Remote WebDriver server

The server will always run on the machine with the browser you want to test. The server can be used either from the command line or through code configuration.

Starting the server from the command line

Once you have downloaded selenium-server-standalone-{VERSION}.jar, place it on the computer with the browser you want to test. Then, from the directory with the jar, run the following:

java -jar selenium-server-standalone-{VERSION}.jar

Considerations for running the server

The caller is expected to terminate each session properly, calling either Selenium#stop() or WebDriver#quit.

The selenium-server keeps in-memory logs for each ongoing session, which are cleared when Selenium#stop() or WebDriver#quit is called. If you forget to terminate these sessions, your server may leak memory. If you keep extremely long-running sessions, you will probably need to stop/quit every now and then (or increase memory with -Xmx jvm option).

Timeouts (from version 2.21)

The server has two different timeouts, which can be set as follows:

java -jar selenium-server-standalone-{VERSION}.jar -timeout=20 -browserTimeout=60
  • browserTimeout
    • Controls how long the browser is allowed to hang (value in seconds).
  • timeout
    • Controls how long the client is allowed to be gone before the session is reclaimed (value in seconds).

The system property selenium.server.session.timeout is no longer supported as of 2.21.

Please note that the browserTimeout is intended as a backup timeout mechanism when the ordinary timeout mechanism fails, which should be used mostly in grid/server environments to ensure that crashed/lost processes do not stay around for too long, polluting the runtime environment.

Configuring the server programmatically

In theory, the process is as simple as mapping the DriverServlet to a URL, but it is also possible to host the page in a lightweight container, such as Jetty, configured entirely in code.

  • Download the selenium-server.zip and unpack.
  • Put the JARs on the CLASSPATH.
  • Create a new class called AppServer. Here, we are using Jetty, so you will need to download that as well:

    import org.mortbay.jetty.Connector;
    import org.mortbay.jetty.Server;
    import org.mortbay.jetty.nio.SelectChannelConnector;
    import org.mortbay.jetty.security.SslSocketConnector;
    import org.mortbay.jetty.webapp.WebAppContext;
    
    import javax.servlet.Servlet;
    import java.io.File;
    
    import org.openqa.selenium.remote.server.DriverServlet;
    
    public class AppServer {
    private Server server = new Server();
    
    public AppServer() throws Exception {
    WebAppContext context = new WebAppContext();
    context.setContextPath("");
    context.setWar(new File("."));
    server.addHandler(context);
    
    context.addServlet(DriverServlet.class, "/wd/*");
    
    SelectChannelConnector connector = new SelectChannelConnector();
    connector.setPort(3001);
    server.addConnector(connector);
    
    server.start();
    }
    }