Ensure Deterministic Builds (#845)

* add klaw-sync dep, add postbuild script

* specify exact klaw-sync version

package.json

@@ -89,6 +89,7 @@
     "husky": "0.14.3",
     "image-webpack-loader": "3.4.2",
     "jest": "22.1.1",
+    "klaw-sync": "3.0.2",
     "less": "2.7.3",
     "less-loader": "4.0.5",
     "lint-staged": "6.0.0",
@@ -130,6 +131,7 @@
     "db": "nodemon ./db",
     "build": "rimraf dist && webpack --config webpack_config/webpack.prod.js",
     "prebuild": "check-node-version --package",
+    "postbuild": "node ./utils/postBuild.js",
     "build:downloadable": "BUILD_DOWNLOADABLE=true rimraf dist && webpack --config webpack_config/webpack.prod.js",
     "prebuild:demo": "check-node-version --package",
     "test:coverage": "jest --config=jest_config/jest.config.json --coverage",

utils/postBuild.js

@@ -0,0 +1,46 @@
+
+/**
+ * (1) Parses the '.cache' file in the 'dist/icons' folder
+ * (2) Sorts the 'cache.result.files' property
+ * (3) Rewrites the file to ensure a deterministic build
+ */
+
+ 
+const fs = require('fs')
+const path = require('path')
+const klawSync = require('klaw-sync')
+
+const DIST_PATH = path.resolve('./dist/')
+const CACHE_FILE_REGEX = /.*icons-[a-z0-9]*\/\.cache$/
+
+const findCacheFile = item => CACHE_FILE_REGEX.test(item.path)
+
+console.log('postBuild start')
+
+try {
+  const cacheFilePaths = klawSync(DIST_PATH, { filter: findCacheFile })
+
+  if (!cacheFilePaths.length) {
+    throw new Error('Could not find .cache file')
+  }
+
+  if (cacheFilePaths.length > 1) {
+    throw new Error('More than one possible .cache file detected')
+  }
+
+  const cacheFilePath = cacheFilePaths[0].path
+  const rawCacheFile = fs.readFileSync(cacheFilePath, 'utf8')
+  const cache = JSON.parse(rawCacheFile)
+
+  cache.result.files = cache.result.files.sort()
+
+  fs.writeFileSync(cacheFilePath, JSON.stringify(cache), 'utf8')
+
+} catch(err) {
+  console.log('postBuild fail', err)
+  process.exit(1)
+}
+
+console.log('postBuild finish')
+
+