Add compress script to apply gzip to assets not packed by webpack

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All notable changes to the Zlux App Manager will be documented in this file.
 
+## `3.2.0`
+
+- Enhacement: Zowe v3 Desktop assets are now compressed so that the Desktop can load faster on slow internet. (#658)
+
 ## `3.0.0`
 
 - Enhancement: Updated the Desktop Angular version from 12 to 18. This makes V2 Angular apps incompatible with V3. Iframe and React is unaffected.

virtual-desktop/gzip.mjs

@@ -0,0 +1,49 @@
+/*
+  This program and the accompanying materials are
+  made available under the terms of the Eclipse Public License v2.0 which accompanies
+  this distribution, and is available at https://www.eclipse.org/legal/epl-v20.html
+
+  SPDX-License-Identifier: EPL-2.0
+
+  Copyright Contributors to the Zowe Project.
+*/
+
+import * as fs from 'node:fs';
+import * as path from 'node:path';
+import { execSync } from 'node:child_process';
+
+const GZIP_SIZE_MIN = 50000; //50 KB
+const GZIP_ATTEMPT_MAX = 1000000000; //1 GB. Don't try compressing large files, these likely are incompressible binary.
+const KEEP_RATIO = 0.85; // Items not compressed below this will not be kept as compressed
+
+function recurse(directory) {
+  const listing = fs.readdirSync(directory, {withFileTypes: true});
+  listing.forEach((dirent)=> {
+    let itemPath = path.join(directory, dirent.name);
+    if (dirent.isDirectory()) {
+      recurse(itemPath);
+    } else {
+      let stat = fs.statSync(itemPath);
+      if ((stat.size >= GZIP_SIZE_MIN) && (stat.size <= GZIP_ATTEMPT_MAX)) {
+        execSync('gzip -k '+dirent.name, {cwd: directory});
+        let itemPathGz = path.join(directory, dirent.name+'.gz');
+        let statGz = fs.statSync(itemPathGz);
+        //keep only one file: compressed file is kept if meaningfully smaller.
+        if ((stat.size*KEEP_RATIO) < statGz.size) {
+          fs.unlinkSync(itemPathGz);
+        } else {
+          fs.unlinkSync(itemPath);
+        }
+      }
+    }
+  });
+}
+
+try {
+  const listing = fs.readdirSync('web');  
+} catch (e) {
+  console.log('Could not read web directory, run build first.');
+  process.exit(1);
+}
+
+recurse('web');

virtual-desktop/package.json

@@ -10,6 +10,7 @@
     "start": "ng build --watch",
     "build": "ng build && npm run copy",
     "build:externals": "exit 0",
+    "compress": "node gzip.mjs",
     "copy": "cpx node_modules/requirejs/require.js web/",
     "i18n": "ng-xi18n -p tsconfig.ngx-i18n.json --i18nFormat=xlf  --outFile=messages.xlf && xliffmerge -p xliffmerge.json",
     "lint": "tslint -c tslint.json \"src/**/*.ts\""