A simple module to generate SRI hashes out of files and implement sub-resource integrity
A simple module to generate SRI hashes out of files and
implement sub-resource integrity.
Simply do an npm install --save node-sri and include it
in your code:
`` javascript`
var sri = require('node-sri')
Be aware that you will need to have openssl installed
on the system.
Using the module is pretty straightforward, as you can use it
both with callbacks:
` javascript
var sri = require('node-sri')
sri.hash('/path/to/my/file.js', function(err, hash){
if (err) throw err
console.log('My hash is', hash)
})
`
and, if you fancy, with promises:
` javascript
var sri = require('node-sri')
sri.hash('/path/to/my/file.js').then(function(hash){
console.log('My hash is', hash)
}).catch(function(err){
console.log('ouch!', err)
})
`
By default, it will use sha256 to generate hashes
but you can configure it to use whatever algorithm,
using options rather than a filename as first argument
of the hash function:
` javascript`
sri.hash({file: '/path/to/my/file.js', algo: 'sha512'}) // sha512-z4PhNX7vuL3xVChQ1m2AB9Yg5AULVxXcg/SpIdNs6c5H0NE8XYXysP+DGNKHfuwvY7kxvUdBeoGlODJ6+SfaPg==
Hashes will be prepended with the algorithm (ie. sha256-...) butprefix
you can also use the option to remove the prefix:
` javascript`
sri.hash({file: '/path/to/my/file.js', algo: 'sha512', prefix: false}) // z4PhNX7vuL3xVChQ1m2AB9Yg5AULVxXcg/SpIdNs6c5H0NE8XYXysP+DGNKHfuwvY7kxvUdBeoGlODJ6+SfaPg==
See example.js
or try running it with node example.js:
`
~/projects/node-sri (master ✘)✹ ᐅ node example.js
Generating SRI hash for the package.json...
Generating SRI hash for the README.md...
Generating SRI hash for a file that doesn't exist...
Generating SRI hash for the package.json with SHA512...
Generating SRI hash for the package.json with SHA512 without the prefix...
README.md's hash is sha256-IQW2dfoEDMp/r7nf9Au0lTkTIWYXLLrObNwVO3LUWzc=
package.json's hash is sha256-NsbsCsoAeBPs3qxHKaM6GMX7MfBTuoF+lbI8WWXN+Ys=
package.json's SHA512 hash without the prefix is 5aK2wlSasZymZfq7y2ffJtjFnmkiEZELIWSn0iusYBxJ32pflmCOV3xRfoSBQP/kLQGh/Paqp0Ia7N0EkuhMAA==
package.json's SHA512 hash is sha512-5aK2wlSasZymZfq7y2ffJtjFnmkiEZELIWSn0iusYBxJ32pflmCOV3xRfoSBQP/kLQGh/Paqp0Ia7N0EkuhMAA==
We got this error when generating an SRI hash for a file that doesnt exist: cat: /YOLO!: No such file or directory
After cloning and doing an npm install you cannpm test
simply run and... ...welcome to greenland!
`
~/projects/node-sri (master ✔) ᐅ npm test
> node-sri@1.0.0 test /home/odino/projects/node-sri
> ./node_modules/mocha/bin/mocha
sri
#hash()
✓ should return a promise when called without callback
✓ should return an hash when generating an sri for an existing file
✓ should return an error when generating an sri for a non existing file
✓ should use a callback when passed
✓ should return an hash when generating an sri for an existing file with a callback
✓ should return an error when generating an sri for a non existing file with a callback
6 passing (56ms)
``
* SRI specification
* Github implements sub-resource integrity
* online SRI hash generator