Streamx-webstream NPM

streamx-webstream

A wrapper for streamx streams that provides toWeb/fromWeb functions.

Object mode not supported.

Installation

npm install streamx-webstream --save

Import

import { fromWeb, toWeb } from "streamx-webstream";
// or
import { fromWeb } from "streamx-webstream/from";
// or
import { toWeb } from "streamx-webstream/to";
// or CDN
import { fromWeb, toWeb } from "https://esm.run/streamx-webstream";

API

`fromWeb`

Description:

The fromWeb function wraps Web Streams (ReadableStream & WritableStream) and converts them into streamx streams. This is specifically designed for streamx and is not intended for native Node.js streams.

Syntax:

const streamx = fromWeb({ readable, writable });
// or
const streamx = fromWeb(readable);
// or
const streamx = fromWeb(writable);

Parameters:

readable (ReadableStream, optional): The readable stream to be wrapped.
writable (WritableStream, optional): The writable stream to be wrapped.

Returns:

(Streamx.Duplex | Streamx.Readable | Streamx.Writable): A streamx.Duplex stream if both readable and writable streams are provided. A streamx.Readable or streamx.Writable stream if only one is provided.

Example:

import { fromWeb } from "streamx-webstream";
import b4a from "b4a";

const readableWebStream = new ReadableStream({
    start(controller) {
        controller.enqueue(b4a.from("hello"));
        controller.enqueue(b4a.from("world"));
        controller.close();
    }
});

const writableWebStream = new WritableStream({
    write(chunk) {
        console.log('Received chunk:', b4a.toString(chunk));
    }
});

const duplexStreamx = fromWeb({ readable: readableWebStream, writable: writableWebStream });

duplexStreamx.on('data', (chunk) => {
    console.log('Read data:', b4a.toString(chunk));
});

duplexStreamx.write(b4a.from('hello from write'));
duplexStreamx.end();

`toWeb`

Description:

The toWeb function converts streamx streams into Web Streams (ReadableStream & WritableStream). This function is tailored for streamx streams and not for native Node.js streams.

Syntax:

const webStream = toWeb(stream, asBytes);
// or
const webStream = toWeb({ readable: streamxReadable, writable: streamxWritable }, asBytes);

Parameters:

stream (Streamx stream | Object): The streamx stream or an object containing readable, writable, or both to be converted into Web Streams.
asBytes (boolean, optional): Indicates whether the stream should be handled as byte streams. Default is false.

Returns:

(ReadableStream | WritableStream | Object with ReadableStream and/or WritableStream): Returns Web Streams corresponding to the provided streamx stream:
- ReadableStream if the provided streamx stream is readable.
- WritableStream if the provided streamx stream is writable.
- Object containing both ReadableStream and WritableStream if both are provided.

Example:

import { toWeb } from "streamx-webstream";
import { Duplex } from "streamx";
import b4a from 'b4a';

const duplexStreamx = new Duplex({
  read(cb) {
    this.push(b4a.from('Streamx Duplex Readable Data'));
    this.push(null);
    cb();
  },
  write(chunk, cb) {
    console.log('Received duplex chunk:', b4a.toString(chunk));
    cb();
  }
});

const { readable, writable } = toWeb(duplexStreamx);
const reader = readable.getReader();
const writer = writable.getWriter();

reader.read().then(({ value, done }) => {
  if (!done) {
    console.log('Duplex Web Readable data:', b4a.toString(value));
  }
});

writer.write(b4a.from('Streamx Duplex Writable Data')).then(() => writer.close());