celery 入门

认识

这里有几个概念，task、worker、broker。
顾名思义，task 就是老板交给你的各种任务，worker 就是你手下干活的人员。

那什么是 Broker 呢？

老板给你下发任务时，你需要 把它记下来， 这个它 可以是你随身携带的本子，也可以是 电脑里地记事本或者excel，或者是你的 任何时间管理工具。

Broker  则是 Celery 记录task的地方。
作为一个任务管理者的你，将老板（前端程序）发给你的 安排的工作（Task） 记录到你的本子（Broker）里。接下来，你就安排你手下的IT程序猿们（Worker），都到你的本子(Broker)里来取走工作（Task）

1. broker为rabbitmq

#tasks.py

from celery import Celery

app = Celery('tasks', broker='amqp://admin:admin@localhost:5672')

@app.task
def add(x, y):
    return x + y

启动

celery -A tasks worker --loglevel=info

运行

>>> from tasks import add
>>> add(, )

>>> add.delay(,)
<AsyncResult: 07614cef-f314-4c7b-a33f-92c080cadb83>
>>> 

注：delay是使用异步的方式，会压入到消息队列。否则，不会使用消息队列。

文件名为tasks.py，则其中代码app = Celery('tasks', broker=)，Celery第一个参数为工程名，启动时也是celery -A tasks worker --loglevel=info

对比

注：投入到指定的队列用：add.delay(1, 3, queue='queue_add1')

test_2.py

from celery import Celery

app = Celery('proj', broker='amqp://admin:admin@localhost:5672'， include='test_2')

@app.task
def add(x, y):
    return x + y

2. 以python+文件名的方式启动

例1：

#test.py

from celery import Celery
import time
app = Celery('test', backend='amqp', broker='amqp://admin:admin@localhost:5672')

@app.task
def add(x, y):
    print "------>"
    time.sleep(5)
    print "<--------------"
    return x + y

if __name__ == "__main__":
    app.start()

启动

python test.py worker 

celery默认启动的worker数为内核个数，如果指定启动个数，用参数-c，例

python test.py worker -c 2

例2：

#test.py

from celery import Celery
import time
app = Celery('test', backend='amqp', broker='amqp://admin:admin@localhost:5672')

@app.task
def add(x, y):
    print "------>"
    time.sleep(2)
    print "<--------------"
    return x + y

if __name__ == "__main__":
    app.start()

#eg.py

from test import *
import time

rev = []
for i in range(3):
    rev.append(add.delay(1,3))

print "len rev:", len(rev)
while 1:
    tag = 1
    for key in rev:
        if not key.ready():
            tag = 0
            time.sleep(1)
            print "sleep 1"
    if tag:
        break
print "_____________________>"

3. broker为redis

#test_redis.py

from celery import Celery
import time
#app = Celery('test_redis', backend='amqp', broker='redis://100.69.201.116:7000')
app = Celery('test_redis', backend='redis', broker='redis://100.69.201.116:7000')

@app.task
def add(x, y):
    print "------>"
    time.sleep(5)
    print "<--------------"
    return x + y

if __name__ == "__main__":
    app.start()

启动

python test_redis.py worker -c 2

测试

from celery import group
from test_redis import *
g = group(add.s(2, 3)).apply_async()
g = group(add.s(2, 3)).apply_async()
g = group(add.s(2, 3)).apply_async()
g = group(add.s(2, 3)).apply_async()
g = group(add.s(2, 3)).apply_async()
for ret in g.get():
    print ret
print "end-----------------------------------"

结果

5
end-----------------------------------

4. 两个队列(redis)

#test_redis.py

from celery import Celery
import time
#app = Celery('test_redis', backend='amqp', broker='redis://100.69.201.116:7000')
app = Celery('test_redis', backend='redis', broker='redis://100.69.201.116:7000')

@app.task
def add(x, y):
    print "------>"
    time.sleep(5)
    print "<--------------"
    return x + y

if __name__ == "__main__":
    app.start()

#test_redis_2.py

from celery import Celery
import time
#app = Celery('test_redis', backend='amqp', broker='redis://100.69.201.116:7000')
app = Celery('test_redis_2', backend='redis', broker='redis://100.69.201.116:7001')

@app.task
def add_2(x, y):
    print "=======>"
    time.sleep(5)
    print "<================="
    return x + y

if __name__ == "__main__":
    app.start()

测试

from celery import group
from test_redis import *
from test_redis_2 import *
ll = [(1,2), (3,4), (5,6)]
g = group(add.s(key[0], key[1]) for key in ll).apply_async()
for ret in g.get():
    print ret
print "end redis_1 -----------------------------------"

ll = [(1,2), (3,4), (5,6)]
g = group(add_2.s(key[0], key[1]) for key in ll).apply_async()
for ret in g.get():
    print ":", ret
print "end redis_2 -----------------------------------"

结果

3
7
11
end redis_1 -----------------------------------
: 3
: 7
: 11
end redis_2 -----------------------------------

5. 两个队列（同一个rabbitmq）

注释：需要提前设置下队列

##例1

#test.py

from celery import Celery
import time
app = Celery('test', backend='amqp', broker='amqp://admin:admin@localhost:5672//')

@app.task
def add(x, y):
    print "------>"
    time.sleep(5)
    print "<--------------"
    return x + y

if __name__ == "__main__":
    app.start()

#test_2.py

from celery import Celery
import time
app = Celery('test_2', backend='amqp', broker='amqp://admin:admin@localhost:5672//hwzh')

@app.task
def add_2(x, y):
    print "=====>"
    time.sleep(5)
    print "<=========="
    return x + y

if __name__ == "__main__":
    app.start()

测试

from celery import group
from test import *
from test_2 import *

ll = [(1,2), (3,4), (7,8)]
g = group(add.s(key[0], key[1]) for key in ll).apply_async()
for ret in g.get():
    print ret

ll = [(1,2), (3,4), (7,8)]
g = group(add_2.s(key[0], key[1]) for key in ll).apply_async()
for ret in g.get():
    print ret

结果

3
7
15
3
7
15

##例2

#test.py

from celery import Celery
import time
app = Celery('test', backend='amqp', broker='amqp://admin:admin@localhost:5672//mq4')

@app.task
def add(x, y):
    print "------>"
    time.sleep(2)
    print "<--------------"
    return x + y

@app.task
def sum(x, y):
    print "------>"
    time.sleep(2)
    print "<--------------"
    return x + y

if __name__ == "__main__":
    app.start()

#eg2.py

from test import *
import time

rev = []
for i in range(3):
    rev.append(add.delay(1,3))

for i in range(3):
    rev.append(sum.delay(1,3))

print "len rev:", len(rev)
while 1:
    tag = 1
    for key in rev:
        if not key.ready():
            tag = 0
            time.sleep(1)
            print "sleep 1"
    if tag:
        break
print "_____________________>"

6. 保存结果

from celery import Celery

app = Celery('tasks', backend='amqp', broker='amqp://admin:admin@localhost')

@app.task
def add(x, y):
    return x + y

启动

celery -A tasks_1 worker --loglevel=info

与前例不同：

- ** ---------- [config]
- ** ---------- .> app: tasks:0x7f8057931810
- ** ---------- .> transport: amqp://admin:**@localhost:5672//
- ** ---------- .> results: amqp

运行

>>> from tasks_1 import add
>>> result = add.delay(, )
>>> result.ready()
True
>>> result.get()

7. 多个队列

from celery import Celery
from kombu import Exchange, Queue
BROKER_URL = 'amqp://admin:admin@localhost//'
app = Celery('tasks', backend='amqp',broker=BROKER_URL)
app.conf.update(
     CELERY_ROUTES={
          "add1":{"queue":"queue_add1"},
          "add2":{"queue":"queue_add2"},
          "add3":{"queue":"queue_add3"},
          "add4":{"queue":"queue_add4"},
        },
)
@app.task
def add1(x, y):
     return x + y

@app.task
def add2(x, y):
     return x + y

@app.task
def add3(x, y):
     return x + y

@app.task
def add4(x, y):
     return x + y

8. 消息路由

文件：tasks.py

from celery import Celery, platforms
import time
import os

app = Celery('proj', broker='amqp://admin:admin@ip:5672',
             include=['tasks']
             )
app.conf.update(
    CELERY_ROUTES={
        'tasks.fun_1': {
            'queue': "q_1"
        },
        'tasks.fun_2': {
            'queue': "q_2"
        }
    }
)
platforms.C_FORCE_ROOT = True 

@app.task
def fun_1(n):
    print "(((((((((((((((func_1", n
    return 1

@app.task
def fun_2(n):
    print n, ")))))))))))))))"
    return 2

if __name__ == "__main__":
    app.start()

启动

python tasks.py worker -c 2 -Q q_1
python tasks.py worker -c 2 -Q q_2

两个消息队列：q_1, q_2，调用示例

>>> from tasks import *
>>> fun_1(1)
(((((((((((((((func_1 1
1
>>> fun_1.delay(1)
<AsyncResult: 528a2ad1-bc16-4bdc-beff-cd166fe3e885>
>>> fun_2.delay(2)
<AsyncResult: ee5881eb-b384-4a39-ba00-08aa8ee53504>

9. woker内启多进程

#tasks.py

from celery import Celery
import time
import multiprocessing as mp

app = Celery('proj', broker='amqp://admin:admin@ip:5672', include="tasks")

def test_func(i):
    print "beg...:", i
    time.sleep(5)
    print "....end:", i
    return i * 5

@app.task
def fun_1(n):
    curr_proc = mp.current_process()
    curr_proc.daemon = False
    p = mp.Pool(mp.cpu_count())
    curr_proc.daemon = True
    for i in range(n):
        p.apply_async(test_func, args=(i,))
    p.close()
    p.join()
    return 1

if __name__ == "__main__":
    app.start()

说明

直接启动多进程是肯定不可以的，因为是守候进程（curr_proc.daemon=True），所以启多进程之前主动设置为非守候进程：curr_proc.daemon=False，启动了以后再设为守候进程

#tasks_callback.py

from celery import Celery
import time
import multiprocessing as mp

app = Celery('proj', broker='amqp://admin:admin@ip:5672', include="tasks_callback")
rev = []
def test_func(i):
    print "beg...:", i
    time.sleep(5)
    print "....end:", i
    return i * 5

def callback_log(rev_val):
    rev.append(rev_val)

@app.task
def fun_1(n):
    print "before rev:", rev
    curr_proc = mp.current_process()
    curr_proc.daemon = False
    p = mp.Pool(mp.cpu_count())
    curr_proc.daemon = True
    for i in range(n):
        p.apply_async(test_func, args=(i,), callback=callback_log)
    p.close()
    p.join()
    print "after rev:", rev
    return 1

if __name__ == "__main__":
    app.start()

10. 常用参数配置

1. CELERYD_PREFETCH_MULTIPLIER

同时预取得消息个数，比如如果CELERYD_PREFETCH_MULTIPLIER=2，那么如果现在对于1个worker，有一个状态是STARTED, 那么可以有2个处于RECEVED状态(如果有的话)，这样就避免了如果消息很多全部分下取，后起来的worker领不到消息的尴尬。

参考代码

from celery import Celery, platforms
import time
import os

app = Celery('proj', broker='amqp://admin:admin@localhost:5672',
             include=['tasks']
             )
app.conf.update(
    CELERYD_PREFETCH_MULTIPLIER=2,
    CELERY_ROUTES={
        'tasks.fun_1': {
            'queue': "q_1"
        },
        'tasks.fun_2': {
            'queue': "q_2"
        }
    }
)
platforms.C_FORCE_ROOT = True

@app.task
def fun_1(n):
    print "(((((((((((((((func_1", n
    time.sleep(20)
    return 1

@app.task
def fun_2(n):
    print n, ")))))))))))))))"
    return 2

调用

>>> from tasks import *
>>> fun_1.delay(3)
<AsyncResult: 609f2216-6785-409e-9f6f-85ae3fcce084>
>>> fun_1.delay(3)
<AsyncResult: 0230b8bd-b237-40ef-bc73-88929f8f8290>
>>> fun_1.delay(3)
<AsyncResult: 8fce172a-93c9-41f8-8c08-377a4363389c>
>>> fun_1.delay(3)

参考：http://windrocblog.sinaapp.com/?p=1585