Custom logging in Jetty 12 beta2 can fail due to NullPointerException in org.eclipse.jetty.server.Request

[minduch]

Jetty version
Jetty 12 beta2 - Embedded

Java version/vendor (use: java -version)
openjdk version "17.0.7" 2023-04-18
OpenJDK Runtime Environment Temurin-17.0.7+7 (build 17.0.7+7)
OpenJDK 64-Bit Server VM Temurin-17.0.7+7 (build 17.0.7+7, mixed mode, sharing)

OS type/version
Windows 11 - Microsoft Windows [Version 10.0.22631.1906]

Description
In case of errors in the code of the Jetty 12 emebbor, the custom log attempts to write out the request, but will fail due to NullPointerException's. Of course, Jetty is not to blame for the implementors problematic code, but this is nicely handled by try-catches and console logging, except if you add a custom logger to the server.

I have seens various such errors, and most of them are located in the org.eclipse.jetty.server.Request class such as get methods returning a String. For example:

    static String getRemoteAddr(Request request)
    {
        if (request == null)
            return null;
        SocketAddress remote = request.getConnectionMetaData().getRemoteSocketAddress();
        if (remote instanceof InetSocketAddress inetSocketAddress)
        {
            if (inetSocketAddress.isUnresolved())
                return inetSocketAddress.getHostString();

            InetAddress address = inetSocketAddress.getAddress();
            String result = address == null
                ? inetSocketAddress.getHostString()
                : address.getHostAddress();
            return HostPort.normalizeHost(result);
        }
        return remote.toString();
    }

could go NullPointerException at the last line. Perhaps this should be rewritten to something like:

        return (remote != null)? remote.toString(): "null" /* or something else? */;

This applies to some potential methods in the Request class, from what I have seen until now:

• getLocalAddr
• getRemoteAddr
• getServerName

In contrast, you have methods such as getRemotePort not having this problem as it doesn't attempt to use the remotevariable for method calls in its class:

    static int getRemotePort(Request request)
    {
        if (request == null)
            return -1;
        SocketAddress remote = request.getConnectionMetaData().getRemoteSocketAddress();
        if (remote instanceof InetSocketAddress)
            return ((InetSocketAddress)remote).getPort();
        return -1;
    }

Above you see the return -1; call not attempting to use remote that could potentially be null.

How to reproduce?
Having an embedded Jetty with a custom logger and causing exceptions in the embeddors code that are then caught by Jetty handlers.

The one that really came up to be the most troublesome was getRemoteAddr.

[joakime]

PR #9971 opened for this issue

[gregw]

finally done.... after locale excursion!