1

I am trying to implement a large file upload in flask using celery. I have a function that saves the file stream to the disk as a celery task but, my implementation requires the use of the request context inside of my task function. I have done my research and implemented the solutions provided on the links given on this answer but, this doesn't seem to work with my version of celery which is 4.1.0

Here is what I am doing

This is my task

@task(name="app.save_operation")
def save_operation():
    content = request.files["content"]
    content.save(
        content.filename)
    content.stream.close()
    return

This is the @task wrapper

def task(**kwargs):
    def decorator(func):
        @celery_helper.task(**kwargs)
        @functools.wraps(func)
        def wrapped(*args, **kwargs):
            with app.test_request_context():
                return func(*args, **kwargs)
        return wrapped
    return decorator

And this is the API handler function where I am calling this task

@app.route("/upload", methods=["GET", "POST"])
def upload():
    if (request.method == "POST"):
        filename = request.files["content"].filename
        task_id = save_operation.delay()
        return "upload started for "+filename

`` This should work fine in theory but, when I do this, celery throws a BadRequestKeyError which essentially means that the request object which is being referred in the save_operation() task is not being passed properly. I am not able to figure out why this is happening and I have reached a roadblock with my research.

I would really like some insights on this.

VimalSheoran
  • 55
  • 4
  • 2
    Isn't it possible to just pass `request` (or its components) as arguments when calling `save_operation.delay()`? Instead of relying on the Flask context. – Tomáš Linhart Mar 20 '19 at 10:28
  • 1
    @TomášLinhart the thing is that the `.delay()` only accepts `json` values and I am able to serialize the `request` object using `jsonpickle` but, when I try to de-serialize it, it throws a runtime error. – VimalSheoran Mar 21 '19 at 08:17

0 Answers0