Improving customization

README.md

@@ -43,6 +43,12 @@ model.save();
 
 This will send the ``attachment`` and all other attributes as a FormData object.
 
+## Customization
+
+You can override `getFormFields()` to select the fields you want to transform into FormData. The method is passed the model snapshot as unique parameter. If you want to customize the name for the key, overrides `getFormKey()` which is passed with the `key` and `value` for that key of the hash returned by `getFormFields()`. To customize the value, use `getFormValue()`.
+
+Do not abuse these customization. If you're performing huge changes in your model's representation, then you should be providing a custom serializer or maybe a different transformation for an specific field.
+
 ### Thanks
 
-This addon was inspired by Matt Beedle's blog post http://blog.mattbeedle.name/posts/file-uploads-in-ember-data/
+This addon was inspired by Matt Beedle's blog post http://blog.mattbeedle.name/posts/file-uploads-in-ember-data/

addon/mixins/form-data-adapter.js

@@ -13,13 +13,16 @@ export default Ember.Mixin.create({
 
     if (typeof FormData !== 'undefined' && data && this.formDataTypes.contains(type)) {
       var formData = new FormData();
-      var root = Ember.keys(data)[0];
-
-      Ember.keys(data[root]).forEach(function(key) {
-        if (typeof data[root][key] !== 'undefined') {
-          formData.append(root + "[" + key + "]", data[root][key]);
+      var fields = this.getFormFields(data);
+
+      Ember.keys(fields).forEach(function(key) {
+        if (typeof fields[key] !== 'undefined') {
+          formData.append(
+            this.getFormKey(key, fields[key]),
+            this.getFormValue(key, fields[key])
+          );
         }
-      });
+      }.bind(this));
 
       hash.processData = false;
       hash.contentType = false;
@@ -28,4 +31,17 @@ export default Ember.Mixin.create({
 
     return hash;
   },
+
+  getFormFields: function (data) {
+    this._root = this._root || Ember.keys(data)[0];
+    return data[this._root];
+  },
+
+  getFormKey: function (key, value) {
+    return this._root + "[" + key + "]";
+  },
+
+  getFormValue: function (key, value) {
+    return value;
+  }
 });