Original issue: https://github.com/Azure/azure-webjobs-sdk/issues/2993

Issue description

The host extension Microsoft.Azure.WebJobs.Extensions.SignalRService 1.10.0 (corresponding to the worker extensions Microsoft.Azure.Functions.Worker.Extensions.SignalRService 1.10.0) has dependency resolution error on .NET 7 isolated worker runtime.

Error message:

Microsoft.Azure.WebJobs.Host: Error indexing method ‘Functions.OnConnected’. Microsoft.Azure.SignalR.Management: Could not load file or assembly ‘Microsoft.Extensions.Options, Version=7.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60’. The system cannot find the file specified.

Comparison with other runtimes or other versions

Please note that the SignalR host extensions and worker extensions have the same version.

1. Extensions 1.10.0 works well on .NET 6.
2. Extensions 1.7.0 works well on .NET 7 and .NET 6.
3. Microsoft.Azure.WebJobs.Extensions.SignalRService 1.10.0 itself runs well on .NET 7 (.NET 7 is one of the test target frameworks for .NET Azure SDK NET client libraries).

Therefore, I wonder if the cause is related to the .NET 7 isolated worker runtime.

Dependency changes between extensions 1.7.0 and 1.10.0 .

The dependency topology has not changed.

---
title: Dependency graph for extensions 1.7.0
---
flowchart TD
    subgraph Azure SignalR extensions 1.7.0
    Microsoft.Azure.Functions.Worker.Extensions.SignalRService --> Microsoft.Azure.WebJobs.Extensions.SignalRService
    end
    Microsoft.Azure.WebJobs.Extensions.SignalRService --> Microsoft.Azure.SignalR.Management
    subgraph Azure SignalR SDK 1.15.1
    Microsoft.Azure.SignalR.Management --> Microsoft.Azure.SignalR
    Microsoft.Azure.SignalR.Management --> |PrivateAssets=all|Microsoft.Azure.SignalR.Common 
    Microsoft.Azure.SignalR --> |PrivateAssets=all|Microsoft.Azure.SignalR.Common
    end

---
title: Dependency graph for extensions 1.10.0
---
flowchart TD
    subgraph Azure SignalR extensions 1.10.0
    Microsoft.Azure.Functions.Worker.Extensions.SignalRService --> Microsoft.Azure.WebJobs.Extensions.SignalRService
    end
    Microsoft.Azure.WebJobs.Extensions.SignalRService --> Microsoft.Azure.SignalR.Management
    subgraph Azure SignalR SDK 1.21.2
    Microsoft.Azure.SignalR.Management --> Microsoft.Azure.SignalR
    Microsoft.Azure.SignalR.Management --> |PrivateAssets=all|Microsoft.Azure.SignalR.Common 
    Microsoft.Azure.SignalR --> |PrivateAssets=all|Microsoft.Azure.SignalR.Common
    end

The main changes lie in the Azure SignalR SDK.

1. .NET 7.0 is added to the TFMs of Microsoft.Azure.SignalR.Common .

    <TargetFrameworks>netstandard2.0;netcoreapp3.0;net5.0</TargetFrameworks> <!--The previous TFMs-->
    <TargetFrameworks>netstandard2.0;netcoreapp3.0;net5.0;net7.0</TargetFrameworks> <!--The new TFMs-->
   

2. .NET 6.0 and .NET 7.0 are added to the TFMs of Microsoft.Azure.SignalR.

   <TargetFrameworks>netstandard2.0;netcoreapp3.0;net5.0</TargetFrameworks>  <!--The previous TFMs-->
   <TargetFrameworks>netstandard2.0;netcoreapp3.0;net5.0;net6.0;net7.0</TargetFrameworks>  <!--The newTFMs-->
   

3. No TFM change in Microsoft.Azure.SignalR.Management

I cannot figure out the relation between target framework changes of Azure SignalR SDK and dependency resolution error here. Any insights will be appreciated.

Reproducible project: https://learn.microsoft.com/en-us/azure/azure-signalr/signalr-quickstart-azure-functions-csharp?tabs=isolated-process