Add TraceLoggingFilter

[gukoff]

Filters are another, flexible way to add contextual information to the logs.

A filter can be attached to both a Logger and a Handler, allowing for more granular control on how to add contextual information to a log record.

E.g., a filter can be attached only to a opencensus export handler. And this will affect all log records emitted to handler, even if you use plain logging.info(...) instead of logging.getLogger(__name__).info(...).

Example:

def configure_logging():
    handler = AzureLogHandler(
        connection_string=app_insights_conn_str,
        sampler=AlwaysOnSampler(),
        credential=credential,
    )
    root = logging.getLogger()
    root.addHandler(handler)
    handler.addFilter(TraceLoggingFilter())

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[gukoff]

Friendly ping? (: