donald 0.20.3

Donald is here

Donald – A fast and simple tasks manager for Asyncio.

Donald supports synchronous and asynchronous paradigms. The package is running coroutines and functions in multi loops. Donald could run periodic tasks and listen AMQP queues.

Contents

• Requirements

• Installation

• Quick Start

• Schedule tasks

• Run in production

• Bug tracker

• Contributing

• License

Requirements

• python 3.8+

Installation

Donald should be installed using pip:

pip install donald

With redis support:

pip install donald[redis]

Quick Start

Init the tasks manager:

# Init Donald
manager = Donald(

    # Params (default values)
    # -----------------------

    # Setup logging
    log_level=logging.INFO,
    log_config=None,

    # Choose a backend (memory|redis|amqp)
    # memory - is only recommended for testing/local development
    backend='memory',

    # Backend connection params
    # redis: {'url': 'redis://localhost:6379/0', 'channel': 'donald'}
    # amqp: {'url': 'amqp://guest:guest@localhost:5672/', 'queue': 'donald', 'exchange': 'donald'}
    backend_params={},

    # Tasks worker params
    worker_params={
      # Max tasks in work
      'max_tasks': 0,

      # Tasks default params (delay, timeout)
      'task_defaults': {},

      # A awaitable function to run on worker start
      'on_start': None

      # A awaitable function to run on worker stop
      'on_stop': None

      # A awaitable function to run on worker error
      'on_error': None

    },
)

# Wrap a function to task
@manager.task
async def myfunc(*args, **kwargs):
    # Do some job here

# Start the manager somewhere (on app start for example)
await manager.start()

# you may run a worker in the same process
# not recommended for production
worker = manager.create_worker()
worker.start()

# ...

# Submit the task to workers
myfunc.submit(*args, **kwargs)

# ...

# Stop the manager when you need
await worker.stop()
await manager.stop()

Schedule tasks

@tasks.schedule('*/5 * * * *')  # Supports cron expressions, number of seconds, timedelta
@tasks.task
async def myfunc(*args, **kwargs):
    """Run every 5 minutes"""
    # Do some job here


# you may run a scheduler in the same process
# not recommended for production
manager.scheduler.start()

# ...

# Stop the scheduler before stop the tasks manager
manager.scheduler.stop()

Run in production

Create a tasks manager somewhere in your app tasks.py:

manager = Donald(backend='amqp')

# Setup your tasks and schedules.
# See the Quick Start section for details.

Run a worker in a separate process:

$ donald -M tasks:manager worker

Run a scheduler (if you need) in a separate process:

$ donald -M tasks:manager scheduler

Bug tracker

If you have any suggestions, bug reports or annoyances please report them to the issue tracker at https://github.com/klen/donald/issues

Contributing

Development of starter happens at github: https://github.com/klen/donald

License

Licensed under a BSD license.