Implemented tracking of changes to s3 assets

Gruntfile.js

@@ -17,7 +17,8 @@ module.exports = function (grunt) {
         port: 1337,
         secure: false,
         access: 'public-read',
-        style: 'path'
+        style: 'path',
+        trackChanges: true
       },
       test: {
         options: {}

README.md

@@ -60,6 +60,7 @@ and a `dest`. Any of the above values may also be overriden.
 * **del** - (*array*) An array of objects, each object containing a `src` to delete from s3. Any of
 the above values may also be overriden.
 * **sync** - (*array*) An array of ojects, each oject containing a `src` and `dest`. Default behavior is to only upload new files (that don't exist). Set a key called `verify` with the value `true` on this object's options property (i.e. `options: {verify: true}`) to upload existing files if and only if they are newer than the versions of those same files on the server. This is implemented via an MD5 hash and by checking the modified times of the files.
+* **trackChanges** - (*boolean*) Default `false`. If true, an array of changed assets can be retrieved from `grunt.config('s3.changed')`
 * **debug** - (*boolean*) If true, no transfers with S3 will occur, will print all actions for review by user
 * **logSuccess** - (*boolean*) If false, output for successful transfers will be ignored. Default: true
 * **logErrors** - (*boolean*) If false, output for failed transfers will be ignored. Default: true

tasks/lib/s3.js

@@ -79,7 +79,7 @@ exports.init = function (grunt) {
   /**
    * Create an s3 client. Returns an Knox instance.
    *
-   * @param {Object} Format.
+   * @param {Object} options.
    * @returns {Object}
    */
   var makeClient = exports.makeClient = function(options) {
@@ -88,6 +88,20 @@ exports.init = function (grunt) {
     ]));
   };
 
+  /**
+   * Track a change to an asset on s3
+   *
+   * @param {String} path of changed asset.
+   * @returns {Object}
+   */
+  var trackChanges = function(path) {
+    var changes = grunt.config.get('s3.changed') || [];
+    if (changes.indexOf(path) < 0 ) {
+      changes.push(path);
+    }
+    grunt.config.set('s3.changed', changes);
+  };
+
   /**
    * Publishes the local file at src to the s3 dest.
    *
@@ -151,6 +165,9 @@ exports.init = function (grunt) {
 
               if (remoteHash === localHash) {
                 var msg = util.format(MSG_UPLOAD_SUCCESS, prettySrc, client.bucket, dest, localHash);
+                if (options.trackChanges) {
+                  trackChanges(dest);
+                }
                 cb(null, msg);
               }
               else {
@@ -364,6 +381,9 @@ exports.init = function (grunt) {
         dfd.reject(makeError(MSG_ERR_DELETE, src, err || res.statusCode));
       }
       else {
+        if (options.trackChanges) {
+          trackChanges(src);
+        }
         dfd.resolve(util.format(MSG_DELETE_SUCCESS, src));
       }
     });

test/common.js

@@ -11,5 +11,17 @@ var common = module.exports = {
 
   clean: function(cb) {
     rimraf(__dirname + '/../s3', cb);
+  },
+
+  setup: function(cb) {
+    grunt.config.set('s3.changed', []);
+    common.clean(cb);
+  },
+
+  upload: function(file) {
+    return function(cb) {
+      s3.upload(__dirname + '/files/a.txt', 'a.txt', common.config).done(cb);
+    }
   }
-}
+}
+

test/delete.js

@@ -13,17 +13,15 @@ var hashFile = require('../tasks/lib/common').hashFile
 module.exports = {
   setUp: function(cb) {
     async.series([
-      common.clean,
-      function(done) {
-        s3.upload(__dirname + '/files/a.txt', 'a.txt', common.config).done(done);
-      }
+      common.setup,
+      common.upload('a.txt')
     ], function() {
       cb();
     });
   },
 
   testDelete: function(test) {
-    test.expect(4);
+    test.expect(5);
 
     var dest = 'a.txt';
     var client = s3.makeClient(config);
@@ -45,6 +43,7 @@ module.exports = {
         client.getFile(dest, function (err, res) {
           test.ifError(err);
           test.equal(res.statusCode, 404, 'File does not exist.');
+          test.deepEqual(grunt.config('s3.changed'), ['a.txt']);
           next();
         }, 500);
       }

test/download.js

@@ -13,10 +13,8 @@ var s3Config = grunt.config("s3")
 module.exports = {
   setUp: function(cb) {
     async.series([
-      common.clean,
-      function(done) {
-        s3.upload(__dirname + '/files/a.txt', 'a.txt', common.config).done(done);
-      }
+      common.setup,
+      common.upload('a.txt')
     ], function() {
       cb();
     });

test/s3Task.js

@@ -36,7 +36,7 @@ var makeMockTask = function (taskDef) {
 };
 
 module.exports = {
-  setUp: common.clean,
+  setUp: common.setup,
   run: function (test) {
     var taskDef = new _.Deferred();
     var asyncCalls = 0;

test/sync.js

@@ -12,7 +12,7 @@ var s3Config = grunt.config("s3")
   , config = common.config;
 
 module.exports = {
-  setUp: common.clean,
+  setUp: common.setup,
 
   testSync: function (test) {
     test.expect(1);

test/upload.js

@@ -12,10 +12,10 @@ var s3Config = grunt.config("s3")
   , config = common.config;
 
 module.exports = {
-  setUp: common.clean,
+  setUp: common.setup,
 
   testUpload : function (test) {
-    test.expect(2);
+    test.expect(3);
 
     async.series([
       function (cb) {
@@ -25,6 +25,7 @@ module.exports = {
         s3.upload(src, 'a.txt', config)
           .done(function () {
             test.ok(hashFile(src) === hashFile(dest), 'File uploaded successfully.');
+            test.deepEqual(grunt.config('s3.changed'), ['a.txt']);
           })
           .always(function () {
             cb(null);