How to use the once function from readable-stream

Find comprehensive JavaScript readable-stream.once code examples handpicked from public code repositorys.

readable-stream.once registers a one-time event listener on a readable stream that will execute the given callback function once when the event is triggered.

ytpl.js

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function endWritable(stream, state, cb) {
  state.ending = true;
  finishMaybe(stream, state);


  if (cb) {
    if (state.finished) process.nextTick(cb);else stream.once('finish', cb);
  }


  state.ended = true;
  stream.writable = false;

bundle.js

GitHub: Zuberkhan56/livestream

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function endWritable(stream, state, cb) {
  state.ending = true;
  finishMaybe(stream, state);
  if (cb) {
    if (state.finished) pna.nextTick(cb);else stream.once('finish', cb);
  }
  state.ended = true;
  stream.writable = false;
}

+ 2 other calls in file

How does readable-stream.once work?

readable-stream.once is a method that adds a one-time listener function for a specific event to a Readable stream, which will execute the listener function at most once the next time the event is triggered.

Ai Example

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const { Readable } = require("stream");

const stream = new Readable({
  read() {},
});

stream.once("data", (chunk) => {
  console.log(`Received chunk: ${chunk}`);
});

stream.push("Hello, world!");

In this example, a new Readable stream is created that overrides the read method with an empty function, effectively creating a "push" stream. The once method is called on the stream with the event type data and a callback function that logs the received chunk to the console. Finally, a chunk is pushed into the stream by calling the push method with the string "Hello, world!". Since the once method was used, the callback function will only be called once with the first data event that is emitted by the stream.