celerylog.py

import argparse
import logging

from celery import Celery
from celery.utils.log import get_task_logger
from flask import Flask, jsonify

app = Flask(__name__)
c = Celery(__name__, broker='amqp://localhost:5672//')
default_logger = c.log.get_default_logger()
log = get_task_logger(__name__)

@c.task
def f(x):
    log.info('Got x = %s', x)
    return x + 1

@app.route('/')
def index():
    result = f.delay(1)
    return jsonify(id=result.id)

def configure_logging(logger):
    log_level = logging.INFO

    formatter = logging.Formatter('%(asctime)s %(levelname)s %(message)s')
    stream_handler = logging.StreamHandler()
    stream_handler.setLevel(log_level)
    stream_handler.setFormatter(formatter)

    logger.addHandler(stream_handler)
    logger.setLevel(log_level)

if __name__ == '__main__':
    configure_logging(default_logger)
    #configure_logging(log) 
    # When I don't configure log, task logger, I don't get log line for the task, Got x = ...
    # When I configure task logger, I get the following duplicate logs:
    # 2015-10-16 17:21:43,958 INFO Got x = 1
    # [2015-10-16 17:21:43,958: INFO/Worker-1] __main__.f[221221cf-bdba-4854-ab49-17cad2530189]: Got x = 1

    parser = argparse.ArgumentParser()
    parser.add_argument('cmd', choices=['server', 'worker'])
    args = parser.parse_args()


    if args.cmd == 'server':
        app.run()
    elif args.cmd == 'worker':
        c.worker_main(argv=[__file__])