c# - 发布为 windows 服务后，在 .net core 3.0 worker 服务上获取 appsettings.json 值

Question

在回答之后: .NET Core 3 Worker Service Settings Dependency Injection

我可以在 Worker.cs 类中获取 Debug 或 Release 中的设置但是当部署为 Windows 服务时，此值返回为 null

Worker.cs

public class Worker : BackgroundService
{
    private readonly ILogger<Worker> _logger;
    private readonly ServiceSettings _serviceSettings;
    private readonly ServiceConfigurations _serviceConfigurations;

    public Worker(ILogger<Worker> logger, IOptions<ServiceConfigurations> serviceConfigurations, IOptions<ServiceSettings> serviceSettings) 
    {
        _logger = logger;
        _serviceConfigurations = serviceConfigurations.Value;

        _logger.LogInformation($"Worker running at: {DateTime.Now}");
        _serviceSettings = serviceSettings.Value;

        string retornoPathLog = null;
        string PathLog = _serviceSettings.PathLog;

        if (!Directory.Exists(PathLog))
        {
            retornoPathLog = "Diretório de LOG " + PathLog;
            Directory.CreateDirectory(PathLog);
        }

        //Configure Serilo for Logging
        Log.Logger = new LoggerConfiguration()
            .MinimumLevel.Information()
            .Enrich.FromLogContext()
            .WriteTo.File(PathLog + "log.txt", rollingInterval: RollingInterval.Day)
            .CreateLogger();

        if (string.IsNullOrEmpty(retornoPathLog) == false)
        {
            Log.Information("[WFoneService - Watch Event] " + retornoPathLog);
        }
    }
}

应用设置.json:

{
  "ConnectionStrings": {
    "WFoneConnection": ""
  },
  "ServiceConfigurations": {
    "UrlSignalrNotification": "urlValue",
    "WatchIp": "ipValue",
    "WatchPort": "portValue"
  },
  "ServiceSettings": {
    "PathLog": "C:\\Log\\"
  },
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Warning",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  }
}

Answer 1

有几种方法可以解决这个问题。

1. 你可以使用 dotnet new worker 模板

dotnet new worker

1. 在 .csproj 中手动将项目类型更改为 Microsoft.NET.Sdk.Worker

<Project Sdk="Microsoft.NET.Sdk.Worker">

1. 在您的 .csproj 中添加您的 appsettings.json 文件并将其复制到输出目录

  <ItemGroup>
    <None Update="appsettings.json">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
  </ItemGroup>

如果您有一个现有项目，我建议您将您的 csproj 转换为我们的 Worker Sdk，或者如果创建一个新项目很简单，请使用 #1。 #3 只是将 appsettings.json 文件复制到您的输出中是一个可怕的技巧，我不推荐这样做。