将 log4net 与 WebApi 结合使用 - 在整个实例中保持相同的相关 ID

我有一个 LoggingHandler 类，用作消息处理程序来记录（使用 log4net）请求和对我的 WebApi 的响应

public class LoggingMessageHandler : DelegatingHandler
{
    public ILogManager LogManager { get; set; }

    protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, System.Threading.CancellationToken cancellationToken)
    {
        var controllerType = GlobalConfiguration.Configuration.Services
            .GetHttpControllerSelector()
            .SelectController(request)
            .ControllerType;

        var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri);
        var correlationId = request.GetCorrelationId().ToString();

        var requestMessage = await request.Content.ReadAsStringAsync();

        await LogIncommingMessageAsync(controllerType, correlationId, requestInfo, requestMessage.Replace("\r\n", ""));

        var response = await base.SendAsync(request, cancellationToken);

        string responseMessage;

        if (response.IsSuccessStatusCode)
            responseMessage = await response.Content.ReadAsStringAsync();
        else
            responseMessage = response.ReasonPhrase;

        await OutgoingMessageAsync(controllerType, correlationId, requestInfo, responseMessage);

        return response;
    }

    protected async Task LogIncommingMessageAsync(Type type, string correlationId, string requestInfo, string body)
    {
        var logger = LogManager.GetLogger(type);
        await Task.Run(() => logger.Debug("{0} {1} - API Request: \r\n{2}", correlationId, requestInfo, body));
    }

    protected async Task OutgoingMessageAsync(Type type, string correlationId, string requestInfo, string body)
    {
        var logger = LogManager.GetLogger(type);
        await Task.Run(() => logger.Debug("{0} {1} - API Response: \r\n{2}", correlationId, requestInfo, body));
    }
}

ILogManager通过 Autofac 注入（请参阅下面的 Autofac 模块）

我的问题是相关 ID；

如何将其进一步传递到我们的应用程序中？

例如，在另一个包含一些业务逻辑的程序集中，我们希望使用对 LogManager.GetLogger 的调用来获取另一种类型的日志，但由于它源自请求，因此重新使用相同的相关 ID，因此我们可以将我们的日志消息绑定在一起吗？

为了清楚起见，我们的 Autofac 模块如下所示：

public class LoggingAutofacModule : Autofac.Module
{
    protected override void Load(ContainerBuilder builder)
    {
        builder.RegisterType<LogManager>().As<ILogManager>().InstancePerApiRequest();
    }

    protected override void AttachToComponentRegistration(IComponentRegistry registry, IComponentRegistration registration)
    {
        registration.Preparing += OnComponentPreparing;

        var implementationType = registration.Activator.LimitType;
        var injectors = BuildInjectors(implementationType).ToArray();

        if (!injectors.Any())
            return;

        registration.Activated += (s, e) =>
        {
            foreach (var injector in injectors)
                injector(e.Context, e.Instance);
        };
    }

    private static void OnComponentPreparing(object sender, PreparingEventArgs e)
    {
        var t = e.Component.Activator.LimitType;
        e.Parameters =
            e.Parameters.Union(new[] { new ResolvedParameter((p, i) => p.ParameterType == typeof(ILogger), (p, i) => e.Context.Resolve<ILogManager>().GetLogger(t)) });
    }

    private static IEnumerable<Action<IComponentContext, object>> BuildInjectors(Type componentType)
    {
        var properties =
            componentType.GetProperties(BindingFlags.SetProperty | BindingFlags.Public | BindingFlags.Instance)
                         .Where(p => p.PropertyType == typeof(ILogger) && !p.GetIndexParameters().Any())
                         .Where(p =>
                         {
                             var accessors = p.GetAccessors(false);
                             return accessors.Length != -1 || accessors[0].ReturnType == typeof(void);
                         });

        foreach (var propertyInfo in properties)
        {
            var propInfo = propertyInfo;
            yield return (context, instance) => propInfo.SetValue(instance, context.Resolve<ILogManager>().GetLogger(componentType), null);
        }
    }
}

最简单的方法是将其添加到 log4net 逻辑线程上下文的属性中：

LogicalThreadContext.Properties["CorrelationId"] = request.GetCorrelationId();

请注意，由于这是一个logical线程上下文，它将持续存在await点，即使使用不同的线程来恢复请求。