Registry / http-networking / asyncio-throttle

asyncio-throttle

library1.0.2pypypi✓ verified 23d ago

asyncio-throttle is a simple, easy-to-use library providing a throttler for asynchronous operations in Python. It's designed to limit the rate at which code blocks can be executed, primarily through an `async with` statement. The current stable version is 1.0.2, released in April 2021. It requires Python 3.6 or later.

http-networking

pip install asyncio-throttle

github ↗package ↗

INSTALL

IMPORT

SIG · ASYNCIO-THROTTLE

asyncio-throttle

http-networkingpythonv1.0.2

Install

1.5s avg

Import

197ms

Disk

16MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v1.0.2 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.95 runs

installs and imports cleanly · install 0.0s · import 0.210s · 17.8MB

glibc

py 3.10–3.95 runs

installs and imports cleanly · install 1.5s · import 0.184s · 18MB

16MB installed

● package 16MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Throttler

✓ from asyncio_throttle import Throttler

This quickstart demonstrates how to use `Throttler` as an asynchronous context manager to limit the rate of operations across multiple concurrent tasks. It creates five workers that each attempt to print a message, but the `Throttler` ensures a maximum of 5 messages are printed per second in total.

import asyncio import time import random from asyncio_throttle import Throttler async def worker(no, throttler, n): for _ in range(n): # Simulate some async work before acquiring the throttle await asyncio.sleep(random.random() * 0.5) async with throttler: # This block will be rate-limited print(f'{time.time():.4f} Worker #{no}: Bang!') async def main(): # Limit to 5 'Bang!' messages per second across all workers throttler = Throttler(rate_limit=5) # Create 5 workers, each trying to 'Bang!' 3 times tasks = [ asyncio.create_task(worker(no, throttler, 3)) for no in range(5) ] await asyncio.gather(*tasks) if __name__ == '__main__': # Ensure to run in an event loop asyncio.run(main())

Debug

Known issues

gotchaForgetting to `await` a coroutine function will create a coroutine object but not schedule or run it, leading to silent failures or unexpected behavior. Always use `await` or `asyncio.create_task()` for coroutines.

fix

Ensure all coroutine calls are `await`ed or scheduled via `asyncio.create_task()`.

affects: All versions

gotchaPerforming blocking I/O operations (e.g., `requests.get()`, `time.sleep()`) directly within an `asyncio` event loop will block the entire loop, negating the benefits of asynchronous programming. Use async-native libraries (e.g., `aiohttp`, `httpx`, `asyncpg`) or offload blocking operations to a thread pool via `loop.run_in_executor()`.

fix

Replace blocking I/O with async equivalents or use `asyncio.to_thread()` (Python 3.9+) / `loop.run_in_executor()` for CPU-bound or blocking tasks.

affects: All versions

gotchaCPU-bound tasks executed directly in the event loop will block all other concurrent tasks. For computationally intensive work, use `loop.run_in_executor()` or `asyncio.to_thread()` (Python 3.9+) to run them in a separate thread or process pool, preventing the event loop from stalling.

fix

Offload CPU-bound work to `asyncio.to_thread()` or `loop.run_in_executor(None, blocking_function, *args)`.

affects: All versions

breakingChanges in `asyncio` implementation in Python 3.14+ may affect environments that relied on `nest_asyncio` for automatic async-to-sync conversion (e.g., Jupyter notebooks). Direct `await` calls for async methods are now often required, and implicit conversions may fail with `RuntimeError`.

fix

Use explicit `await` for all async function calls in affected environments. Avoid `asyncio.run()` in already running event loops.

affects: Python 3.14+

Errors

Common errors & fixes

ImportError: cannot import name 'Throttle' from 'asyncio_throttle'

The class is named 'Throttler', not 'Throttle'.

fix

from asyncio_throttle import Throttler

AttributeError: 'Throttler' object has no attribute 'acquire'

The 'Throttler' class does not have an 'acquire' method; it should be used as an async context manager.

fix

async with throttler:
    # your code here

TypeError: 'Throttler' object is not callable

Attempting to call a 'Throttler' instance directly, which is not supported.

fix

async with throttler:
    # your code here

ModuleNotFoundError: No module named 'asyncio_throttle'

The `asyncio-throttle` package is not installed in the current Python environment, or the environment where it's installed is not activated.

fix

Ensure the library is installed using pip: `pip install asyncio-throttle`. If using a virtual environment, activate it first.

AttributeError: module 'asyncio_throttle' has no attribute 'Throttler'

The `Throttler` class is imported incorrectly. It needs to be imported directly from the package, not accessed as an attribute of the top-level module when a direct import is intended.

fix

Change the import statement from `import asyncio_throttle` to `from asyncio_throttle import Throttler`.

Upgrade

Version history

1.0.2latest on PyPI · released Apr 7, 2021

Audit

Dependencies

No dependency data recorded yet.

Agent activity

24 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/hallazzang/asyncio-throttle ↗

packagehttps://pypi.org/project/asyncio-throttle/ ↗