Firebase Update

express-server/node_modules/hash-stream-validation/index.js

@@ -0,0 +1,43 @@
+'use strict'
+
+var crc
+try {
+  crc = require('fast-crc32c')
+} catch (e) {
+  crc = require('./crc32c.js')
+}
+
+var crypto = require('crypto')
+var through = require('through2')
+
+module.exports = function (cfg) {
+  cfg = cfg || {}
+
+  var crc32c = cfg.crc32c !== false
+  var md5 = cfg.md5 !== false
+
+  var hashes = {}
+  if (md5) hashes.md5 = crypto.createHash('md5')
+
+  var onData = function (chunk, enc, done) {
+    if (crc32c) hashes.crc32c = crc.calculate(chunk, hashes.crc32c)
+    if (md5) hashes.md5.update(chunk)
+
+    done(null, chunk)
+  }
+
+  var onFlush = function (done) {
+    if (crc32c) hashes.crc32c = new Buffer([hashes.crc32c]).toString('base64')
+    if (md5) hashes.md5 = hashes.md5.digest('base64')
+
+    done()
+  }
+
+  var validationStream = through(onData, onFlush)
+
+  validationStream.test = function (algo, sum) {
+    return hashes[algo] === sum
+  }
+
+  return validationStream
+}