[Python] Playwright how to detect download events [closed]

I want to download a report from a website using playwright, the structure of the website is like this:

1. Fill in input and click download button
2. Redirect to another page (with a progress bar/ spinner) while waiting for download to finish
3. The time taken to download will depends on the size of the report

The problem I encountered is:

1. I need to download a list of report with different input values
2. For some input values, there is no report, however, the line

$ if download_info:

return true even if there is nothing downloaded (I can see from the chromium browser

1. therefore, the next line

$download =download_info.value

will take forever to run until the end of the timeour

Here is my code:

try:
with page.expect_download(timeout=6000000) as download_info:
print("Step 1: Preparing to click download button")
button.click()
print("Step 2: Clicked Download Report button")

print("Step 3: Waiting for progress spinner to appear...")
page.wait_for_selector('.mat-progress-spinner', timeout=10000)
print("Step 4: Progress spinner detected.")

print("Step 5: Waiting for the spinner to disappear or stop spinning...")
page.evaluate("console.log('Step 5: Waiting for spinner to disappear')")
start_time = datetime.datetime.now()
page.wait_for_function(
"""async () => {
console.log("Inside wait_for_function: Checking spinner...");

// Function to pause for a specified time (1000ms)
function delay(ms) {
return new Promise(resolve => setTimeout(resolve, ms));
}

while (true) {
const spinner = document.querySelector('.mat-progress-spinner');
if (!spinner) {
console.log("Spinner not found.");
return true;
}
const style = window.getComputedStyle(spinner);
console.log("Spinner visibility:", style.display, style.visibility);
if (style.display === 'none' || style.visibility === 'hidden' || spinner.getBoundingClientRect().height === 0) {
console.log("Spinner disappeared or hidden.");
return true;
}

// Pause for 500 milliseconds before the next check
await delay(500);
}
}""",
timeout=6000000 # 5 minutes
)
end_time = datetime.datetime.now()
duration = end_time - start_time
print(f"time taken = {duration}")
print("Step 6: Spinner stopped or disappeared.")
page.evaluate("console.log('Step 6: Spinner stopped or disappeared')")

print("Step 7: Waiting briefly to see if download starts...")

page.wait_for_timeout(1000)

if download_info:
print("download found!!!!")
print("Step 8: Waiting for download event...")
download = download_info.value
print("Step 9: Download event captured")

path = download.path()
if path and os.path.exists(path):
df = pd.read_excel(path)
print("Step 10: File downloaded and read successfully.")
else:
print('Error: download path not found')
return
time.sleep(0.5)
if df is not None:
df = df['csoStatus']
return df
else:
print("Step 000: No download event occurred after spinner stopped.")
return None

except Exception as e:
print(f"Error during download: {e}")
return None



The method I have tried:

1. Conccurent futures, but it does not work because I am using playwright
2. Try to terminate the chunk started with 'if download_info:' but it always stuck at the assignment

I have updated the code to the latest version, thank you

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