What causes "time out" in XX-net/XX-Net?

Increase the timeout argument passed to download_file / download_unzip

XX-net/XX-Net · error · Exception

time out

Error message

time out

What it means

Raised by download_file in gae_proxy's download_gae_lib.py when the total elapsed time of reading the GAE lib download exceeds the caller-supplied timeout before the stream ends. Each loop iteration computes time_left = timeout - elapsed; once negative it throws a generic Exception('time out'). It is a wall-clock deadline applied to the whole HTTP body read, not a per-read socket timeout.

Source

Thrown at code/default/gae_proxy/local/download_gae_lib.py:59

            if not req:
                time.sleep(3)
                continue

            if req.status == 302:
                url = req.headers["Location"]
                continue

            start_time = time.time()
            timeout = 300

            if req.chunked:

                downloaded = 0
                with open(filename, 'wb') as fp:
                    while True:
                        time_left = timeout - (time.time() - start_time)
                        if time_left < 0:
                            raise Exception("time out")

                        dat = req.read(timeout=time_left)
                        if not dat:
                            break

                        fp.write(dat)
                        downloaded += len(dat)

                return True
            else:
                file_size = int(req.getheader('Content-Length', 0))

                left = file_size
                downloaded = 0
                with open(filename, 'wb') as fp:
                    while True:
                        chunk_len = min(65536, left)
                        if not chunk_len:

View on GitHub (pinned to cfa5bc17b6)

Solutions

Increase the timeout argument passed to download_file / download_unzip
Retry the download (transient slowness is common); wrap download_unzip in a retry loop with backoff
Check network/proxy throughput and pause other bandwidth-heavy tasks
If repeatedly timing out at the same byte count, verify the URL still serves the file and isn't hanging

Example fix

// before
download_unzip(url, target_path, timeout=30)
// after
for i in range(3):
    try:
        download_unzip(url, target_path, timeout=300)
        break
    except Exception as e:
        if 'time out' not in str(e) or i == 2:
            raise
        time.sleep(5)

Defensive patterns

Strategy: retry

Try / catch

try:
    download_unzip(url, path, timeout=600)
except Exception as e:
    if 'time out' in str(e):
        # transient: retry with bigger budget
        download_unzip(url, path, timeout=1800)
    else:
        raise

Prevention

Pass a timeout sized to file size over worst-case bandwidth, not best-case
Wrap module downloads in a bounded retry loop with backoff
Monitor elapsed progress so stalls are detected before the hard deadline

When it happens

Trigger: Calling download_file(url, filename, timeout=N) where the server sends data slower than the body can complete in N seconds, or the connection stalls after partial data; also when the file is large and timeout is too small relative to bandwidth.

Common situations: Slow or throttled network to Google/GitHub servers, small hardcoded timeout values, downloading a large archive (e.g. GoAgent lib) over a proxy, temporary server slowness.

Understand the failure class

Timeouts: ETIMEDOUT, deadlines, and hung requests — what actually expires when a request times out.

Related errors

AI-assisted analysis of XX-net/XX-Net@cfa5bc17b6 (2026-08-27). Data as JSON: /api/errors/018905e6004a1c01. Report an issue: GitHub.