将 IConfiguration 注入服务集合时环境变量为 null

Question

我正在尝试将我的 azure 函数中的本地配置传递到另一个项目中的 iServiceCollection，该函数与之相关。

我在 .NET 6 中工作

这是我的函数 startup.cs 基于对这个

的回答

[assembly: FunctionsStartup(typeof(DatabaseInit.Startup))]
namespace Edos.DatabaseInit;
public class Startup:FunctionsStartup
{


    public override void Configure(IFunctionsHostBuilder builder)
    {
        var configuration = builder.GetContext().Configuration;
       
        builder.Services.AddInfrastructure(configuration);
       
    }

}

这是我的 local.settings.json

{
  "IsEncrypted": false,
  "ServiceBusConnectionString": "myconnectionstring",
  "Values": {
    "AzureWebJobsStorage": "UseDevelopmentStorage=true",
    "FUNCTIONS_WORKER_RUNTIME": "dotnet"
  }
}

我的函数

public class CosmosInit
{
    private readonly IMessagingService _messagingService;


    public CosmosInit(IMessagingService messagingService)
    {
        _messagingService = messagingService;
        
    }
    [FunctionName("CosmosInit")]
    public async Task<IActionResult> Run(
        [HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req,
        ILogger log)
    {

        await _messagingService.PushToTopic("demotopic", "message");

        return new OkObjectResult(responseMessage);
    }
}

这是我的 Azure 函数的依赖项目中的 Above AddInfrastructure 方法

public static class DependencyInjection
{
    public static IServiceCollection AddInfrastructure(this IServiceCollection services, IConfiguration configuration)
    { 
        var serviceBusConnectionString = Environment.GetEnvironmentVariable("ServiceBusConnectionString");
        if (string.IsNullOrEmpty(serviceBusConnectionString))
        {
            throw new InvalidOperationException(
                "Please specify a valid ServiceBusConnectionString in the Azure Functions Settings or your local.settings.json file.");
        }

        //using AMQP as transport
        services.AddSingleton((s) => {
            return new ServiceBusClient(serviceBusConnectionString, new ServiceBusClientOptions() { TransportType = ServiceBusTransportType.AmqpWebSockets });
        });
        services.AddScoped<IMessagingService, MessagingService>();

        return services;
    }
}

这就是我的方法（在基础设施项目中）

public class MessagingService: IMessagingService
{
    private readonly ServiceBusClient _serviceBusClient;

    public MessagingService(ServiceBusClient serviceBusClient)
    {
        _serviceBusClient = serviceBusClient;
    }
    // the sender used to publish messages to the topic
    
    public async Task<int> PushToTopic(string topic, string serviceMessage)
    {
        var sender = _serviceBusClient.CreateSender(topic);
        var message = new ServiceBusMessage(serviceMessage);
        await sender.SendMessageAsync(message);
        return 1;

    }
}

但是执行的时候没有报错。但在基础设施项目中 Environment.GetEnvironmentVariable("ServiceBusConnectionString") 仅显示为空。我发现它没有从函数 local.settings.json

中获取任何配置

请指出我做错了什么或如何解决这个问题..拜托

Answer 1

根据评论，尝试查找或添加类似

的代码

using Microsoft.Extensions.Configuration;

 Some class {

    ...
        var builder = new ConfigurationBuilder()
        .SetBasePath(Directory.GetCurrentDirectory())
        .AddJsonFile("local.settings.json", optional: false)
        .Build();

        //just to verify
        var conn = builder.GetSection("ServiceBusConnectionString").Get<string>();
        Console.WriteLine(conn);
     ...
}

您可以将它添加到您当前的方法“Configure”中，并保持其余代码不变。或者验证您是否有以前的配置加载点。

默认情况下，appsettings.json 等配置文件不会自动复制到函数应用程序的输出文件夹。更新您的 .csproj 文件以匹配以下示例以确保复制文件。

发件人：https://docs.microsoft.com/en-us/azure/azure-functions/functions-dotnet-dependency-injection

 Some class {

    ...
        var builder = new ConfigurationBuilder()
        .SetBasePath(Directory.GetCurrentDirectory())
        .AddJsonFile("local.settings.json", optional: false)
        .AddEnvironmentVariables() //HERE!!

        //just to verify
        var conn = Environment.GetEnvironmentVariable("ServiceBusConnectionString");
        Console.WriteLine(conn);
     ...
}

将 IConfiguration 注入服务集合时环境变量为 null

Environment variables are null when injecting IConfiguration into service collection

c#

dependency-injection

azure-functions