c# - 如何在 ASP.NET Core 5.0 的 Startup.cs 的 ConfigureServices 方法中执行日志记录
问题描述
构造函数将记录器注入到Startup
早期版本的 ASP.NET Core 中可以正常工作,因为为 Web 主机创建了一个单独的 DI 容器。到目前为止,只为通用主机创建了一个容器,请参阅重大更改公告。
启动.cs
public class Startup
{
/// <summary> The configuration. </summary>
public IConfiguration Configuration { get; }
/// <summary> The web host environment. </summary>
public IWebHostEnvironment WebHostEnvironment { get; }
public Startup(IConfiguration configuration, IWebHostEnvironment webHostEnvironment)
{
Configuration = configuration;
WebHostEnvironment = webHostEnvironment;
}
public void ConfigureServices(IServiceCollection services)
{
services.AddServices(Configuration); // This is a custom method, that adds multiple services to the container.
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILogger<Startup> logger) =>
app.UseComponents(env, Configuration, logger);
}
现在根据MSDN,我已将 Startup.cs 修改如下:
public class Startup
{
/// <summary> The configuration. </summary>
public IConfiguration Configuration { get; }
public ILogger<Startup> Logger { get; set; }
/// <summary> The web host environment. </summary>
public IWebHostEnvironment WebHostEnvironment { get; }
public Startup(IConfiguration configuration, IWebHostEnvironment webHostEnvironment)
{
Configuration = configuration;
WebHostEnvironment = webHostEnvironment;
}
public void ConfigureServices(IServiceCollection services)
{
services.AddSingleton((container) =>
{
var logger = container.GetRequiredService<ILogger<MyService>>();
return new Startup(Configuration, WebHostEnvironment) { Logger = logger };
}); // I know this is incorrect, but that my question- how do I correctly access logger in here?
services.AddServices(Configuration, Logger); // Logger => null
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILogger<Startup> logger) =>
app.UseComponents(env, Configuration, logger);
}
StartupExtension.ConfigureServices.cs
public static partial class StartupExtension
{
#region Internal Method
/// <summary> Adds all the services required by the DemoUsageApp. </summary>
/// <param name="services">The services, <see cref="IServiceCollection"/>.</param>
/// <param name="configuration">The configuration, <see cref="IConfiguration"/>.</param>
/// <param name="logger">The logger, <see cref="ILogger{Startup}"/>.</param>
/// <returns></returns>
internal static IServiceCollection AddServices(this IServiceCollection services, IConfiguration configuration, ILogger logger)
{
services.AddDotNetCoreServices(configuration, logger);
services.AddCrossCuttingServices(configuration, logger);
return services;
}
#endregion Internal Method
#region Private Methods
/// <summary> Adds .NET Core services. </summary>
/// <param name="services">The services, <see cref="IServiceCollection"/>.</param>
/// <param name="configuration">The configuration, <see cref="IConfiguration"/>.</param>
/// <param name="logger">The logger, <see cref="ILogger{Startup}"/>.</param>
/// <returns></returns>
private static IServiceCollection AddDotNetCoreServices(this IServiceCollection services, IConfiguration configuration, ILogger logger)
{
logger.LogInformation("---- Adding .NET Core components ----");
services.AddMvc();
services.AddControllers();
logger.LogInformation("---- Successfully added .NET Core components ----");
return services;
}
/// <summary> Adds Cross-Cutting services. </summary>
/// <param name="services">The services, <see cref="IServiceCollection"/>.</param>
/// <param name="configuration">The configuration, <see cref="IConfiguration"/>.</param>
/// <param name="logger">The logger, <see cref="ILogger{Startup}"/>.</param>
/// <returns></returns>
private static IServiceCollection AddCrossCuttingServices(this IServiceCollection services, IConfiguration configuration, ILogger logger)
{
logger.LogInformation("---- Adding Cross-Cutting components ----");
services.AddSql(configuration, logger); //This is a extension methods, that adds Sql services (which are also completely custom) to the application.
logger.LogInformation("---- Successfully added Cross-Cutting components ----");
return services;
}
#endregion Private Methods
}
问题 -如何在 Startup.cs 的 ConfigureServices 方法中访问 Logger,以便我可以将其传递给其他自定义扩展方法,从而将自定义服务添加到容器中?
注意:为 Microsoft 和 Serilog Logger 请求的解决方案(可选)。
更新 1:正如@MathewBeck 在他的第二条评论中指出的那样,我已经有了以下结构Program.cs
:
public class Program
{
#region Public Methods
/// <summary> Main method, the entry-point of the application. </summary>
/// <param name="args">The args <see cref="string[]"/></param>
public static void Main(string[] args)
{
var host = CreateHostBuilder(args).Build();
var logger = host.Services.GetRequiredService<ILogger<Program>>();
logger.LogInformation("Host created.");
host.Run();
}
/// <summary> Creates the host builder. </summary>
/// <param name="args">The args <see cref="string[]"/></param>
/// <returns></returns>
public static IHostBuilder CreateHostBuilder(string[] args) =>
Host.CreateDefaultBuilder(args)
//.ConfigureLogging(loggingBuilder =>
//{
// loggingBuilder.ClearProviders();
// loggingBuilder.AddConsole();
// loggingBuilder.AddDebug();
// loggingBuilder.AddEventLog();
// loggingBuilder.AddEventSourceLogger();
//})
.ConfigureWebHostDefaults(webBuilder =>
{
webBuilder.UseStartup<Startup>();
webBuilder.UseConfiguration(GetConfiguration());
});
#endregion Public Methods
#region Private Methods
/// <summary> Gets the configuration. </summary>
/// <returns></returns>
private static IConfiguration GetConfiguration()
{
var env = Environment.GetEnvironmentVariable("ASPNETCORE_ENVIRONMENT") ?? "Development";
var builder = new ConfigurationBuilder()
.AddJsonFile("appsettings.json", true, true)
.AddJsonFile($"appsettings.{env}.json", true, true);
return builder.Build();
}
#endregion Private Methods
}
解决方案
ASP.NET 5.0
我使用了 .NET 5.0 中引入的Control Startup 类激活功能 -
引用 MSDN 文档 -
添加了一个额外的UseStartup重载,允许应用程序提供用于控制 Startup 类激活的工厂方法。控制 Startup 类激活对于将附加参数传递给与主机一起初始化的 Startup 很有用
public class Program
{
public static async Task Main(String[] args)
{
var loggerFactory = LoggerFactory
.Create(builder =>
{
builder.ClearProviders();
builder.AddConsole();
});
var logger = loggerFactory.CreateLogger<Program>();
var host = Host.CreateDefaultBuilder()
.ConfigureWebHostDefaults(webBuilder =>
{
webBuilder.UseStartup(context => new Startup(ILogger<Program> logger, /*based on the ctor of startup one can pass the required arguments here*/)
})
.Build();
await host.RunAsync();
}
}
推荐阅读
- javascript - 在 React JS 中调用 jsPlumb.ready 时出现“无法读取未定义的属性 'ready'”
- r - 使用循环在图形上绘制两条或多条线
- postgresql - 使用多个内部和外部联接加速查询
- python - 如果值一次是字符串/整数 dtypes,如何删除 nan 列?
- git - Windows 共享网络文件夹上的 git commit
- python - 将单个数据框列中的不同比例与单个箱线图进行比较
- python - Python 陷入 If 但返回不工作
- python - 使用 Python PIL 时优化保存时间
- c++ - (C++) 当我被教导分离声明和实现时,为什么我看到一些程序员用类来做这件事?
- c - 函数指针,其签名包含一个参数,该参数的类型是指向与第一个函数指针相同类型的指针