How to pipe streams in Node.js

Short answer

Use the .pipe() method on a readable stream to pass its output directly into a writable stream, handling backpressure automatically.

Steps

1. Create a readable stream: const readable = fs.createReadStream('source.txt');.
2. Create a writable stream: const writable = fs.createWriteStream('dest.txt');.
3. Pipe them together: readable.pipe(writable);.
4. Handle errors on the source stream: readable.on('error', console.error);.
5. For transform streams like compression, chain pipes: readable.pipe(gzip).pipe(writable);.

Tips

• pipeline() from the stream module is a modern, promise-friendly alternative that properly cleans up and propagates errors.
• Piping handles backpressure automatically by pausing the readable when the writable buffer is full.

Common issues

• Errors on the writable stream are not automatically forwarded from the readable; use pipeline() or manual error listeners.
• Calling .pipe() after the readable has already emitted end will not write any data.