synapse/contrib/example_log_config.yaml

# Example log_config file for synapse. To enable, point `log_config` to it in 
# `homeserver.yaml`, and restart synapse.
#
# This configuration will produce similar results to the defaults within 
# synapse, but can be edited to give more flexibility.

version: 1

formatters:
  fmt:
    format: '%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s- %(message)s'

filters:
  context:
    (): synapse.util.logcontext.LoggingContextFilter
    request: ""

handlers:
  # example output to console
  console:
    class: logging.StreamHandler
    formatter: fmt
    filters: [context]

  # example output to file - to enable, edit 'root' config below.
  file:
    class: logging.handlers.RotatingFileHandler
    formatter: fmt
    filename: /var/log/synapse/homeserver.log
    maxBytes: 100000000
    backupCount: 3
    filters: [context]
    encoding: utf8

root:
    level: INFO
    handlers: [console] # to use file handler instead, switch to [file]
    
loggers:
    synapse:
        level: INFO

    synapse.storage.SQL:
        # beware: increasing this to DEBUG will make synapse log sensitive
        # information such as access tokens.
        level: INFO

    # example of enabling debugging for a component:
    #
    # synapse.federation.transport.server:
    #    level: DEBUG