treehash.js
treehash.js is a node.js implementation of the SHA256 Tree Hash algorithm, notably used by Amazon Glacier.
For more information, AWS has a good read through: http://docs.amazonwebservices.com/amazonglacier/latest/dev/checksum-calculations.html
Use
npm install treehashCalculate the Tree Hash by loading the entire file into a buffer:
var fs = require('fs');var treehash = require('treehash'); fs.readFile('./lib/treehash.js', function(err, buffer) { var sha = treehash.getTreeHashFromBuffer(buffer) console.log("SHA256 Tree Hash -", sha)})Incrementally calculate a treehash from a file stream:
var fs = require('fs');var treehash = require('treehash'); var thStream = treehash.createTreeHashStream (); var fileStream = fs.createReadStream('./lib/treehash.js');fileStream.on('data', function(chunk) { thStream.update(chunk);}); fileStream.on('end', function (){ var sha = thStream.digest(); console.log("SHA256 Tree Hash -", sha)});