Add support to dynamic exported filename

.gitignore

@@ -1,5 +1,6 @@
 node_modules
 bower_components
 dist
+*.log
 
 .idea

bower.json

@@ -1,6 +1,6 @@
 {
   "name": "ng-csv",
-  "version": "0.3.6",
+  "version": "0.3.7",
   "main": "build/ng-csv.min.js",
   "dependencies": {
     "angular": "~1",

build/ng-csv.js

@@ -135,8 +135,11 @@ angular.module('ngCsv.services').
             var labelArray, labelString;
 
             labelArray = [];
-            angular.forEach(arrData[0], function(value, label) {
-                this.push(that.stringifyField(label, options));
+
+            var iterator = !!options.columnOrder ? options.columnOrder : arrData[0];
+            angular.forEach(iterator, function(value, label) {
+                var val = !!options.columnOrder ? value : label;
+                this.push(that.stringifyField(val, options));
             }, labelArray);
             labelString = labelArray.join(options.fieldSep ? options.fieldSep : ",");
             csvContent += labelString + EOL;
@@ -210,7 +213,7 @@ angular.module('ngCsv.directives').
       restrict: 'AC',
       scope: {
         data: '&ngCsv',
-        filename: '@filename',
+        filename: '&filename',
         header: '&csvHeader',
         columnOrder: '&csvColumnOrder',
         txtDelim: '@textDelimiter',
@@ -240,7 +243,13 @@ angular.module('ngCsv.directives').
           }
 
           $scope.getFilename = function () {
-            return $scope.filename || 'download.csv';
+            var filename = 'download.csv';
+            if(angular.isFunction($scope.filename)){
+              filename = $scope.filename() || filename;
+            }else{
+              filename = $scope.filename||filename;
+            }
+            return filename;
           };
 
           function getBuildCsvOptions() {
@@ -268,10 +277,16 @@ angular.module('ngCsv.directives').
            */
           $scope.buildCSV = function () {
             var deferred = $q.defer();
+            var data = null;
 
             $element.addClass($attrs.ngCsvLoadingClass || 'ng-csv-loading');
 
-            CSV.stringify($scope.data(), getBuildCsvOptions()).then(function (csv) {
+            data = $scope.data();
+            if(angular.isFunction(data)){
+              data = data();
+            }
+
+            CSV.stringify(data, getBuildCsvOptions()).then(function (csv) {
               $scope.csv = csv;
               $element.removeClass($attrs.ngCsvLoadingClass || 'ng-csv-loading');
               deferred.resolve(csv);