Publish Azure Function as NuGet package (or load function from external assembly)

Question

I'm looking into publishing a reusable Azure Function as a NuGet package, in order to easily consume it in other projects. This way I can reference the NuGet package in other projects. This way I could dynamically compose a set of Azure Functions to be deployed to an Azure Function service.

Is this currently possible? Or, can functions eg be defined in an external assembly, and be "picked up" by the Azure Function host?

I know this is possible with Azure WebJobs, but I haven't found a way to achieve the same result using Azure Functions.

Answer 1

Adding <FunctionsInDependencies>true</FunctionsInDependencies> in the .csproj file seems to do the trick.

Do make sure you actually call the dependency somewhere in the code (eg in Startup.cs ) to make sure the assembly isn't optimized away by the compiler.

Answer 2

Azure function host discovers function entry points in the same assembly of host (annotated by FunctionName in Run method). So you will only be able to externalize all the reusable codes to separate nugets, but would still need to define entry point for each of the function in the host. The function body might then be just bare minimum wrapper calling your reusable assets, but needs to be present in host. Would you mind to share a bit more about the scenario you are trying to solve?

EDIT: Thanks @Nsevens for trying this out. <FunctionsInDependencies>true</FunctionsInDependencies> in the.csproj would load functions from dependencies. There should be an explicit call of some method (may be just a noop one) of the dependency from the host to make it a hard dependency for the compiler. I did not see any official documentation about this.