Async programming allows us to write non-blocking code that doesn't halt execution while waiting on long-running tasks like network requests or file I/O. This makes async ideal for Python web servers, scrapers, and other programs needing high throughput and scalability.
However, async code can get complex with many callback functions and promise-style coding. The async and await keywords introduced in Python 3.5 aim to simplify this.
How async/await Works
An async function is a special type that allows usage of the await keyword and handles concurrency differently:
The await pauses execution until the async operation completes, without halting the program. This makes async code read similarly to synchronous code, while still running concurrently.
Behind the scenes, the asyncio module manages switching between async tasks efficiently.
Key Benefits
More legible and idiomatic Python code
Avoid callback hell - no need to nest functions
Write synchronous-style code while still using non-blocking operations
Integrates well with async libraries like aiohttp
Practical Tips
Use asyncio.run to run async main functions
Handle exceptions properly with try/except blocks
Async code runs on a single thread, so use asyncio.create_task to spawn separate tasks
Use asyncio.gather to wait on multiple async operations
So in summary, async/await makes async programming far more straightforward in Python. The syntax unlocks the power of asynchronous frameworks with code that reads like it's synchronous. This helps developers write highly performant network apps without sacrificing code quality or maintainability.
Browse by tags:
Browse by language:
The easiest way to do Web Scraping
Get HTML from any page with a simple API call. We handle proxy rotation, browser identities, automatic retries, CAPTCHAs, JavaScript rendering, etc automatically for you