Function pipeline

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

await pipeline(
  createReadStream('archive.tar'),
  createGzip(),
  createWriteStream('archive.tar.gz'),
);
console.log('Pipeline succeeded.');
Copy

To use an AbortSignal, pass it inside an options object, as the last argument. When the signal is aborted, destroy will be called on the underlying pipeline, with an AbortError.

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

const ac = new AbortController();
const { signal } = ac;
setImmediate(() => ac.abort());
try {
  await pipeline(
    createReadStream('archive.tar'),
    createGzip(),
    createWriteStream('archive.tar.gz'),
    { signal },
  );
} catch (err) {
  console.error(err); // AbortError
}
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The pipeline API also supports async generators:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';

await pipeline(
  createReadStream('lowercase.txt'),
  async function* (source, { signal }) {
    source.setEncoding('utf8');  // Work with strings rather than `Buffer`s.
    for await (const chunk of source) {
      yield await processChunk(chunk, { signal });
    }
  },
  createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

Remember to handle the signal argument passed into the async generator. Especially in the case where the async generator is the source for the pipeline (i.e. first argument) or the pipeline will never complete.

import { pipeline } from 'node:stream/promises';
import fs from 'node:fs';
await pipeline(
  async function* ({ signal }) {
    await someLongRunningfn({ signal });
    yield 'asd';
  },
  fs.createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

The pipeline API provides callback version:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

await pipeline(
  createReadStream('archive.tar'),
  createGzip(),
  createWriteStream('archive.tar.gz'),
);
console.log('Pipeline succeeded.');
Copy

To use an AbortSignal, pass it inside an options object, as the last argument. When the signal is aborted, destroy will be called on the underlying pipeline, with an AbortError.

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

const ac = new AbortController();
const { signal } = ac;
setImmediate(() => ac.abort());
try {
  await pipeline(
    createReadStream('archive.tar'),
    createGzip(),
    createWriteStream('archive.tar.gz'),
    { signal },
  );
} catch (err) {
  console.error(err); // AbortError
}
Copy

The pipeline API also supports async generators:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';

await pipeline(
  createReadStream('lowercase.txt'),
  async function* (source, { signal }) {
    source.setEncoding('utf8');  // Work with strings rather than `Buffer`s.
    for await (const chunk of source) {
      yield await processChunk(chunk, { signal });
    }
  },
  createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

Remember to handle the signal argument passed into the async generator. Especially in the case where the async generator is the source for the pipeline (i.e. first argument) or the pipeline will never complete.

import { pipeline } from 'node:stream/promises';
import fs from 'node:fs';
await pipeline(
  async function* ({ signal }) {
    await someLongRunningfn({ signal });
    yield 'asd';
  },
  fs.createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

The pipeline API provides callback version:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

await pipeline(
  createReadStream('archive.tar'),
  createGzip(),
  createWriteStream('archive.tar.gz'),
);
console.log('Pipeline succeeded.');
Copy

To use an AbortSignal, pass it inside an options object, as the last argument. When the signal is aborted, destroy will be called on the underlying pipeline, with an AbortError.

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

const ac = new AbortController();
const { signal } = ac;
setImmediate(() => ac.abort());
try {
  await pipeline(
    createReadStream('archive.tar'),
    createGzip(),
    createWriteStream('archive.tar.gz'),
    { signal },
  );
} catch (err) {
  console.error(err); // AbortError
}
Copy

The pipeline API also supports async generators:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';

await pipeline(
  createReadStream('lowercase.txt'),
  async function* (source, { signal }) {
    source.setEncoding('utf8');  // Work with strings rather than `Buffer`s.
    for await (const chunk of source) {
      yield await processChunk(chunk, { signal });
    }
  },
  createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

Remember to handle the signal argument passed into the async generator. Especially in the case where the async generator is the source for the pipeline (i.e. first argument) or the pipeline will never complete.

import { pipeline } from 'node:stream/promises';
import fs from 'node:fs';
await pipeline(
  async function* ({ signal }) {
    await someLongRunningfn({ signal });
    yield 'asd';
  },
  fs.createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

The pipeline API provides callback version:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

await pipeline(
  createReadStream('archive.tar'),
  createGzip(),
  createWriteStream('archive.tar.gz'),
);
console.log('Pipeline succeeded.');
Copy

To use an AbortSignal, pass it inside an options object, as the last argument. When the signal is aborted, destroy will be called on the underlying pipeline, with an AbortError.

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

const ac = new AbortController();
const { signal } = ac;
setImmediate(() => ac.abort());
try {
  await pipeline(
    createReadStream('archive.tar'),
    createGzip(),
    createWriteStream('archive.tar.gz'),
    { signal },
  );
} catch (err) {
  console.error(err); // AbortError
}
Copy

The pipeline API also supports async generators:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';

await pipeline(
  createReadStream('lowercase.txt'),
  async function* (source, { signal }) {
    source.setEncoding('utf8');  // Work with strings rather than `Buffer`s.
    for await (const chunk of source) {
      yield await processChunk(chunk, { signal });
    }
  },
  createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

Remember to handle the signal argument passed into the async generator. Especially in the case where the async generator is the source for the pipeline (i.e. first argument) or the pipeline will never complete.

import { pipeline } from 'node:stream/promises';
import fs from 'node:fs';
await pipeline(
  async function* ({ signal }) {
    await someLongRunningfn({ signal });
    yield 'asd';
  },
  fs.createWriteStream('uppercase.txt'),
);
console.log('Pipeline succeeded.');
Copy

The pipeline API provides callback version:

import { pipeline } from 'node:stream/promises';
import { createReadStream, createWriteStream } from 'node:fs';
import { createGzip } from 'node:zlib';

await pipeline(
  createReadStream('archive.tar'),
  createGzip(),
  createWriteStream('archive.tar.gz'),
);
console.log('Pipeline succeeded.');
Copy