All 10 Async Iterators & Streams questions
More in Async Iterators & Streams
How do you loop over an async iterable? How do you write an async generator function? What is the ReadableStream API used for? What does return() do on an async iterator? How do you run multiple async iterators concurrently and merge their results? What's the difference between piping streams with pipeThrough() and pipeTo()? Why might Promise.all() be the wrong tool when consuming many async iterators? How do you add a timeout to an async iterator's next() call?
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JavaScript › Async Iterators & Streams

How do you convert a Node.js Readable stream into an async iterable?

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Answer

Modern Node.js Readable streams already implement Symbol.asyncIterator directly, so you can for-await-of over them without any extra wrapping.
const fs = require('fs');
async function readFile() {
  const stream = fs.createReadStream('data.txt');
  for await (const chunk of stream) {
    console.log(chunk.toString());
  }
}
Real-world example Processing a large log file line-by-line without loading the whole file into memory.

Common follow-ups: How would you handle backpressure when the consumer is slower than the source?

Memory Management & Garbage Collection
All 10 Async Iterators & Streams questions