io.netty.example.http.cors

Class HttpCorsServer

java.lang.Object

io.netty.example.http.cors.HttpCorsServer

public final class HttpCorsServer
extends Object

This example server aims to demonstrate Cross Origin Resource Sharing (CORS) in Netty. It does not have a client like most of the other examples, but instead has a html page that is loaded to try out CORS support in a web brower.

CORS is configured in HttpCorsServerInitializer and by updating the config you can try out various combinations, like using a specific origin instead of a wildcard origin ('*').

The file src/main/resources/cors/cors.html contains a very basic example client which can be used to try out different configurations. For example, you can add custom headers to force a CORS preflight request to make the request fail. Then to enable a successful request, configure the CorsHandler to allow that/those request headers.

Testing CORS

You can either load the file src/main/resources/cors/cors.html using a web server or load it from the file system using a web browser.

Using a web server

To test CORS support you can serve the file src/main/resources/cors/cors.html using a web server. You can then add a new host name to your systems hosts file, for example if you are on Linux you may update /etc/hosts to add an addtional name for you local system:

 127.0.0.1   localhost domain1.com
 

Now, you should be able to access http://domain1.com/cors.html depending on how you have configured you local web server the exact url may differ.

Using a web browser

Open the file src/main/resources/cors/cors.html in a web browser. You should see loaded page and in the text area the following message:

 'CORS is not working'
 

If you inspect the headers being sent using your browser you'll see that the 'Origin' request header is 'null'. This is expected and happens when you load a file from the local file system. Netty can handle this by configuring the CorsHandler which is done in the HttpCorsServerInitializer.

Constructor Summary

Constructors

Constructor and Description
HttpCorsServer()

Method Summary

Methods

Modifier and Type	Method and Description
static void	main(String[] args)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

HttpCorsServer

public HttpCorsServer()

Method Detail

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception