Refactor to use async/await

Author: calvinl

README.md

@@ -81,6 +81,10 @@ resolved.
 
 See the [TodosContainer](common/js/containers/Todos/index.js) for an example.
 
+## Async / Await
+This project uses `async/await`, available by default in Node.js v8.x.x or
+higher. If you experience errors, please upgrade your version of Node.js.
+
 ## Writing Tests
 The default testing framework is Mocha, though you can use whatever you want.
 Make sure you have it installed:

common/js/actions/todos.js

@@ -14,12 +14,15 @@ export const fetchTodosSuccess = generateActionCreator(FETCH_TODOS_SUCCESS, 'tod
 export const fetchTodosFailure = generateActionCreator(FETCH_TODOS_FAILURE, 'error');
 
 export const fetchTodos = () => {
-  return (dispatch) => {
+  return async (dispatch) => {
     dispatch(fetchTodosRequest());
 
-    return fetch('/api/todos', { method: 'GET' })
-      .then(res => res.json())
-      .then(todos => dispatch(fetchTodosSuccess(todos)))
-      .catch(error => dispatch(fetchTodosFailure(error)));
+    try {
+      const response = await fetch('/api/todos', { method: 'GET' });
+      const todos = await response.json();
+      dispatch(fetchTodosSuccess(todos));
+    } catch (e) {
+      dispatch(fetchTodosFailure(e.message));
+    }
   };
 };