Add support for Azure Functions in Aspire

[vl4d4]

This work item tracks the work to support integrating .NET Azure Functions projects to the Aspire app model, support local development with debugging in VS and VS Code, and support deploying Azure Functions to ACA.

This only applies to the new v4 isolated workers and will not work for in process functions.

Local Development Experience

• Ability to reference a .NET Azure Functions project in the app model as a project resource
• [ ] Ability to reference a non-.NET azure functions project in the app model (not target for 9.0 GA)
• Ability to reference cloud resources and have them be picked up by functions (service bus, blobs etc)
• Ability to use service discovery in a Functions worker app
• Ability to consume telemetry emitted from Azure Functions host from Aspire dashboard (For .NET 8 Azure Function templates)
• Ability to debug Azure Functions projects in Aspire (Visual Studio)
• Ability to debug Azure Functions projects in Aspire (VS Code)

Deployment

• Ability to deploy an Azure Functions app in Aspire to ACA (targeted for 9.0 GA)
• Ability to deploy an Azure Functions app in Aspire to Azure Functions (not targeted for 9.0 GA)

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Original

Do you plan to integrate Aspire with Azure functions (I haven’t seen similar question in dotnet Conf nor samples and docs)?

[davidfowl]

Yes we plan to support functions as well, but it's not yet supported in the first preview.

cc @fabiocav

[alefranz]

what's missing to support Aspire in Azure Functions v4 isolated?
Would be nice to sketch out the required elements and identify which one are up for grabs, so we as a community can help. Thanks!

[flibbertigibbet-uk]

If the Aspire cloud deployment manifest tooling could automate the hosting & config of Azure Functions within Azure Container Apps (ACA) that would be fabulous. I need this but the protracted Dev/Ops guidance docs that describe how to host Azure functions within ACA have deterred me so far.

[davidfowl]

I added more details.

[fabiocav]

Also opened an issue and a new milestone in the .NET Worker repo to track the work happening there: Azure/azure-functions-dotnet-worker#2090

[josephaw1022]

I'm currently in the process of developing several local examples using Azure Functions with Aspire to better understand their capabilities and limitations. During this spike, I've encountered several issues and have a few questions. Could you please advise on the appropriate repository and process for reporting these issues and inquiries related to Azure Functions specifically with Aspire?

[josephaw1022]

✅ - Ability to reference a .NET azure functions project in the app model
✅ - Ability to use service discovery in a function

I am able to spin it up locally, but am having trouble with getting rabbitmq consumer attribute parameter to work properly

And in the logs of the consumer I am seeing some connection issues, which I assume is just the function trying to connect to the container before it's actually up and running

link to repo: https://github.com/josephaw1022/AspireWithAzureFunctions

[sjasperse]

I have been trying to get something working locally also, and you are further than I am - but don't you need the ServiceDefaults added?

Without it, wouldn't it just be using your local.settings.json?

Edit: I just remembered. I had to modify the ServiceDefaults extensions to be able to apply it to the function app host builder. Here are my changes if it helps you at all:
https://gist.github.com/sjasperse/2008cfcc4acee3ceeea7033a0e56af65

Site note: How is yours running? When I pull your repo and run it, my function app says "The gRPC channel URI 'http://:'/; could not be parsed." which is all the further I've gotten in my own experimenting also.

[josephaw1022]

• This is good stuff! I was trying to figure out how exactly how do this and stuck on that piece with the service defaults. I can add that to my repo. I'm just doing it in my repo right now and then going to put a pr into the samples repo once I have something presentable lol. Just having issues with the sln building (and something with the csproj and needing to make a build.prop.targets) and just want to stay focused on getting the poc done first. But anyway, I am not sure what the issue is and why anything grpc is being mentioned? Can you send a screenshot of the terminal with the error? I am just running this via visual studio 2022 preview with the .net 8 and all that. And the service defaults method is just the method that you made. All it does is the metrics and services. It doesn't really have anything to do with configuration values.

[sjasperse]

I put my code in a repo for you. Basically just the Aspire Starter template, plus a templated function app (manually set to .NET 8).
Here is a repo: https://github.com/sjasperse/AspireStarterWithFunctions/tree/master/AspireStarter.AppFunctions

Screenshot of the terminal output:

From what I can google, this sounds like an expected error when the function app is started like a regular .exe project, instead of using func start (which makes sense that it would expect the function runtime to be there) - so I'm confused how you have it working :-). I didn't really expect it to work, until I saw your screenshot and I started scratching my head.

Also - I'm on a Mac. Maybe that has something to do with it?

[josephaw1022]

I put my code in a repo for you. Basically just the Aspire Starter template, plus a templated function app (manually set to .NET 8). Here is a repo: https://github.com/sjasperse/AspireStarterWithFunctions/tree/master/AspireStarter.AppFunctions

Screenshot of the terminal output:

From what I can google, this sounds like an expected error when the function app is started like a regular .exe project, instead of using func start (which makes sense that it would expect the function runtime to be there) - so I'm confused how you have it working :-). I didn't really expect it to work, until I saw your screenshot and I started scratching my head.

Also - I'm on a Mac. Maybe that has something to do with it?

I would remove the

 tracing.AddAspNetCoreInstrumentation()
     .AddGrpcClientInstrumentation()
     .AddHttpClientInstrumentation();

from the extension method in service defaults.

Not an actual fix to the core issue, but might or might not fix the issue from occuring