Webjob not using appsettings.env.json

Question

.NET Core 2.2, WebJobs SDK 3.0

I have a webjob that I configure like this :

        var environmentName = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") ?? "Development";

        HostBuilder builder = new HostBuilder();
        builder.ConfigureAppConfiguration((context, configApp) => {
            configApp.AddEnvironmentVariables();
            configApp.AddJsonFile("appsettings.json", optional: true);
            configApp.AddJsonFile($"appsettings.{environmentName}.json",optional: false);
        });
        builder.ConfigureHostConfiguration((configApp) => {
            configApp.AddEnvironmentVariables();
            configApp.AddJsonFile("appsettings.json", optional: true);
            configApp.AddJsonFile($"appsettings.{environmentName}.json", optional: false);
        });

I have a appsettings.test.json file deployed to my environment and when I check my environment variable, I have indeed test as the environment.

I can see that the file gets loaded because optional is false and I don't have any exception.

However, when my webjob starts, it doesn't use the storage connection string I have in my appsettings.test.json, it uses the one in appsettings.json

My AppInsights connection doesn't work either and I initializes it like this :

builder.ConfigureLogging((context, b) => {
            b.AddConfiguration(context.Configuration.GetSection("Logging"));
            Console.WriteLine($"App Insight key is {context.Configuration["ApplicationInsights:InstrumentationKey"]}");
            b.AddApplicationInsightsWebJobs(o => o.InstrumentationKey = context.Configuration["ApplicationInsights:InstrumentationKey"]);
        });

When the code runs, the Console shows the App Insights Key that is in the appsettings.json and not the appsettings.test.json

What can I do to force the host to use my appsettings.test.json?

Answer 1

You can extend the existing configuration with additional options. Make sure you have the correct DOTNET_ENVIRONMENT set up as environment variable.

async static Task Main(string[] args)
{
    var builder = Host.CreateDefaultBuilder(args);
    builder.ConfigureWebJobs(b =>
    {
        b.AddAzureStorageCoreServices();
        b.AddAzureStorage();
        b.AddTimers();
    });
    builder.ConfigureServices(services =>
    {
        services.AddScoped<Functions>();
    });
    builder.ConfigureAppConfiguration((context, configurationBuilder) =>
    {
        configurationBuilder
            .AddJsonFile($"appsettings.{context.HostingEnvironment.EnvironmentName}.json", optional: false)
            .AddEnvironmentVariables(); // I prefer environment variables to "override" appsetting files
    });

    IHost host = builder.Build();
    using (host)
    {
        await host.RunAsync();
    }
}

If you are not yet on .net core 3.x, you can also do this:

```csharp
async static Task Main(string[] args)
{
    var builder = Host.CreateDefaultBuilder(args);
    builder.ConfigureWebJobs(b =>
    {
        b.AddAzureStorageCoreServices();
        b.AddAzureStorage();
        b.AddTimers();
    });
    builder.ConfigureServices(services =>
    {
        services.AddScoped<Functions>();
    });
    builder.ConfigureAppConfiguration((context, configurationBuilder) =>
    {
        configurationBuilder
            .AddJsonFile("appsettings.json", optional: false)
            .AddJsonFile($"appsettings.{context.HostingEnvironment.EnvironmentName}.json", optional: false)
            .AddEnvironmentVariables(); // I prefer environment variables to "override" appsetting files
    });

    IHost host = builder.Build();
    using (host)
    {
        await host.RunAsync();
    }
}

Full sample project: https://github.com/LXBdev/WebJob-netcore-sample