[FIXED] How to make a Python concurrent Future that signals when a list of Futures has completed?

Issue

I have a function that submits several tasks to a ThreadPoolExecutor and return a list of Futures created by each submission:

def submit_tasks() -> [Future]:
    futures = []

    for i in range(10):
        future = executor.submit(Task())
        futures.append(future)

    return futures

def submit() -> Future:
    futures = submit_tasks()
    
    # I would like this function to return a single Future that clients can use to check
    # whether all futures in the list have completed. How to do that?

I'm on Python 3.8

I would like this function to return a single Future that clients can use to check whether all futures in the list have completed. How to do that?

Solution

Use concurrent.futures.wait: https://docs.python.org/3/library/concurrent.futures.html#module-functions

from concurrent.futures import Future, wait

...

def submit() -> Future:
    return wait(submit_tasks())

Answered By - Samwise