Async Python: asyncio, Concurrency, and API Patterns
Async Python lets you handle thousands of concurrent I/O operations -- API calls, database queries, file reads -- without threads. The async/await syntax, combined with asyncio's event loop, gives you a clean concurrency model that scales to high-throughput applications. But async code has its own patterns, pitfalls, and debugging challenges that differ from synchronous Python.
This learning path covers async from first principles through production patterns: async/await basics, making concurrent API calls, choosing between gather and TaskGroup, error handling with retries and backoff, connection pooling, streaming responses, and migrating sync codebases to async.
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Python async/await
Core async syntax, coroutines, the event loop, and running your first async code.
Python Coroutines
How coroutines work under the hood, the evolution from generators to native coroutines, and the asyncio runtime.
Python Async API Calls with asyncio and aiohttp
Making non-blocking HTTP requests with aiohttp, session management, and basic concurrency patterns.
Python asyncio.gather for Multiple API Requests
Running multiple API calls concurrently with gather, handling partial failures, and result ordering.
Python asyncio TaskGroup vs gather
Comparing TaskGroup (Python 3.11+) with gather -- error handling, cancellation semantics, and when to use each.
Handle Rate Limits in Async Python with Semaphores
Using asyncio.Semaphore for backpressure and controlled concurrency in high-throughput applications.
Python Connection Pooling
Managing connection pools for HTTP, database, and socket connections in async applications.
Async API Error Handling: Retries, Timeouts, and Backoff
Building robust async code with retry logic, timeout handling, exponential backoff, and circuit breakers.
Build an Async REST API Client with Connection Pooling
Creating a production-grade async API client with session reuse, pooling, and graceful shutdown.
Stream Responses from Async APIs with httpx
Streaming large responses, server-sent events, and chunked transfer handling with httpx.
httpx vs aiohttp for Async API Requests
Feature comparison, performance benchmarks, and choosing between the two major async HTTP libraries.
Convert Sync to Async Python: API Migration Guide
Step-by-step process for migrating synchronous Python code to async, with patterns for mixed codebases.