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I am running into this assembly error when the isolated function app is deployed to Azure. I get a 500 internal error every time I hit a request on the app. It works correctly without the signalR functionality that I just added. The signalR service is already running on the Azure environment and is functioning correctly.
The function app is an isolated function.
Here is my csproj package reference:
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<TargetFramework>net6.0</TargetFramework>
<AzureFunctionsVersion>v4</AzureFunctionsVersion>
<OutputType>Exe</OutputType>
<_FunctionsSkipCleanOutput>true</_FunctionsSkipCleanOutput>
</PropertyGroup>
<ItemGroup>
<PackageReference Include="Microsoft.AspNetCore.WebUtilities" Version="2.2.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.8.0-preview1" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" Version="3.0.13" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.OpenApi" Version="1.2.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.SignalRService" Version="1.7.0" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Timer" Version="4.0.1" />
<PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.3.0" />
<PackageReference Include="Microsoft.EntityFrameworkCore" Version="6.0.3" />
<PackageReference Include="Microsoft.Azure.WebJobs.Extensions.SignalRService" Version="1.7.0" />
</ItemGroup>
I shouldn't have to add WebJobs.Extensions.SignalRService since I am using the function worker version of SignalR but I added the Webjobs package just to test if it would fix the error. But the same error continues.
It works fine on my local but I run into errors when deployed to Azure -
The innermost error is:
InnermostType
System.IO.FileNotFoundException
innermostMessage
Could not load file or assembly 'Microsoft.AspNetCore.SignalR.Core, Version=5.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified.
I would appreciate any help asap - I am blocked from testing out our signalR functionality till the deployment issue is fixed.
Thanks,
Nandini
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@Nandini Rao [nandinirao-z] Thank you for reaching out to Microsoft Q&A. Sorry to hear that you are facing this issue. You are correct that you shouldn't need to add package reference Microsoft.Azure.WebJobs.Extensions.SignalRService since worker extension Microsoft.Azure.Functions.Worker.Extensions.SignalRService is correctly referenced above.
Can you let me know how you deploy it to Azure? You can refer sample and try deploying it using Function Core Tools (after removing Microsoft.Azure.WebJobs.Extensions.SignalRService reference). Please let me know if you face issues.
I understand you are blocked with your testing and for quick resolution, would you be able to create a support request with our support team? If you don't have a support plan, let me know so that I can create one-time free technical support for you.
Thanks so much for your response.
We deploy our functions using an ADO pipeline running on terraform scripts.
I have removed the WebJobs.Extensions.SignalRService in the csproj.
On Azure here is some configuration that may be relevant to the issue:
FUNCTIONS_EXTENSION_VERSION ~3
FUNCTIONS_WORKER_RUNTIME dotnet-isolated
Would either of these settings impact this issue?
Our company does have a support plan - can I message you directly?
We got it working! We had to change the FUNCTIONS_EXTENSION_VERSION ~3 (the function runtime settings shows only the history of already set runtime versions, not the full available options) and this solved the runtime assembly issues.
Hope this helps other people!
The change was from ~3 to ~4
@Nandini Rao [nandinirao-z] I am glad that you got it working. Feel free to reach out to us for any other questions.