Cache images

Closes #40
gruntjs · Aug 11, 2013 · f30029b · f30029b
1 parent a310571
commit f30029b
Show file tree

Hide file tree

Showing 4 changed files with 64 additions and 3 deletions.
diff --git a/.gitignore b/.gitignore
@@ -1,3 +1,4 @@
 node_modules
 npm-debug.log
 tmp
+tmp-cache/
diff --git a/Gruntfile.js b/Gruntfile.js
@@ -34,7 +34,7 @@ module.exports = function (grunt) {
       }
     },
     nodeunit: {
-      tasks: ['test/*_test.js']
+      tests: ['test/*_test.js']
     }
   });
 

diff --git a/tasks/imagemin.js b/tasks/imagemin.js
@@ -15,6 +15,23 @@ module.exports = function (grunt) {
     var filesize = require('filesize');
     var optipngPath = require('optipng-bin').path;
     var jpegtranPath = require('jpegtran-bin').path;
+    var crypto = require('crypto');
+    var os = require('os');
+
+    var cacheDirectory = (os.tmpdir || function() {
+        if (process.platform === 'win32') {
+            return process.env.TEMP || process.env.TMP || (process.env.SystemRoot || process.env.windir) + '\\temp';
+        } else {
+            return process.env.TMPDIR || process.env.TMP || process.env.TEMP || '/tmp';
+        }
+    })();
+    cacheDirectory = path.join(cacheDirectory, 'grunt-contrib-imagemin.cache');
+
+    function hashFile(filePath) {
+        var content = grunt.file.read(filePath);
+
+        return crypto.createHash('sha1').update(content).digest('hex');
+    }
 
     grunt.registerMultiTask('imagemin', 'Minify PNG and JPEG images', function () {
         var done = this.async();
@@ -49,6 +66,7 @@ module.exports = function (grunt) {
         function optimize(src, dest, next) {
             var cp;
             var originalSize = fs.statSync(src).size;
+            var cachePath = path.join(cacheDirectory, hashFile(src));
 
             function processed(err, result, code) {
                 var saved, savedMsg;
@@ -60,19 +78,33 @@ module.exports = function (grunt) {
                 saved = originalSize - fs.statSync(dest).size;
                 totalSaved += saved;
 
-                if (result.stderr.indexOf('already optimized') !== -1 || saved < 10) {
+                if (result && (result.stderr.indexOf('already optimized') !== -1 || saved < 10)) {
                     savedMsg = 'already optimized';
                 } else {
                     savedMsg = 'saved ' + filesize(saved);
                 }
 
+                if (!grunt.file.exists(cachePath)) {
+                    grunt.file.copy(dest, cachePath);
+
+                    if (grunt.option('verbose')) {
+                        grunt.log.writeln('[Caching] ' + cachePath + ' <- ' + src);
+                    }
+                }
+
                 grunt.log.writeln('✔ '.green + src + (' (' + savedMsg + ')').grey);
                 next();
             }
 
             grunt.file.mkdir(path.dirname(dest));
 
-            if (path.extname(src).toLowerCase() === '.png') {
+            if (grunt.file.exists(cachePath)) {
+                if (grunt.option('verbose')) {
+                    grunt.log.writeln('[Cached] ' + cachePath + ' -> ' + src);
+                }
+                grunt.file.copy(cachePath, dest);
+                processed();
+            } else if (path.extname(src).toLowerCase() === '.png') {
                 // OptiPNG can't overwrite without creating a backup file
                 // https://sourceforge.net/tracker/?func=detail&aid=3607244&group_id=151404&atid=780913
                 if (dest !== src && grunt.file.exists(dest)) {

diff --git a/test/imagemin_test.js b/test/imagemin_test.js
@@ -1,6 +1,18 @@
 'use strict';
 var grunt = require('grunt');
 var fs = require('fs');
+var path = require('path');
+var crypto = require('crypto');
+var os = require('os');
+
+var cacheDirectory = (os.tmpdir || function() {
+    if (process.platform === 'win32') {
+        return process.env.TEMP || process.env.TMP || (process.env.SystemRoot || process.env.windir) + '\\temp';
+    } else {
+        return process.env.TMPDIR || process.env.TMP || process.env.TEMP || '/tmp';
+    }
+})();
+cacheDirectory = path.join(cacheDirectory, 'grunt-contrib-imagemin.cache');
 
 exports.imagemin = {
     minifyPng: function (test) {
@@ -21,6 +33,14 @@ exports.imagemin = {
 
         test.done();
     },
+    cachePng: function (test) {
+        test.expect(1);
+
+        var original = crypto.createHash('sha1').update(grunt.file.read('test/fixtures/test.png')).digest('hex');
+        test.ok(fs.existsSync(path.join(cacheDirectory, original)), 'should cached PNG images');
+
+        test.done();
+    },
     minifyJpg: function (test) {
         test.expect(1);
 
@@ -37,6 +57,14 @@ exports.imagemin = {
         var original = fs.statSync('test/fixtures/test-uppercase.JPG').size;
         test.ok(actual < original, 'should minify uppercase extension JPG images');
 
+        test.done();
+    },
+    cacheJpg: function (test) {
+        test.expect(1);
+
+        var original = crypto.createHash('sha1').update(grunt.file.read('test/fixtures/test.jpg')).digest('hex');
+        test.ok(fs.existsSync(path.join(cacheDirectory, original)), 'should cached JPG images');
+
         test.done();
     }
 };