checksum-stream

checksum-stream is a passthrough stream that calculates the digest and size for data piped through it. Before closing, it will emit digest and size events with the final stream size.

It can also be configured to error if digest or size do not matched a passed-in value that is expected for either or both. size errors will always be emitted first.

Install

$ npm install --save checksum-stream

Example

npm repo

const checksumStream = require('checksum-stream')
const fs = require('fs')
const request = require('request')

let req = request.get('https://npm.im/checksum-stream')
req.on('response', function (res) {
  res.pipe(
    checksumStream({
      algorithm: 'sha256',
      digest: res.headers['etag'],
      size: res.headers['content-length']
    }).on('error', e => throw e)
  ).pipe(
    fs.createWriteStream('./checksum-stream.html')
  )
})