An application can implement a controller to handle HTTP requests. This is done by adding a main.js JavaScript file at the root of the application (/src/main/resources/).
The HTTP requests are handled independent of any site or content, on a specific URL with the path /app/[app-id] (e.g. "/app/com.enonic.app.superhero").
The main.js file acts as any other controller and may expose a function for each HTTP method that should be handled: GET, POST, etc. Or an all function to handle requests with any method. (see http_controllers).
The function that handles the request receives the request object as a parameter and returns the response object .
The following is an example of an application controller, in main.js.
code/main-controller.js
The asset files of an application (see assets) are also available under the application controller URL.
For example, the asset in src/main/resources/assets/css/styles.css in application with name com.enonic.myapp can be requested with the URL /app/com.enonic.myapp/css/styles.css.