asyncio-programming_skill

Overview

This skill teaches asynchronous programming in Python using asyncio, async/await, and related async libraries. It focuses on writing concurrent I/O-bound code, building async web services, and managing tasks, timeouts, and errors for reliable production systems. Practical examples and hands-on projects reinforce concepts for real-world use.

How this skill works

The curriculum inspects core asyncio primitives: coroutines, the event loop, tasks, and TaskGroup patterns. It demonstrates async I/O with aiohttp, aiofiles, and async database drivers, and shows how to structure async web apps (FastAPI, aiohttp) and WebSocket services. Each topic includes examples for creating, running, cancelling, and debugging concurrent work, plus project-based exercises to apply the techniques.

When to use it

• When your application is I/O-bound and needs high concurrency with low thread overhead
• When building async web APIs, WebSocket servers, or background workers
• When performing concurrent file, HTTP, or database operations
• When you need non-blocking integrations with message brokers or external services
• When reducing latency by running many independent network calls concurrently

Best practices

• Favor async libraries end-to-end to avoid blocking the event loop (use aiohttp, aiofiles, asyncpg)
• Use asyncio.create_task and TaskGroup to manage background work and ensure proper cancellation/cleanup
• Prefer asyncio.gather(return_exceptions=True) or wait for structured error handling in concurrent tasks
• Apply timeouts and retries around external calls to avoid stuck tasks
• Test and debug async flows with dedicated tools (aiodebug) and write integration tests that run the event loop

Example use cases

• Concurrent web scraper that respects rate limits and retries failed requests (aiohttp + async DB)
• Realtime chat server using WebSockets and connection management with aiohttp or FastAPI
• Async task queue with Redis/RabbitMQ workers, graceful shutdown, and progress tracking
• High-throughput API gateway that proxies many backend services concurrently
• Background jobs and notification senders that run without blocking request handlers