brq 0.3.2

brq

This project is inspired by arq. Not intentionally dividing the community, I desperately needed a redis queue based on redis stream for work reasons and just decided to open source it.

You should also consider arq as more of a library: https://github.com/samuelcolvin/arq/issues/437

brq

Prerequisites

Redis >= 6.2, tested with latest redis 6/7 docker image. Recommended to use redis>=7, which includes more inspection features.

Install

pip install brq

Feature

See examples for running examples.

• Defer job and automatic retry error job
• Dead queue for unprocessable job, you can process it later
• Multiple consumers in one consumer group
• No scheduler needed, consumer handles itself

Echo job overview

Producer

import os

from brq.producer import Producer
from brq.tools import get_redis_client, get_redis_url


async def main():
    redis_url = get_redis_url(
        host=os.getenv("REDIS_HOST", "localhost"),
        port=int(os.getenv("REDIS_PORT", 6379)),
        db=int(os.getenv("REDIS_DB", 0)),
        cluster=bool(os.getenv("REDIS_CLUSTER", "false") in ["True", "true", "1"]),
        tls=bool(os.getenv("REDIS_TLS", "false") in ["True", "true", "1"]),
        username=os.getenv("REDIS_USERNAME", ""),
        password=os.getenv("REDIS_PASSWORD", ""),
    )
    async with get_redis_client(redis_url) as async_redis_client:
        await Producer(async_redis_client).run_job("echo", ["hello"])


if __name__ == "__main__":
    import asyncio

    asyncio.run(main())

Consumer

import os

from brq.consumer import Consumer
from brq.daemon import Daemon
from brq.tools import get_redis_client, get_redis_url


async def echo(message):
    print(message)


async def main():
    redis_url = get_redis_url(
        host=os.getenv("REDIS_HOST", "localhost"),
        port=int(os.getenv("REDIS_PORT", 6379)),
        db=int(os.getenv("REDIS_DB", 0)),
        cluster=bool(os.getenv("REDIS_CLUSTER", "false") in ["True", "true", "1"]),
        tls=bool(os.getenv("REDIS_TLS", "false") in ["True", "true", "1"]),
        username=os.getenv("REDIS_USERNAME", ""),
        password=os.getenv("REDIS_PASSWORD", ""),
    )
    async with get_redis_client(redis_url) as async_redis_client:
        daemon = Daemon(Consumer(async_redis_client, echo))
        await daemon.run_forever()


if __name__ == "__main__":
    import asyncio

    asyncio.run(main())

Technical details: deferred jobs

We can use defer_until as a datetime or defer_hours+defer_minutes+defer_seconds to calculate a timestamp based on current redis timestamp. And use unique to set the job to be unique or not.

By default, unique=True means Job with the exactly same function_name, args and kwargs will be unique, which allows the same Job to add into the deferred queue more than once. In this case, we differentiate tasks by the current redis timestamp(Job.create_at) and an additional uuid(Job.uid), just like redis stream did.

If unique=False, the same Job will be added into the deferred queue only once. Duplicates will update the job's defer time. In this case, you can use your own uuid in args(or kwargs) to differentiate Job.

Develop

Install pre-commit before commit

pip install pre-commit
pre-commit install

Install package locally

pip install -e .[test]

Run unit-test before PR

pytest -v