Hash transform that creates a hash (checksum) from an input stream leaving stream unchanged and is then able to be piped to input of another stream.
hash-transform is written in ecma6 so I would recommend running nodejs v4.0 or greater (no harmony flag needed)
$ npm install hash-transform
$ npm test
new HashTransform(algorithm[, encoding]);
hashing file stream
var HashTransform = ;var path = ;var fs = ;var file = path;var alg = 'sha256';var hash = alg;var fi = fs;fi;hash;