stream-promise

Convert any Stream instance to thenable

So it can be consumed both as a promise and as a stream

Installation

1npm install stream-promise

Usage

Stream must be either readable or writable.

In case of readable streams, promise resolves with concatenated output, in case of writable streams resolve with undefined

To achieve expected result stream should be converted immediately after initialization.

1const streamPromise = require("stream-promise");
2
3streamPromise(someReadableStream);
4
5someReadableStream.then(result => { console.log("Concatenated stream output", result); });
6
7streamPromise(someWritabletream);
8
9someReadableStream.then(result => { console.log("Cumulated stream output", result); });

Already emitted data is accessible at emittedData property

Non-destructive way

Sepearate promise (without touching stream object) can be created with to-promise util:

1const streamToPromise = require("stream-promise/to-promise");
2
3const someReadableStreamPromise = streamPromiseTo(someReadableStream);
4
5someReadableStreamPromise.then(result => { console.log("Concatenated stream output", result); });

Supported options

noCollect boolean (default: false)

Applicable to readable streams. Set to true, if it's not intended to gather stream result and resolve with it.

Then the only purpose of promise would be to indicate a moment when data stream is finalized

Tests

1npm test