Reading and writing Node.js streams

あまり使わないけどかなり初歩的なところから解説していたわかりやすかった

Readable

code:stream.js

class MyStream extends Readable {

_read() {

// データ流す ReadableStream Event: 'data'

this.push(':>')

// データ完了 ReadableStream Event: 'end'

this.push(null)

}

}

stream.pause

The readable.pause() method will cause a stream in flowing mode to stop emitting 'data' events, switching out of flowing mode. Any data that becomes available will remain in the internal buffer.

code:pause.js

stream.on("data", (chunk) => {

console.log(chunk.toString());

stream.pause(); // Pause receiving data to simulate processing delay

setTimeout(() => {

stream.resume(); // Resume after 1000ms

}, 1000);

});

stream.on("pause", () => console.log("paused."));

stream.on("end", () => console.log("ended."));

例えば resume しないまま pause 状態になると stream も途切れるっぽい（プロセス終了とみなしているだけか？