@guanghechen/helper-stream

Utilities for handing node streams.

Install

• npm

  npm install --save @guanghechen/helper-stream

• yarn

  yarn add @guanghechen/helper-stream

Usage

Name	Description
concatStreams	Concatenate readable streams to async iterator.
consumeStream	Consume readable stream.
consumeStreams	Consume Consume multiple streams serially.
mergeStreams	Merge multiple readable streams into one readable streams.
stream2buffer	Consume read stream and encode the contents into buffer.

Example

• Basic.

  import { consumeStreams } from '@guanghechen/helper-stream'
  import fs from 'node:fs'
  
  const filepaths = ['a.txt', 'b.txt', 'c.txt']
  const readers: NodeJS.ReadableStream[] = plainFilepaths.map(fp => fs.createReadStream(fp))
  const writer: NodeJS.WritableStream = fs.createWriteStream('out.txt')
  await consumeStreams(readers, writer)

• Middlewares, i.e., cipher data before output.

  import { consumeStreams } from '@guanghechen/helper-stream'
  import crypto from 'crypto'
  import fs from 'node:fs'
  
  const filepaths = ['a.txt', 'b.txt', 'c.txt']
  const readers: NodeJS.ReadableStream[] = plainFilepaths.map(fp => fs.createReadStream(fp))
  const writer: NodeJS.WritableStream = fs.createWriteStream('out.txt')
  
  const iv: Buffer = crypto.randomBytes(32)
  const key: Buffer = crypto.randomBytes(32)
  const cipher: crypto.Cipher = crypto.createCipheriv('aes-256-gcm', key, iv)
  await consumeStreams(readers, writer, cipher)