mirror of https://github.com/peter4431/rq.git
You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
87 lines
2.4 KiB
Markdown
87 lines
2.4 KiB
Markdown
# WARNING: DON'T USE THIS IN PRODUCTION (yet)
|
|
|
|
# rq — Simple job queues for Python
|
|
|
|
**rq** is a lightweight Python job queue, based on Redis.
|
|
|
|
|
|
# Putting jobs on queues
|
|
|
|
To put jobs on queues, first declare a Python function to be called on
|
|
a background process:
|
|
|
|
def slow_fib(n):
|
|
if n <= 1:
|
|
return 1
|
|
else:
|
|
return slow_fib(n-1) + slow_fib(n-2)
|
|
|
|
Notice anything? There's nothing special about a job! Any Python function can
|
|
be put on an RQ queue, as long as the function is in a module that is
|
|
accessible from the worker process.
|
|
|
|
To calculate the 36th Fibonacci number in the background, simply do this:
|
|
|
|
from rq import Queue
|
|
from fib import slow_fib
|
|
|
|
# Calculate the 36th Fibonacci number in the background
|
|
q = Queue()
|
|
q.enqueue(slow_fib, 36)
|
|
|
|
If you want to put the work on a specific queue, simply specify its name:
|
|
|
|
q = Queue('math')
|
|
q.enqueue(slow_fib, 36)
|
|
|
|
You can use any queue name, so you can quite flexibly distribute work to your
|
|
own desire. Common patterns are to name your queues after priorities (e.g.
|
|
`high`, `medium`, `low`).
|
|
|
|
|
|
# The worker
|
|
|
|
**NOTE: You currently need to create the worker yourself, which is extremely
|
|
easy, but RQ will create a custom script soon that can be used to start
|
|
arbitrary workers without writing any code.**
|
|
|
|
Creating a worker daemon is also extremely easy. Create a file `worker.py`
|
|
with the following content:
|
|
|
|
from rq import Queue, Worker
|
|
|
|
q = Queue()
|
|
Worker(q).work_forever()
|
|
|
|
After that, start a worker instance:
|
|
|
|
python worker.py
|
|
|
|
This will wait for work on the default queue and start processing it as soon as
|
|
messages arrive.
|
|
|
|
You can even watch several queues at the same time and start processing from
|
|
them:
|
|
|
|
from rq import Queue, Worker
|
|
|
|
queues = map(Queue, ['high', 'normal', 'low'])
|
|
Worker(queues).work()
|
|
|
|
Which will keep working as long as there is work on any of the three queues,
|
|
giving precedence to the `high` queue on each cycle, and will quit when there
|
|
is no more work (contrast this to the previous worker example, which will wait
|
|
for new work when called with `Worker.work_forever()`.
|
|
|
|
|
|
# Installation
|
|
|
|
Simply use the following command to install the latest released version:
|
|
|
|
pip install rq
|
|
|
|
If you want the cutting edge version (that may well be broken), use this:
|
|
|
|
pip install -e git+git@github.com:nvie/rq.git@master#egg=rq
|
|
|