Async Iterators and Generators: Streaming Data in Modern JavaScript
Async iterators let you consume streams of data with for-await-of loops. Here is how I use them for paginated APIs and real-time data. Async iterators are one of the most underused features in modern JavaScript. They let you consume asynchronous streams of data using the same iteration patterns you use for arrays, but each value can arrive asynchronously. After using them to handle paginated APIs, file streams, and real-time data feeds, I find they make async code dramatically more readable than manual promise chains or callback-based event handlers. The for-await-of Loop The for await. of loop is the consumer side of async iteration. It looks like a regular for-of loop, but it awaits each value before continuing. This means the loop body runs sequentially, processing one item fully before moving to the next. For streams where order matters or where processing one item depends on the previous, this is exactly the behavior you want. for await (const chunk of stream) { console.log(chunk); } The loop automatically handles the async iterator protocol, calling the next() method and awaiting the returned promise. You do not need to manage the iteration manually, which eliminates a class…