Duplicate log entries with Google Cloud Stackdriver logging of Python code on Kubernetes Engine

Question

I have a simple Python app running in a container on Google Kubernetes Engine. I am trying to connect the standard Python logging to Google Stackdriver logging using this gu

Answer 1

Problem is in the way how logging client initializes root logger

    logger = logging.getLogger()
    logger.setLevel(log_level)
    logger.addHandler(handler)
    logger.addHandler(logging.StreamHandler())

it adds default stream handler in addition to Stackdriver handler. My workaround for now is to initialize appropriate Stackdriver handler manually:

            # this basically manually sets logger compatible with GKE/fluentd
            # as LoggingClient automatically add another StreamHandler - so 
            # log records are duplicated
            from google.cloud.logging.handlers import ContainerEngineHandler
            formatter = logging.Formatter("%(message)s")
            handler = ContainerEngineHandler(stream=sys.stderr)
            handler.setFormatter(formatter)
            handler.setLevel(level)
            root = logging.getLogger()
            root.addHandler(handler)
            root.setLevel(level)