hash-stream-validation

> Hash a stream of data, then validate

``sh
$ npm install --save hash-stream-validation
`
`js
var hashStreamValidation = require('hash-stream-validation');

var validateStream = hashStreamValidation();

fs.createReadStream(filePath)
.pipe(validateStream)
.on('data', function() { /... / })
.on('end', function() {
validateStream.test('md5', /checksum/);
});
`

Do this for faster crc32c computation

If the speeds are too slow for your use, this module will try to require fast-crc32c. We chose not to make it an optionalDependency because npm's scary warning output confuses users into thinking their hard drive was just erased.


`js
$ npm install --save fast-crc32c
`

Use Case

After a successful upload to a Google Cloud Storage bucket, the API will respond with the hash of data it has received. During our upload, we can run the data through this module, then confirm after the upload if we both arrived at the same results. If not, we know something went wrong during the transmission.

API

$3

#### opts.crc32c
- Type: Boolean
- Default: true

Enable crc32c hashing via sse4_crc32.*

* Note: Any issues installing this module on your system should be opened at their repository.

#### opts.md5
- Type: Boolean
- Default: true

Enable MD5 hashing.

$3

#### algo
- Type: String

The alogrithm to test the sum against ('crc32c' or 'md5').

#### sum
- Type: String`

The base64-encoded sum to validate.