README.rst

Flask-RQ

RQ (Redis Queue) integration for Flask applications

Resources

• Documentation
• Issue Tracker
• Code
• Development Version

Installation

$ pip install flask-rq

Getting started

To quicly start using rq, simply create an RQ instance:

from flask import Flask
form flask.ext.rq import RQ


app = Flask(__name__)

RQ(app)

@job decorator

Provides a way to quickly set a function as an rq job:

from flask.ext.rq import job


@job
def process(i):
    #  Long stuff to process


process.delay(3)

A specific queue name can also be passed as argument:

@job('low')
def process(i):
    #  Long stuff to process


process.delay(2)

Sometimes you need to access application configuration context in your job. There is special way to be able to work inside of context. Please note this is not the same context. This is new, specially created context with the same configuration, but without blueprints or extensions that you probably expect. For example after long task you want to send email with result report:

@job()
def context_process():

    #  Long stuff to process

    from flask import current_app
    from flask.ext.mail import Mail, Message
    mail = Mail()
    # current_app.config is almost the same as in Flask application
    # that call your code 
    mail.init_app(current_app)  
    msg = Message("Report",
              sender="from@example.com",
              recipients=["to@example.com"])
    mail.send(msg)


# inside of your view

@app.route('/make_long_report')
def report(project_id):
    context_process.ctx_delay()
    return 'Check your inbox in few minutes!'

If you need to differentiate contexts then name of Flask application inside of worker job is worker.

get_queue function

Returns default queue or specific queue for name given as argument:

from flask.ext.rq import get_queue


job = get_queue().enqueue(stuff)  # Creates a job on ``default`` queue
job = get_queue('low').enqueue(stuff)  # Creates a job on ``low`` queue

get_worker function

Returns a worker for default queue or specific queues for names given as arguments:

from flask.ext.rq import get_worker


# Creates a worker that handle jobs in ``default`` queue.
get_worker().work(True)
# Creates a worker that handle jobs in both ``default`` and ``low`` queues.
get_worker('default', 'low').work(True)
# Note: These queues have to share the same connection

Configuration

By default Flask-RQ will connect to the default, locally running Redis server. One can change the connection settings for the default server like so:

app.config['RQ_DEFAULT_HOST'] = 'somewhere.com'
app.config['RQ_DEFAULT_PORT'] = 6479
app.config['RQ_DEFAULT_PASSWORD'] = 'password'
app.config['RQ_DEFAULT_DB'] = 1

Queue connection can also be set using a DSN:

app.config['RQ_LOW_URL'] = 'redis://localhost:6379/2'