Logging

BentoML API server logs all the prediction requests and their responses under the $BENTOML_HOME/logs directory by default in a local development environment. When deploying with Docker, the logs can be found under the /home/bentoml/logs directory.

BentoML uses standard Python logging module and provides logging customization through logging section in bentoml.cfg under the BentoML home directory. Refer to the configuration guide on how override configuration properties. See default_bentoml.cfg for a list of override-able properties.

For advanced logging customization, user can provide full logging configurations in logging.yml, placed under the BentoML home directory. For example, logging.yml configuration file can be injected into the Docker container through the following command:

$ docker run -v /local/path/to/logging.yml:/home/bentoml/logging.yml

Please see below configuration examples of different logging scenarios in YAML format.

Enable INFO+ console logging but only WARN+ file logging.

version: 1
disable_existing_loggers: False
formatters:
    console:
        format: '[%(asctime)s] %(levelname)s - %(message)s'
    dev:
        format: '[%(asctime)s] {{%(filename)s:%(lineno)d}} %(levelname)s - %(message)s'
handlers:
    console:
        level: INFO
        formatter: console
        class: logging.StreamHandler
        stream: ext://sys.stdout
    local:
        level: WARN
        formatter: dev
        class: logging.handlers.RotatingFileHandler
        filename: '/var/log/bentoml/active.log'
        maxBytes: 104857600
        backupCount: 2
loggers:
    bentoml:
        handlers: [console, local]
        level: INFO
        propagate: False
    bentoml.prediction:
        handlers: [console]
        level: INFO
        propagate: False
    bentoml.feedback:
        handlers: [console]
        level: INFO
        propagate: False

Disable all logging except prediction and feedback file logging.

version: 1
disable_existing_loggers: False
formatters:
    prediction:
        (): pythonjsonlogger.jsonlogger.JsonFormatter
    feedback:
        (): pythonjsonlogger.jsonlogger.JsonFormatter
handlers:
    prediction:
        class: logging.handlers.RotatingFileHandler
        formatter: prediction
        level: INFO
        filename: '/var/log/bentoml/prediction.log'
        maxBytes: 104857600
        backupCount: 10
    feedback:
        class: logging.handlers.RotatingFileHandler
        formatter: feedback
        level: INFO
        filename: '/var/log/bentoml/feedback.log'
        maxBytes: 104857600
        backupCount: 10
loggers:
    bentoml:
        handlers: []
        level: INFO
        propagate: False
    bentoml.prediction:
        handlers: [prediction]
        level: INFO
        propagate: False
    bentoml.feedback:
        handlers: [feedback]
        level: INFO
        propagate: False

Default logging configuration.

version: 1
disable_existing_loggers: False
formatters:
    console:
        format: '[%(asctime)s] %(levelname)s - %(message)s'
    dev:
        format: '[%(asctime)s] {{%(filename)s:%(lineno)d}} %(levelname)s - %(message)s'
    prediction:
        (): pythonjsonlogger.jsonlogger.JsonFormatter
    feedback:
        (): pythonjsonlogger.jsonlogger.JsonFormatter
handlers:
    console:
        level: INFO
        formatter: console
        class: logging.StreamHandler
        stream: ext://sys.stdout
    local:
        level: INFO
        formatter: dev
        class: logging.handlers.RotatingFileHandler
        filename: '/var/log/bentoml/active.log'
        maxBytes: 104857600
        backupCount: 2
    prediction:
        class: logging.handlers.RotatingFileHandler
        formatter: prediction
        level: INFO
        filename: '/var/log/bentoml/prediction.log'
        maxBytes: 104857600
        backupCount: 10
    feedback:
        class: logging.handlers.RotatingFileHandler
        formatter: feedback
        level: INFO
        filename: '/var/log/bentoml/feedback.log'
        maxBytes: 104857600
        backupCount: 10
loggers:
    bentoml:
        handlers: [console, local]
        level: INFO
        propagate: False
    bentoml.prediction:
        handlers: [console, prediction]
        level: INFO
        propagate: False
    bentoml.feedback:
        handlers: [console, feedback]
        level: INFO
        propagate: False