WorkerExtensionStartupAttribute does not work for F#

[jviau]

Issue

Types marked with WorkerExtensionStartupAttribute are not being called automatically on worker startup when using F#. This is due to this attribute relying on ExtensionStartupRunnerGenerator (source gen) to function - which does not work for F#.

Impact

Any extension which relies on that attribute to configure themselves does not work for F#. One such extension is Durable Functions, which uses that attribute to inject services and configure options.

Workaround

In environments where source generation does not run, applications will need to manually configure extensions on startup:

Host.CreateDefaultBuilder()
    .ConfigureFunctionsWorkerDefaults(app =>
    {
        new ServiceBusExtensionStartup().Configure(app);
    });

[kmadof]

Any update here?

[jviau]

@kmadof the workaround is to manually configure the extension. The root issue is external to us: source generation is not available in F#.

[kmadof]

I found the issue (Support Source Generators #864) confirming your words