extensionBundle in host.json breaks DI

[bcraun]

I have an issue I finally traced to the extensionBundle changes in host.json which are causing DI to not work in a queue-triggered function. I am using IFunctionsHostBuilder and it works correctly if the extensions are omitted.

DI works:

{
    "version": "2.0"
}

DI doesn't work:

{
    "version": "2.0",
    "extensionBundle": {
        "id": "Microsoft.Azure.Functions.ExtensionBundle",
        "version": "[1.*, 2.0.0)"
    }
}

My queue-triggered function still works without the extensionBundle specified and I would like to understand under what scenarios are they needed?

Thanks

[jeffhollan]

If using Dependency Injection (or .net code in general) you do not need and should not use extension bundles. Extension bundles are for bundling in extensions (which in .net you pull in as NuGet packages) to the app