Add compress-images action

package.json

@@ -1,13 +1,14 @@
 {
   "name": "medic-configurer-beta",
-  "version": "1.0.23",
+  "version": "1.0.24",
   "description": "Configure Medic Mobile deployments",
   "main": "index.js",
   "scripts": {
     "test": "grunt jshint test"
   },
   "bin": {
-    "medic-conf": "bin/medic-conf"
+    "medic-conf": "bin/medic-conf",
+    "medic-pngout": "bin/pngout"
   },
   "repository": {
     "type": "git",

src/cli/supported-actions.js

@@ -2,6 +2,7 @@ module.exports = [
   'backup-app-settings',
   'backup-forms',
   'compile-app-settings',
+  'compress-images',
   'convert-forms',
   'delete-forms',
   'upload-app-settings',

src/fn/compress-images.js

@@ -0,0 +1,22 @@
+const exec = require('../lib/exec-promise');
+const fs = require('../lib/sync-fs');
+const info = require('../lib/log').info;
+const trace = require('../lib/log').trace;
+
+module.exports = (project/*, couchUrl*/) => {
+  return fs.recurseFiles(project)
+    .filter(name => name.endsWith('.png'))
+    .map(f => { console.log('compressing png: ', f); return f; })
+    .reduce((promiseChain, png) =>
+      promiseChain
+        .then(() => info('Compressing PNG:', png, '…'))
+        .then(() =>
+            exec('pngout', `'${png}'`)
+              .then(() => trace('Compressed', png))
+              .catch(e => {
+                if(e.status === 2) {
+                  info('Unable to compress further.');
+                } else throw e;
+              })),
+      Promise.resolve());
+};

src/lib/exec-promise.js

@@ -1,7 +1,15 @@
-const exec = require('child_process').exec;
+const execSync = require('child_process').execSync;
 
-module.exports = (...args) =>
-  new Promise((resolve, reject) =>
-    exec(args.join(' '), err => {
-      return err ? reject(err) : resolve();
-    }));
+// TODO might be important to sanitise input to `exec()` to prevent injection
+// attacks by devious tech leads.
+
+module.exports = (...args) => {
+  try {
+    execSync(args.join(' '), {
+      stdio: ['ignore', process.stdout, process.stderr],
+    });
+    return Promise.resolve();
+  } catch(e) {
+    return Promise.reject(e);
+  }
+};

src/lib/sync-fs.js

@@ -1,4 +1,6 @@
 const fs = require('fs');
+const path = require('path');
+const trace = require('../lib/log').trace;
 const warn = require('../lib/log').warn;
 
 function read(path) {
@@ -19,6 +21,26 @@ function readJson(path) {
   }
 }
 
+function recurseFiles(dir, files) {
+  if(!files) files = [];
+
+  fs.readdirSync(dir)
+    .forEach(name => {
+      const f = path.join(dir, name);
+      try {
+        const stat = fs.statSync(f);
+
+        if(stat.isDirectory()) recurseFiles(f, files);
+        else files.push(f);
+      } catch(e) {
+        if(e.code === 'ENOENT') trace('Ignoring file (err ENOENT - may be a symlink):', f);
+        else throw e;
+      }
+    });
+
+  return files;
+}
+
 function withoutExtension(fileName) {
   const extensionStart = fileName.lastIndexOf('.');
   return extensionStart === -1 ? fileName : fileName.substring(0, extensionStart);
@@ -30,6 +52,7 @@ module.exports = {
   read: read,
   readJson: readJson,
   readBinary: path => fs.readFileSync(path),
+  recurseFiles: recurseFiles,
   readdir: fs.readdirSync,
   withoutExtension: withoutExtension,
   write: (path, content) => fs.writeFileSync(path, content, 'utf8'),