Added setState documentation

README.md

@@ -23,6 +23,7 @@ A form input builder and validator for React JS
     - [onInvalid()](#oninvalid)
   - [Formsy.Mixin](#formsymixin)
     - [name](#name)
+    - [value](#value)
     - [validations](#validations)
     - [validationError](#validationerror)
     - [required](#required)
@@ -246,6 +247,12 @@ Whenever the form becomes invalid the "onInvalid" handler is called. Use it to f
 ```
 The name is required to register the form input component in the form.
 
+#### <a name="value">value</a>
+```html
+<MyInputComponent name="email" value="My default value"/>
+```
+You should always use the **getValue()** method inside your formsy form element. To pass a default value, use the value attribute.
+
 #### <a name="validations">validations</a>
 ```html
 <MyInputComponent name="email" validations="isEmail"/>

src/main.js

@@ -64,10 +64,15 @@ var request = function (method, url, data, contentType, headers) {
       xhr.onreadystatechange = function () {
         if (xhr.readyState === 4) {
 
-          if (xhr.status >= 200 && xhr.status < 300) {
-            resolve(xhr.responseText ? JSON.parse(xhr.responseText) : null);
-          } else {
-            reject(xhr.responseText ? JSON.parse(xhr.responseText) : null);
+          try {
+            var response = xhr.responseText ? JSON.parse(xhr.responseText) : null;
+            if (xhr.status >= 200 && xhr.status < 300) {
+              resolve(response);
+            } else {
+              reject(response);
+            }
+          } catch (e) {
+            reject(e);
           }
 
         }
@@ -221,7 +226,7 @@ Formsy.Form = React.createClass({
 
     this.props.onSubmit();
 
-    var headers = (Object.keys(this.props.headers).length && this.props.headers) || options.headers;
+    var headers = (Object.keys(this.props.headers).length && this.props.headers) || options.headers || {};
 
     ajax[this.props.method || 'post'](this.props.url, this.model, this.props.contentType || options.contentType || 'json', headers)
       .then(function (response) {