Tag: Java

As part of some work I have been undertaking to integrate the UK Government Notifications service into Mendix, I needed to be able to make API calls from behind a firewall using a proxy in a Java action.

Due to the lower level Java actions in Mendix run at, proxy settings are not automatically applied, and must be added manually. I wanted to explain how to get the proxy settings from Mendix, and use them a Java action.

I’ve previously explained how to add proxy settings to Mendix, so I assume this step has been completed.

In a Java action, we need to get these from the HttpConfiguration singleton.

import com.mendix.http.HttpConfiguration;
import com.mendix.http.IHttpConfiguration;
import com.mendix.http.IProxyConfiguration;

IHttpConfiguration httpconf = com.mendix.http.HttpConfiguration.getInstance();
IProxyConfiguration proxyconf = httpconf.getProxyConfiguration().orElse(null);

We can now check if we have a proxy configuration set, if we don’t proxyconf will be null.

The username and password for the proxy can be retrieved using the getUser() and getPassword() methods.

String username = proxyconf.getUser().orElse(null);
String password = proxyconf.getPassword().orElse(null);

If they are present we can build a Java Authenticator object and set it as the default authenticator.

import java.net.Authenticator;
import java.net.PasswordAuthentication;

if (username != null && password != null) {
    Authenticator authenticator = new Authenticator() {
        public PasswordAuthentication getPasswordAuthentication() {
           return (new PasswordAuthentication(username, password.toCharArray()));
        }
    };

    Authenticator.setDefault(authenticator);
}

Next we need to create the Proxy object. We need to get the host and port of our proxy server from Mendix using the getHost() and getPort() methods.

import java.net.InetSocketAddress;
import java.net.Proxy;

InetSocketAddress proxyLocation = new InetSocketAddress(proxyconf.getHost(), proxyconf.getPort());
Proxy proxy = new Proxy(Proxy.Type.HTTP, proxyLocation);

The proxy can be used for Java network actions.

An example of using this would be the UK Government Notifications client. It has a second optional paramater in it’s constructor for a Proxy.

client = new NotificationClient('APIKey', proxy);