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)[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_or_config_fn: Any, config_schema: Optional[Dict[str, Any]] = None, description: Optional[str] = None)¶

Wraps this object in an object of the same type that provides configuration to the inner object.

Parameters

• config_or_config_fn (Union[Any, Callable[[Any], Any]]) – Either (1) Run configuration that fully satisfies this object’s config schema or (2) A function that accepts run configuration and returns run configuration that fully satisfies this object’s config schema. In the latter case, config_schema must be specified. When passing a function, it’s easiest to use configured().

• config_schema (ConfigSchema) – If config_or_config_fn is a function, the config schema that its input must satisfy.

• description (Optional[str]) – Description of the new definition. If not specified, inherits the description of the definition being configured.

Returns (ConfigurableDefinition): A configured version of this object.

class dagster.InitLoggerContext(logger_config: Any, logger_def: dagster.core.definitions.logger.LoggerDefinition, pipeline_def: Optional[dagster.core.definitions.pipeline.PipelineDefinition] = None, run_id: Optional[str] = None)[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_schema 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