"Microsoft.Azure.WebJobs.Host: Error indexing method" after upgrade

Question

Hello, I am doing the upgrade of my project from .netcore3.1 to .net7 (isolated process), azure functions from v3 to v4 and CosmoDB to v4. After changing every Microsoft.Azure.WebJobs.Extensions.* reference to the corresponding Microsoft.Azure.Functions.Worker.Extensions.*, trying to run one of my azure function I am still getting this error:

This is what I have in my .csproj file:

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <TargetFramework>net7.0</TargetFramework>
    <AzureFunctionsVersion>v4</AzureFunctionsVersion>
    <OutputType>Exe</OutputType>
    <ImplicitUsings>enabled</ImplicitUsings>
  </PropertyGroup>
  <ItemGroup>
    <PackageReference Include="Autofac" Version="8.0.0" />
    <FrameworkReference Include="Microsoft.AspNetCore.App" />
    <PackageReference Include="Microsoft.ApplicationInsights" Version="2.22.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http.AspNetCore" Version="1.2.0" />
    <PackageReference Include="Microsoft.ApplicationInsights.WorkerService" Version="2.22.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.20.1" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.ApplicationInsights" Version="1.2.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.CosmosDB" Version="4.6.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Storage.Queues" Version="5.2.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Storage.Blobs" Version="6.2.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Tables" Version="1.2.1" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" Version="3.1.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.16.4" />
  </ItemGroup>
  ...
</Project>

And here is how I am using the CosmosDBTrigger:

[Function("StartUploadingProcess")]        
public async Task Run(             
	[CosmosDBTrigger(             
	databaseName: "%CosmosDb_databaseId%",     
	containerName: "SalesInvoices",            
	Connection = "CosmosDb_connectionString",            
	LeaseContainerName = "SalesInvoicesLeases",            
	LeasesContainerThroughput = 500,            
	CreateLeaseContainerIfNotExists = true)]            
	IReadOnlyList<Document> input,             
	FunctionContext executionContext)
{             
	if (input != null && input.Count > 0)
    {...}
	...
}

Can someone help with this issue? Thanks a lot.

Answer 1

@Stefania Grillo I'm glad that you were able to resolve your issue and thank you for posting your solution so that others experiencing the same thing can easily reference this!

I am summarizing the discussion and posting the same as an Answer.

Resolution: Post upgrading the local Cosmos DB emulator and the Function app nugget package Microsoft.Azure.Functions.Worker.Extensions.CosmosDB(4.6.0) to latest versions. Customer is able to run the function successfully.

If you have any other questions or are still running into more issues, please let me know.

Thank you again for your time and patience throughout this issue.

Please accept as Yes if the answer provided is useful, so that you can help others in the community looking for remediation for similar issues.