<@ULVA73B9P> If I have a `tqdm` style progress bar inside a flow with `log_prints` set as true, wou...
t
@Marvin If I have a
tqdm
style progress bar inside a flow with
log_prints
set as true, would the progress bar overflown my logging space? I don't want that, but also the tdqm progress bar is not inside my code, so I am not sure if I can use the progress artifact to monkey patch it.
m
thought for 332.1 seconds
Short answer: Yes—if
log_prints=True
, tqdm’s updates will be captured as Prefect logs and can spam your logs. tqdm writes to stderr by default and emits frequent carriage-return updates; when captured, these often appear as many log lines. Good ways to prevent log spam without modifying the third‑party code: - Temporarily disable tqdm via environment variable - This works even when the tqdm call is buried in a library. - Wrap just the problematic call:
Copy code
import os
  from contextlib import contextmanager

  @contextmanager
  def disable_tqdm():
      prev = os.environ.get("TQDM_DISABLE")
      os.environ["TQDM_DISABLE"] = "1"
      try:
          yield
      finally:
          if prev is None:
              os.environ.pop("TQDM_DISABLE", None)
          else:
              os.environ["TQDM_DISABLE"] = prev

  with disable_tqdm():
      third_party_fn()
- You can also set this env var in your deployment/worker environment. - Redirect only stderr during the call (tqdm’s default output) - Keeps your other `print`s logged while swallowing the progress bar:
Copy code
from io import StringIO
  from contextlib import redirect_stderr

  with redirect_stderr(StringIO()):
      third_party_fn()
- Temporarily disable Prefect’s print capture - If you’re okay suppressing all print-capture for the block, use:
Copy code
from prefect.logging import disable_run_logger

  with disable_run_logger():
      third_party_fn()
- This will stop Prefect from capturing prints (including tqdm) for the duration of the context, then re-enable logging afterward. - Reduce tqdm’s chattiness (if you want to keep it visible) - Set environment variables to slow down updates:
Copy code
os.environ["TQDM_MININTERVAL"] = "5"   # seconds between refreshes
  os.environ["TQDM_MINiters"] = "100"    # iterations between refreshes
- Docs: tqdm parameters About Prefect progress artifacts - Prefect doesn’t provide an automatic integration to “monkey‑patch” third‑party tqdm bars into artifacts. You’d need to call the artifact APIs yourself from your code. - If you do control the loop, you can replace tqdm with a Progress artifact:
Copy code
from prefect.artifacts import create_progress_artifact, update_progress_artifact

  aid = create_progress_artifact(progress=0, key="my-step", description="Processing items")
  for i, item in enumerate(items, 1):
      # ... work ...
      update_progress_artifact(aid, progress=100 * i / len(items))
- API reference/source: prefect.artifacts Notes - Very chatty output increases run overhead and can make logs hard to navigate in the UI. Prefer one of the suppression approaches above. - Prefect logging docs: Prefect 3 logging API Would you like help wiring one of these wrappers around a specific function where tqdm is being used? If you can share how you call the third‑party code, I can suggest the least invasive option.