tasks.py

import logging
from celery import Task
from celery.exceptions import MaxRetriesExceededError
from .app_worker import app
from .yolo import YoloModel


class PredictTask(Task):
    def __init__(self):
        super().__init__()
        self.model = None

    def __call__(self, *args, **kwargs):
        if not self.model:
            logging.info('Loading Model...')
            self.model = YoloModel()
            logging.info('Model loaded')
        return self.run(*args, **kwargs)


@app.task(ignore_result=False, bind=True, base=PredictTask)
def predict_image(self, data):
    try:
        data_pred = self.model.predict(data)
        return {'status': 'SUCCESS', 'result': data_pred}
    except Exception as ex:
        try:
            self.retry(countdown=2)
        except MaxRetriesExceededError as ex:
            return {'status': 'FAIL', 'result': 'max retried achieved'}