# sha
Check and get file hashes (using any algorithm)
[](https://travis-ci.org/ForbesLindesay/sha)
[](https://gemnasium.com/ForbesLindesay/sha)
[](http://badge.fury.io/js/sha)
## Installation
$ npm install sha
## API
### check(fileName, expected, [options,] cb) / checkSync(filename, expected, [options])
Asynchronously check that `fileName` has a "hash" of `expected` . The callback will be called with either `null` or an error (indicating that they did not match).
Options:
- algorithm: defaults to `sha1` and can be any of the algorithms supported by `crypto.createHash`
### get(fileName, [options,] cb) / getSync(filename, [options])
Asynchronously get the "hash" of `fileName` . The callback will be called with an optional `error` object and the (lower cased) hex digest of the hash.
Options:
- algorithm: defaults to `sha1` and can be any of the algorithms supported by `crypto.createHash`
### stream(expected, [options])
Check the hash of a stream without ever buffering it. This is a pass through stream so you can do things like:
```js
fs.createReadStream('src')
.pipe(sha.stream('expected'))
.pipe(fs.createWriteStream('dest'))
```
`dest` will be a complete copy of `src` and an error will be emitted if the hash did not match `'expected'` .
Options:
- algorithm: defaults to `sha1` and can be any of the algorithms supported by `crypto.createHash`
## License
You may use this software under the BSD or MIT. Take your pick. If you want me to release it under another license, open a pull request.
