Log Default

LogDefault is the built-in log provider. It supports file logging, console logging, or both, with simple text or JSON output format.

This is the provider used when no log is explicitly configured in Config.

Parameters

Parameter	Values	Default	Description
level	DEBUG, INFO, WARNING, ERROR	INFO	Minimum log level
output	file, console, both	console	Where logs are written
path	Any file path	.output/flow.log	Log file location (used with file or both)
format	simple, json	simple	Message format

Basic example

Console output with simple format:

Python 3.8+

from dotflow import Config, DotFlow, action
from dotflow.providers import LogDefault


@action
def extract():
    return {"data": "fetched"}


@action
def transform(previous_context):
    return {"result": previous_context.storage}


def main():
    log = LogDefault(
        level="INFO",
        output="console",
        format="simple",
    )

    workflow = DotFlow(config=Config(log=log))
    workflow.task.add(step=extract)
    workflow.task.add(step=transform)
    workflow.start()

    return workflow


if __name__ == "__main__":
    main()

Output:

2026-04-07 14:31:07 - INFO [dotflow]: ID abc-123 - 01ARZ3NDEKTSV4RRFFQ69G5FAV - Not started
2026-04-07 14:31:07 - INFO [dotflow]: ID abc-123 - 01ARZ3NDEKTSV4RRFFQ69G5FAV - In progress
2026-04-07 14:31:07 - INFO [dotflow]: ID abc-123 - 01ARZ3NDEKTSV4RRFFQ69G5FAV - Completed

JSON format

JSON output to both console and file — useful for log aggregation tools (ELK, Loki, Datadog).

Python 3.8+

from dotflow import Config, DotFlow, action
from dotflow.providers import LogDefault


@action
def extract():
    return {"data": "fetched"}


@action
def transform(previous_context):
    return {"result": previous_context.storage}


def main():
    log = LogDefault(
        level="DEBUG",
        output="both",
        path=".output/pipeline.log",
        format="json",
    )

    workflow = DotFlow(config=Config(log=log))
    workflow.task.add(step=extract)
    workflow.task.add(step=transform)
    workflow.start()

    return workflow


if __name__ == "__main__":
    main()

Output:

{"timestamp": "2026-04-07T19:34:24.626Z", "level": "INFO", "workflow_id": "abc-123", "task_id": "01ARZ3NDEKTSV4RRFFQ69G5FAV", "status": "Completed", "duration": 0.0001}

Log levels

Level	Logged when
INFO	Task status changes (Not started, In progress, Completed)
WARNING	Task status changes to Retry
ERROR	Task status changes to Failed (includes traceback)
DEBUG	Available for custom use

References

• LogDefault
• Log OpenTelemetry