Concurrently

Library helps to easily write concurrent executed code blocks.

Quick example:

import asyncio
from concurrently import concurrently


async def amain(loop):
    """
    How to fetch some web pages with concurrently.
    """
    urls = [  # define pages urls
        'http://test/page_1',
        'http://test/page_2',
        'http://test/page_3',
        'http://test/page_4',
    ]
    results = {}

    # immediately run wrapped function concurrent
    # in 2 thread (asyncio coroutines)
    @concurrently(2)
    async def fetch_urls():
        for url in urls:
            # some function for download page
            page = await fetch_page(url)
            results[url] = page

    # wait until all concurrent threads finished
    await fetch_urls()
    print(results)


if __name__ == '__main__':
    loop = asyncio.get_event_loop()
    loop.run_until_complete(amain(loop))

Decorator @concurrently makes to main thinks:

• starts concurrent execution specified count of decorated function
• returns special waiter object to control the running functions

By default, the code runs as asyncio coroutines, but there are other supported ways to execute, by specifying the argument engine.

Documentation

See https://concurrently.readthedocs.io/

Requirements

Now support only Python 3.5 and above.

Install

From PyPi:

$ pip install concurrently

From local:

# update setuptools
$ pip install 'setuptools >= 30.4'
# do install
$ make install
# or
$ pip install .

Development

Prepare and activate virtual environment like:

$ python3 -m venv .env
# for bash
$ source .env/bin/activate
# for fish
$ . .env/bin/activate.fish

Update pre-install dependencies:

$ pip install 'setuptools >= 30.4'

Install:

$ make install_dev
# or
$ pip install --editable .[develop]

Run tests:

$ make test
# or
$ pytest tests/