测试 Azure Functions 时如何调用 ConfigureAppConfiguration

Question

我们最近在 Azure Functions 中添加了 Azure 应用配置，现在我们希望通过测试触发应用配置的启动代码。

我们的函数启动代码是这样的——

    public override void Configure(IFunctionsHostBuilder builder)
    {
        config = Utils.LoadConfig();
        StartupHelper.AddCommonIoCDependencies(builder);
    }

    public override void ConfigureAppConfiguration(IFunctionsConfigurationBuilder builder)
    {
        //How do we trigger this method when testing???
        StartupHelper.AddAzureAppConfiguration(builder);
    }

在运行测试时触发初始配置方法，使用以下-

    private MyFunction_sut;

    [SetUp]
    public void Setup()
    {
        var funcStartup = new Startup();

        var host = new HostBuilder()
            .ConfigureWebJobs(funcStartup.Configure)
            .Build();

        _sut = new MyFunction(...);
    }

这适用于触发配置方法。尽管 HostBuilder 有 ConfigureAppConfiguration 选项，但我不知道如何让它工作。我觉得应该有一种快速简便的方法来处理我在下面的内容。

            var host = new HostBuilder()
            .ConfigureWebJobs(funcStartup.Configure)
            .ConfigureAppConfiguration(x => {
                //What do I put here to call trigger the ConfigureAppConfiguration method at startup?
                //Or is it possible to call my helper "AddAzureAppConfiguration" method that is in a static class?
            })
            .Build();

如果有一种不同的方法来测试 Azure Functions 以添加到不涉及 HosatBuilder 的 Azure 应用程序配置中，那么我很想听听其他人的方法。在网上搜索时，我真的看不到太多，所以我觉得我错过了一些东西。

感谢任何建议！

Answer 1

我需要做类似的事情。不幸的是，完成此操作所需的IFunctionsConfigurationBuilder 的实现被标记为internal，所以我不得不自己复制实现。谢天谢地，它很简单。

// https://github.com/Azure/azure-functions-dotnet-extensions/blob/main/src/Extensions/DependencyInjection/FunctionsConfigurationBuilder.cs
internal class FunctionsConfigurationBuilder : IFunctionsConfigurationBuilder
{
    public FunctionsConfigurationBuilder(IConfigurationBuilder configurationBuilder, WebJobsBuilderContext webJobsBuilderContext)
    {
        ConfigurationBuilder = configurationBuilder ?? throw new ArgumentNullException(nameof(configurationBuilder));
        Context = new DefaultFunctionsHostBuilderContext(webJobsBuilderContext);
    }

    public IConfigurationBuilder ConfigurationBuilder { get; }

    public FunctionsHostBuilderContext Context { get; }
}

// https://github.com/Azure/azure-functions-dotnet-extensions/blob/main/src/Extensions/DependencyInjection/DefaultFunctionsHostBuilderContext.cs
internal class DefaultFunctionsHostBuilderContext : FunctionsHostBuilderContext
{
    public DefaultFunctionsHostBuilderContext(WebJobsBuilderContext webJobsBuilderContext)
        : base(webJobsBuilderContext)
    {
    }
}

这让我可以像这样设置我的测试：

public TestHost()
{
    var webJobsBuilderContext = new WebJobsBuilderContext();
    var startup = new TestStartup();
    var host = new HostBuilder()
        .ConfigureAppConfiguration((context, builder) =>
            startup.ConfigureAppConfiguration(new FunctionsConfigurationBuilder(builder, webJobsBuilderContext))
        )
        .ConfigureWebJobs((context, builder) =>
        {
            webJobsBuilderContext.Configuration = context.Configuration;
            startup.Configure(webJobsBuilderContext, builder);
        })
        .Build();

    ServiceProvider = host.Services;
}

public IServiceProvider ServiceProvider { get; }

而我的测试的Startup 看起来像：

private class TestStartup : Startup
{
    public override void ConfigureAppConfiguration(IFunctionsConfigurationBuilder builder)
    {
        // Do anything else you need to here
        base.ConfigureAppConfiguration(builder);
    }

    public void Configure(WebJobsBuilderContext context, IWebJobsBuilder builder)
    {
        // Do anything else you need to here
        base.Configure(context, builder);
    }
}

差不多就是这样。让我知道是否需要更多详细信息。不幸的是，这并不简单。