Loggers

@dagster.logger(config_schema=None, description=None)[source]

Define a logger.

The decorated function should accept an InitLoggerContext and return an instance of logging.Logger. This function will become the logger_fn of an underlying LoggerDefinition.

Parameters
  • config_schema (Optional[ConfigSchema]) – The schema for the config. Configuration data available in init_context.logger_config.

  • description (Optional[str]) – A human-readable description of the logger.

class dagster.LoggerDefinition(logger_fn, config_schema=None, description=None, _configured_config_mapping_fn=None)[source]

Core class for defining loggers.

Loggers are pipeline-scoped logging handlers, which will be automatically invoked whenever solids in a pipeline log messages.

Parameters
  • logger_fn (Callable[[InitLoggerContext], logging.Logger]) – User-provided function to instantiate the logger. This logger will be automatically invoked whenever the methods on context.log are called from within solid compute logic.

  • config_schema (Optional[ConfigSchema]) – The schema for the config. Configuration data available in init_context.logger_config.

  • description (Optional[str]) – A human-readable description of this logger.

  • _configured_config_mapping_fn – This argument is for internal use only. Users should not specify this field. To preconfigure a resource, use the configured() API.

class dagster.InitLoggerContext[source]

Logger-specific initialization context.

An instance of this class is made available as the first argument to the logger_fn decorated by @logger or set on a LoggerDefinition.

Users should not instantiate this class.

logger_config

The configuration data provided by the environment config. The schema for this data is defined by config_field on the LoggerDefinition

Type

Any

pipeline_def

The pipeline definition currently being executed.

Type

PipelineDefinition

logger_def

The logger definition for the logger being constructed.

Type

LoggerDefinition

run_id

The ID for this run of the pipeline.

Type

str