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q.client.event = Event()
with concurrent.futures.ProcessPoolExecutor() as pool:
    await q.exec(pool, blocking_function, q)

mturoci

q.client.event = Event()
with concurrent.futures.ProcessPoolExecutor() as pool:
    await q.exec(pool, blocking_function, q)

mturoci

if q.args.cancel:
    q.client.event.set()

mturoci

# This takes a lot of time (compute heavy).
async def blocking_function(q: Q):
    count = 0
    total = 20
    while count < total:
        # Check if cancelled.
        if q.client.event.is_set():
            await show_cancel(q)
            return 
        # This blocks the main thread and prevents any other execution.

mturoci

import asyncio
from h2o_wave import main, app, Q, ui


async def polling_function(q: Q):
    count = 0
    total = 10
    while count < total:
        # You would make an async HTTP call here in real-world to get the fresh data.
        await q.sleep(1)

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# Start the polling, wrap in future so that we can cancel it later.
q.client.future = asyncio.ensure_future(polling_function(q))
# Future cancellation raises an error - use trycatch.
try:
    # Wait until polling finished.
    await q.client.future
    q.page['meta'].dialog = None
    q.page['meta'].notification_bar = ui.notification_bar(
        name='success_notification',
        text='Job done!',

mturoci

async def polling_function(q: Q):
    count = 0
    total = 20
    while count < total:
        # You would make an async HTTP call here in real-world to get the fresh data.
        await q.sleep(1)
        count +=1
        q.page['meta'].dialog.items[0].progress.value = count / total
        await q.page.save()

mturoci

import asyncio
import time
import concurrent.futures
from threading import Event
from h2o_wave import main, app, Q, ui


# This takes a lot of time (compute heavy).
def blocking_function(q: Q, loop: asyncio.AbstractEventLoop):
    count = 0

mturoci

if q.args.cancel:
    q.client.event.set()

mturoci

# Do not run like this - will block the whole thread - freeze the app.
# blocking_function(q, loop)

# Get the current event loop - will be used for
# running async functions within the blocking.
loop = asyncio.get_event_loop()
# Create an event to use for cancellation.
q.client.event = Event()
with concurrent.futures.ThreadPoolExecutor() as pool:
    await q.exec(pool, blocking_function, q, loop)