This issue has been discussed before and looking over numerous posts, I am so far unable to find a solution to this problem. I'm new to celery so my learning curve is still fairly steep. Below my current scripts:
myapp.__init__.py
from __future__ import absolute_import, unicode_literals
from .celery_main import app as celery_app # Ensures app is always imported when Django starts so that shared_task will use this app.
__all__ = ['celery_app']
myapp.celery_main.py
from __future__ import absolute_import
from celery import Celery
from django.apps import apps
# Initialise the app
app = Celery()
app.config_from_object('myapp.celeryconfig') # WORKS WHEN CALLED THROUGH VIEW/DJANGO: Tell Celery instance to use celeryconfig module
#app.config_from_object('celeryconfig') # WORKS WHEN CALLED THROUGH TERMINAL
# Load task modules from all registered Django app configs.
app.autodiscover_tasks(lambda: [n.name for n in apps.get_app_configs()])
myapp.celeryconfig.py
from __future__ import absolute_import, unicode_literals
from datetime import timedelta
## List of modules to import when celery starts.
CELERY_IMPORTS = ('celery_tasks',)
## Message Broker (RabbitMQ) settings.
BROKER_URL = 'amqp://'
BROKER_PORT = 5672
## Result store settings.
CELERY_RESULT_BACKEND = 'rpc://'
## Misc
#CELERY_IGNORE_RESULT = False
CELERY_TASK_SERIALIZER = 'json'
CELERY_RESULT_SERIALIZER = 'json'
CELERY_ACCEPT_CONTENT=['json']
CELERY_TIMEZONE = 'Europe/Berlin'
CELERY_ENABLE_UTC = True
CELERYBEAT_SCHEDULE = {
'doctor-every-10-seconds': {
'task': 'celery_tasks.fav_doctor',
'schedule': timedelta(seconds=3),
},
}
myapp.celery_tasks.py
from __future__ import absolute_import
from celery.task import task
suf = lambda n: "%d%s" % (n, {1: "st", 2: "nd", 3: "rd"}.get(n if n < 20 else n % 10, "th"))
@task
def fav_doctor():
# Stuff happend here
@task
def reverse(string):
return string[::-1]
@task
def send_email(user_id):
# Stuff happend here
@task
def add(x, y):
return x+y
anotherapp.settings.py
INSTALLED_APPS = [
...
'kombu.transport.django',
]
myapp.views.admin_scripts.py
from celery.result import AsyncResult
from myapp.celery_tasks import fav_doctor, reverse, send_email, add
from myapp.celery_main import app
@login_required
def admin_script_dashboard(request):
if request.method == 'POST':
form = Admin_Script(request.POST)
if form.is_valid():
# Results
async_result = add.delay(2, 5)
task_id = async_result.task_id
res = AsyncResult(async_result)
res_1 = add.AsyncResult(async_result)
res_2 = add.AsyncResult(async_result.id)
print ("async_result: {0}\ntask_id: {1}\nres: {2}\nres_1: {3}\nres_2: {4}".format(async_result, task_id, res, res_1, res_2))
# Backend: Make sure the client is configured with the right backend
print("Backend check: {0}".format(async_result.backend))
# States/statuses
task_state = res.state
A = async_result.status
B = res.status
print ("task_state: {0}\nA: {1}\nB: {2}".format(task_state, A, B))
The results when triggering the celery workers through my django application (related to the print statements in app.views.admin_scripts.py):
async_result: 00d7ec84-ebdb-4968-9ea6-f20ca2a793b7
task_id: 00d7ec84-ebdb-4968-9ea6-f20ca2a793b7
res: 00d7ec84-ebdb-4968-9ea6-f20ca2a793b7
res_1: 00d7ec84-ebdb-4968-9ea6-f20ca2a793b7
res_2: 00d7ec84-ebdb-4968-9ea6-f20ca2a793b7
Backend check: <celery.backends.rpc.RPCBackend object at 0x106e308d0>
task_state: PENDING
A: PENDING
B: PENDING
Output in Terminal triggered:
[2018-07-15 21:41:47,015: ERROR/MainProcess] Received unregistered task of type 'MyApp.celery_tasks.add'.
The message has been ignored and discarded.
Did you remember to import the module containing this task?
Or maybe you are using relative imports?
Please see <link> for more information.
The full contents of the message body was:
{'task': 'MyApp.celery_tasks.add', 'id': 'b21ffa43-d1f1-4767-9ab8-e58afec3ea0f', 'args': [2, 5], 'kwargs': {}, 'retries': 0, 'eta': None, 'expires': None, 'utc': True, 'callbacks': None, 'errbacks': None, 'timelimit': [None, None], 'taskset': None, 'chord': None} (266b)
Traceback (most recent call last):
File "/Users/My_MBP/anaconda3/lib/python3.6/site-packages/celery/worker/consumer.py", line 465, in on_task_received
strategies[type_](message, body,
KeyError: 'MyApp.celery_tasks.add'
I have several questions:
1. I can trigger the expected results by using commands in Terminal:
celery -A celery_tasks worker -l info
Then in the Python shell:
from celery_tasks import *
add.delay(2,3)
Which succeeds:
[2018-07-13 10:12:14,943: INFO/MainProcess] Received task: celery_tasks.add[c100ad91-2f94-40b1-bb0e-9bc2990ff3bc]
[2018-07-13 10:12:14,961: INFO/MainProcess] Task celery_tasks.add[c100ad91-2f94-40b1-bb0e-9bc2990ff3bc] succeeded in 0.017578680999577045s: 54
So executing the tasks in Terminal works, but not in my view.py in Django, why not?
2. Perhaps related to 1.: I have to, annoyingly, configure in app.celery_main.py the app.config_from_object depending if I want to test via Django, or via Terminal. You can see either I set the celeryconfig.py with myapp name prefixed, or without. Otherwise, an error message is thrown. I suspect some kind of import looping is causing an issue here (though I could be wrong) but I don't know why/where. How can I overcome this?
3. In my settings.py file (not celeryconfig.py) I have configured in INSTALLED_APPS: 'kombu.transport.django'. Is this necessary? I'm using celery 3.1.26.post2 (Cipater)
4. In all my files I have at the top:
from __future__ import absolute_import, unicode_literals
For what purpose is this for exactly and for 3.1.26 is it required?
5. I read here, that you need to ensure the client is configured with the right backend. But I'm not sure exactly what this means. My print out is (as per app.views.admin_scripts.py):
Backend check: <celery.backends.rpc.RPCBackend object at 0x106e308d0>
If there are any abnormalities in my code you recognise, please feel free to let me know.
