Node.js module

stream/promises

The 'node:stream/promises' submodule provides Promise-based stream utility functions such as pipeline and finished, enabling async/await syntax for stream completion and pipeline composition.

Use it to coordinate multiple streams and handle errors cleanly in async code.

function finished(
stream: ReadWriteStream | ReadableStream | WritableStream,
options?: FinishedOptions
): Promise<void>;
function pipeline<A extends PipelineSource<any>, B extends WritableStream | PipelineDestinationIterableFunction<string | Buffer<ArrayBufferLike>> | PipelineDestinationPromiseFunction<string | Buffer<ArrayBufferLike>, any> | PipelineDestinationIterableFunction<any> | PipelineDestinationPromiseFunction<any, any>>(
source: A,
destination: B,
options?: PipelineOptions
): PipelinePromise;
function pipeline<A extends PipelineSource<any>, T1 extends PipelineTransform<A, any>, B extends WritableStream | PipelineDestinationIterableFunction<string | Buffer<ArrayBufferLike>> | PipelineDestinationPromiseFunction<string | Buffer<ArrayBufferLike>, any> | PipelineDestinationIterableFunction<any> | PipelineDestinationPromiseFunction<any, any>>(
source: A,
transform1: T1,
destination: B,
options?: PipelineOptions
): PipelinePromise;
function pipeline<A extends PipelineSource<any>, T1 extends PipelineTransform<A, any>, T2 extends PipelineTransform<T1, any>, B extends WritableStream | PipelineDestinationIterableFunction<string | Buffer<ArrayBufferLike>> | PipelineDestinationPromiseFunction<string | Buffer<ArrayBufferLike>, any> | PipelineDestinationIterableFunction<any> | PipelineDestinationPromiseFunction<any, any>>(
source: A,
transform1: T1,
transform2: T2,
destination: B,
options?: PipelineOptions
): PipelinePromise;
function pipeline<A extends PipelineSource<any>, T1 extends PipelineTransform<A, any>, T2 extends PipelineTransform<T1, any>, T3 extends PipelineTransform<T2, any>, B extends WritableStream | PipelineDestinationIterableFunction<string | Buffer<ArrayBufferLike>> | PipelineDestinationPromiseFunction<string | Buffer<ArrayBufferLike>, any> | PipelineDestinationIterableFunction<any> | PipelineDestinationPromiseFunction<any, any>>(
source: A,
transform1: T1,
transform2: T2,
transform3: T3,
destination: B,
options?: PipelineOptions
): PipelinePromise;
function pipeline<A extends PipelineSource<any>, T1 extends PipelineTransform<A, any>, T2 extends PipelineTransform<T1, any>, T3 extends PipelineTransform<T2, any>, T4 extends PipelineTransform<T3, any>, B extends WritableStream | PipelineDestinationIterableFunction<string | Buffer<ArrayBufferLike>> | PipelineDestinationPromiseFunction<string | Buffer<ArrayBufferLike>, any> | PipelineDestinationIterableFunction<any> | PipelineDestinationPromiseFunction<any, any>>(
source: A,
transform1: T1,
transform2: T2,
transform3: T3,
transform4: T4,
destination: B,
options?: PipelineOptions
): PipelinePromise;
function pipeline(
streams: readonly ReadWriteStream | ReadableStream | WritableStream[],
options?: PipelineOptions
): Promise<void>;
function pipeline(
stream1: ReadableStream,
stream2: ReadWriteStream | WritableStream,
...streams: ReadWriteStream | WritableStream | PipelineOptions[]
): Promise<void>;

Type definitions

interface FinishedOptions
- cleanup?: boolean
  If true, removes the listeners registered by this function before the promise is fulfilled.
- error?: boolean
- readable?: boolean
- signal?: AbortSignal
  When provided the corresponding AbortController can be used to cancel an asynchronous action.
- writable?: boolean

stream/promises

Type definitions

interface FinishedOptions