Add a simple script to generate SRI hashes for our assets. (#24814)

build/generate-sri.js

@@ -0,0 +1,61 @@
+#!/usr/bin/env node
+
+/*!
+ * Script to generate SRI hashes for use in our docs.
+ * Remember to use the same vendor files as the CDN ones,
+ * otherwise the hashes won't match!
+ *
+ * Copyright 2017 The Bootstrap Authors
+ * Copyright 2017 Twitter, Inc.
+ * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
+ */
+
+'use strict'
+
+const fs = require('fs')
+const path = require('path')
+const sriToolbox = require('sri-toolbox')
+const sh = require('shelljs')
+const sed = sh.sed
+
+sh.config.fatal = true
+
+const configFile = path.join(__dirname, '..', '_config.yml')
+
+// Array of objects which holds the files to generate SRI hashes for.
+// `file` is the path from the root folder
+// `configPropertyName` is the _config.yml variable's name of the file
+const files = [
+  {
+    file: 'dist/css/bootstrap.min.css',
+    configPropertyName: 'css_hash'
+  },
+  {
+    file: 'dist/js/bootstrap.min.js',
+    configPropertyName: 'js_hash'
+  },
+  {
+    file: 'assets/js/vendor/jquery-slim.min.js',
+    configPropertyName: 'jquery_hash'
+  },
+  {
+    file: 'assets/js/vendor/popper.min.js',
+    configPropertyName: 'popper_hash'
+  }
+]
+
+files.forEach((file) => {
+  fs.readFile(file.file, 'utf8', (err, data) => {
+    if (err) {
+      throw err
+    }
+
+    const integrity = sriToolbox.generate({
+      algorithms: ['sha384']
+    }, data)
+
+    console.log(`${file.configPropertyName}: ${integrity}`)
+
+    sed('-i', new RegExp(`(\\s${file.configPropertyName}:\\s+"|')(\\S+)("|')`), '$1' + integrity + '$3', configFile)
+  })
+})