Issue running an Azure Function from a package

Updated – see notes below

I have a .NET 8 Azure Function (Windows, not Linux) that is triggered by a CRON timer.

I published it to a Local Folder:

• Configuration : Release
• Target Framework : net8.0
• Target Runtime : win-x64
• Deployment mode : Self-contained

And then deployed it to the wwwroot folder and it’s working fine.

From the "Diagnose and solve problems" pane of the App Service, it gave me a warning that I should deploy this using the "Run Frm Package approach".

I added the configuration value WEBSITE_RUN_FROM_PACKAGE with a value of "1" and that made the wwwroot folder read-only, so that seemed to have been set correctly.

I then deployed the exact same set of files to the "SitePackages" folder and restarted the App Service. It reported that it has restarted successfully.

The only problem is that my functions no longer fires.

I didn’t set the URL because it’s not Linux and is in the default SitePackages folder. The zip is well under the 1GB limit.

Update 18-Dec-2023

Based on the comment by @PravallikaKV, I have some more information.

Isolated rather than In process

.NET 8 wasn’t fully released when this project started, so I went with the isolated model. This is a copy of the csproj file:

<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <TargetFramework>net8.0</TargetFramework>
        <AzureFunctionsVersion>v4</AzureFunctionsVersion>
        <OutputType>Exe</OutputType>
        <ImplicitUsings>enable</ImplicitUsings>
        <Nullable>enable</Nullable>     
    </PropertyGroup>
    <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
        <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
    </PropertyGroup>
    <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
        <TreatWarningsAsErrors>True</TreatWarningsAsErrors>
    </PropertyGroup>
    <ItemGroup>
        <FrameworkReference Include="Microsoft.AspNetCore.App" />
        <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Timer" Version="4.3.0" />
        <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.16.3" OutputItemType="Analyzer" />
        <PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.20.0" />
        <PackageReference Include="Microsoft.Extensions.Http.Polly" Version="8.0.0" />
    </ItemGroup>
    <ItemGroup>
        <None Update="host.json">
            <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
        </None>
        <None Update="local.settings.json">
            <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
            <CopyToPublishDirectory>Never</CopyToPublishDirectory>
        </None>
    </ItemGroup>
    <ItemGroup>
        <Using Include="System.Threading.ExecutionContext" Alias="ExecutionContext" />
    </ItemGroup>
</Project>

Publish profile

Configuration

Application Settings

Function runtime settings

General Settings

Exception

When I run this as a package, I now see the following error message:

Full Exception :
System.NullReferenceException : Object reference not set to an instance of an object.
at Microsoft.Azure.WebJobs.Script.FunctionMetadataManager.GetFallbackWorkerConfig() at //src/WebJobs.Script/Host/FunctionMetadataManager.cs : 129
at Microsoft.Azure.WebJobs.Script.FunctionMetadataManager.LoadFunctionMetadata(Boolean forceRefresh,Boolean includeCustomProviders,IFunctionInvocationDispatcher dispatcher,IList1 workerConfigs) at /_/src/WebJobs.Script/Host/FunctionMetadataManager.cs : 137 at Microsoft.Azure.WebJobs.Script.FunctionMetadataManager.GetFunctionMetadata(Boolean forceRefresh,Boolean applyAllowList,Boolean includeCustomProviders,IList1 workerConfigs) at //src/WebJobs.Script/Host/FunctionMetadataManager.cs : 90
at async Microsoft.Azure.WebJobs.Script.WebHost.Management.FunctionsSyncManager.GetSyncTriggersPayload() at //src/WebJobs.Script.WebHost/Management/FunctionsSyncManager.cs : 312
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at async Microsoft.Azure.WebJobs.Script.WebHost.Management.FunctionsSyncManager.TrySyncTriggersAsync(Boolean isBackgroundSync) at //src/WebJobs.Script.WebHost/Management/FunctionsSyncManager.cs : 125