WIP - add extractor, generate snippet_data

node_modules/react-dev-utils/FileSizeReporter.js

@@ -0,0 +1,141 @@
+/**
+ * Copyright (c) 2015-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+'use strict';
+
+var fs = require('fs');
+var path = require('path');
+var chalk = require('chalk');
+var filesize = require('filesize');
+var recursive = require('recursive-readdir');
+var stripAnsi = require('strip-ansi');
+var gzipSize = require('gzip-size').sync;
+
+// Prints a detailed summary of build files.
+function printFileSizesAfterBuild(
+  webpackStats,
+  previousSizeMap,
+  buildFolder,
+  maxBundleGzipSize,
+  maxChunkGzipSize
+) {
+  var root = previousSizeMap.root;
+  var sizes = previousSizeMap.sizes;
+  var assets = webpackStats
+    .toJson()
+    .assets.filter(asset => /\.(js|css)$/.test(asset.name))
+    .map(asset => {
+      var fileContents = fs.readFileSync(path.join(root, asset.name));
+      var size = gzipSize(fileContents);
+      var previousSize = sizes[removeFileNameHash(root, asset.name)];
+      var difference = getDifferenceLabel(size, previousSize);
+      return {
+        folder: path.join(path.basename(buildFolder), path.dirname(asset.name)),
+        name: path.basename(asset.name),
+        size: size,
+        sizeLabel: filesize(size) + (difference ? ' (' + difference + ')' : ''),
+      };
+    });
+  assets.sort((a, b) => b.size - a.size);
+  var longestSizeLabelLength = Math.max.apply(
+    null,
+    assets.map(a => stripAnsi(a.sizeLabel).length)
+  );
+  var suggestBundleSplitting = false;
+  assets.forEach(asset => {
+    var sizeLabel = asset.sizeLabel;
+    var sizeLength = stripAnsi(sizeLabel).length;
+    if (sizeLength < longestSizeLabelLength) {
+      var rightPadding = ' '.repeat(longestSizeLabelLength - sizeLength);
+      sizeLabel += rightPadding;
+    }
+    var isMainBundle = asset.name.indexOf('main.') === 0;
+    var maxRecommendedSize = isMainBundle
+      ? maxBundleGzipSize
+      : maxChunkGzipSize;
+    var isLarge = maxRecommendedSize && asset.size > maxRecommendedSize;
+    if (isLarge && path.extname(asset.name) === '.js') {
+      suggestBundleSplitting = true;
+    }
+    console.log(
+      '  ' +
+        (isLarge ? chalk.yellow(sizeLabel) : sizeLabel) +
+        '  ' +
+        chalk.dim(asset.folder + path.sep) +
+        chalk.cyan(asset.name)
+    );
+  });
+  if (suggestBundleSplitting) {
+    console.log();
+    console.log(
+      chalk.yellow('The bundle size is significantly larger than recommended.')
+    );
+    console.log(
+      chalk.yellow(
+        'Consider reducing it with code splitting: https://goo.gl/9VhYWB'
+      )
+    );
+    console.log(
+      chalk.yellow(
+        'You can also analyze the project dependencies: https://goo.gl/LeUzfb'
+      )
+    );
+  }
+}
+
+function removeFileNameHash(buildFolder, fileName) {
+  return fileName
+    .replace(buildFolder, '')
+    .replace(
+      /\/?(.*)(\.[0-9a-f]+)(\.chunk)?(\.js|\.css)/,
+      (match, p1, p2, p3, p4) => p1 + p4
+    );
+}
+
+// Input: 1024, 2048
+// Output: "(+1 KB)"
+function getDifferenceLabel(currentSize, previousSize) {
+  var FIFTY_KILOBYTES = 1024 * 50;
+  var difference = currentSize - previousSize;
+  var fileSize = !Number.isNaN(difference) ? filesize(difference) : 0;
+  if (difference >= FIFTY_KILOBYTES) {
+    return chalk.red('+' + fileSize);
+  } else if (difference < FIFTY_KILOBYTES && difference > 0) {
+    return chalk.yellow('+' + fileSize);
+  } else if (difference < 0) {
+    return chalk.green(fileSize);
+  } else {
+    return '';
+  }
+}
+
+function measureFileSizesBeforeBuild(buildFolder) {
+  return new Promise(resolve => {
+    recursive(buildFolder, (err, fileNames) => {
+      var sizes;
+      if (!err && fileNames) {
+        sizes = fileNames
+          .filter(fileName => /\.(js|css)$/.test(fileName))
+          .reduce((memo, fileName) => {
+            var contents = fs.readFileSync(fileName);
+            var key = removeFileNameHash(buildFolder, fileName);
+            memo[key] = gzipSize(contents);
+            return memo;
+          }, {});
+      }
+      resolve({
+        root: buildFolder,
+        sizes: sizes || {},
+      });
+    });
+  });
+}
+
+module.exports = {
+  measureFileSizesBeforeBuild: measureFileSizesBeforeBuild,
+  printFileSizesAfterBuild: printFileSizesAfterBuild,
+};