(record.levelno), record.created, self.format(record), self._AppLogsLocation(record)) else: message = self._AppLogsMessage(record) if isinstance(message, unicode): message = message.encode("UTF-8") logservice.write(message) except (KeyboardInterrupt, SystemExit, runtime.DeadlineExceededError): raise except: self.handleError(record)
def _AppLogsMessage(self, record): """Converts the log record into a log line.""" message = self.format(record).replace("\r\n", NEWLINE_REPLACEMENT) message = message.replace("\r", NEWLINE_REPLACEMENT) message = message.replace("\n", NEWLINE_REPLACEMENT) return "LOG %d %d %s\n" % (self._AppLogsLevel(record.levelno), long(record.created * 1000 * 1000), message) def _AppLogsLevel(self, level): """Converts the logging level used in Python to the API logging level.""" if level >= logging.CRITICAL: return 4 elif level >= logging.ERROR: return 3 elif level >= logging.WARNING: return 2 elif level >= logging.INFO: return 1 else: return 0 def _AppLogsLocation(self, record): """Find the source location responsible for calling the logging API.""" return (getattr(record, "pathname", None), getattr(record, "lineno", None), getattr(record, "funcName", None))