Azure Functions 2.0 - EventHubTrigger - System.Private.CoreLib: Could not load file or assembly “FunctionsProject.dll”

[manums]

I was able to run function app which has eventhub binding from local as well as from West US2 Consumption plan. From last 4 days, after we moved all our dependent projects to build in x64 and updating all nugets to latest - function app started failing. It does not even start, it fails to load the functionsproject.dll itself. Same issue even If I deploy bits to Consumption Plan.

• Functions Project Name here - EventHubConsumers
• Azure function version - 2.0
• Azure function tools version - 2.28
• Project build configuration - x64
• Net version - NET CORE 2.1
• Visual Studio 2019 & 2017

Nuget dependencies:

<PackageReference Include="Microsoft.ApplicationInsights" Version="2.10.0" />
<PackageReference Include="Microsoft.Azure.Functions.Extensions" Version="1.0.0" />
<PackageReference Include="Microsoft.Azure.WebJobs.Extensions.EventHubs" Version="3.0.6" />
<PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="2.2.0" />
<PackageReference Include="Microsoft.Jarvis" Version="20190426.1.0-rc" />
<PackageReference Include="Microsoft.NET.Sdk.Functions" Version="1.0.29" />
<PackageReference Include="Newtonsoft.Json" Version="12.0.2" />
<PackageReference Include="Polly" Version="7.1.0" /> 

I was not able to pull FusionLog (I gues Functions framework StartLocator have custom logic to load libraries which does not fill fusion log.

I tried debugging LoadFromAssemblyPath(string assemblyPath, bool addProbingPath) in FunctionAssemblyLoadContext.cs which throws this exception. I could see that assembly bin path and verify that my functions app is getting built into that folder itself. I even verified version of the dll and other details by opening up in IlSpy. I cannot make out why assembly (function app dll) could not be loaded when it existed in that path as expected.

• Logged issues on Github: Link

• Trying out older versions of Microsoft.Azure.Webjobs.Extensions.Eventhubs i.e. trying out version 3.0.5

• Clean, delete obj, bin and then running

• Deleting all older versions of AzureFunctionsTools in LocalAppData except for 2.28.

• Running from vs2017

[FunctionName("WriteToStore")]
public async Task Run([EventHubTrigger("activities", Connection = "EventHubConnectionAppSetting", ConsumerGroup = "%ConsumerGroup%")] EventData[] events,
             [EventHub("failed-activities", Connection = "EventHubConnectionAppSetting")]IAsyncCollector<EventData> outputEvents)
{
  //Logic here
}

Upgraded Core tools with:
npm i -g azure-functions-core-tools --unsafe-perm true

More details from Functions Console:

Azure Functions Core Tools (2.7.1505 Commit hash: eb81829)

Function Runtime Version: 2.0.12590.0

[8/4/2019 10:09:25 PM] Building host: startup suppressed:False, configuration suppressed: False

[8/4/2019 10:09:26 PM] A host error has occurred

[8/4/2019 10:09:26 PM] System.Private.CoreLib: Could not load file or assembly 'Microsoft..EventHubConsumers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.

Value cannot be null.

Parameter name: provider

Press any to continue....[8/4/2019 10:09:27 PM] Building host: startup suppressed:False, configuration suppressed: False

[8/4/2019 10:09:27 PM] A host error has occurred

[8/4/2019 10:09:27 PM] System.Private.CoreLib: Could not load file or assembly 'Microsoft..EventHubConsumers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.

Hosting environment: Production

Content root path: D:some\EventHubConsumers\bin\x64\Debug\netcoreapp2.1

Now listening on: http://0.0.0.0:7071

Application started. Press Ctrl+C to shut down.

[8/4/2019 10:09:29 PM] Building host: startup suppressed:False, configuration suppressed: False

[8/4/2019 10:09:29 PM] A host error has occurred

[8/4/2019 10:09:29 PM] System.Private.CoreLib: Could not load file or assembly 'Microsoft.some.EventHubConsumers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'.

[brettsam]

We addressed this with @manums via email. Was an x64 issue. The following other issues helped:

• Create a 64-bit build of func.exe azure-functions-core-tools#117
• Support for dot net core based functions that target x64 Azure-Functions#651

[manums]

I could not follow up on this thread earlier. I could get these issues resolved. I have explained things which I followed on stackoverflow page - here.