第一步，添加Nuget包引用
Microsoft.AspNetCore.MiddlewareAnalysis和Microsoft.Extensions.DiagnosticAdapter，前者是分析记录中间件核心代码实现后者是用来接收日志输出的，由于是用的DiagnosticSource方式记录日志，所以需要使用DiagnosticListener对象的SubscribeWithAdapter方法来订阅。
第二步，实现一个分析诊断适配器
public class AnalysisDiagnosticAdapter
{
private readonly ILogger<AnalysisDiagnosticAdapter> _logger;
public AnalysisDiagnosticAdapter(ILogger<AnalysisDiagnosticAdapter> logger
{
_logger = logger;
}
[DiagnosticName("Microsoft.AspNetCore.MiddlewareAnalysis.MiddlewareStarting"]
public void OnMiddlewareStarting(HttpContext httpContext, string name, Guid instance, long timestamp
{
_logger.LogInformation($"中间件-启动: '{name}'; Request Path: '{httpContext.Request.Path}'";
}
[DiagnosticName("Microsoft.AspNetCore.MiddlewareAnalysis.MiddlewareException"]
public void OnMiddlewareException(Exception exception, HttpContext httpContext, string name, Guid instance, long timestamp, long duration
{
_logger.LogInformation($"中间件-异常: '{name}'; '{exception.Message}'";
}
[DiagnosticName("Microsoft.AspNetCore.MiddlewareAnalysis.MiddlewareFinished"]
public void OnMiddlewareFinished(HttpContext httpContext, string name, Guid instance, long timestamp, long duration
{
_logger.LogInformation($"中间件-结束: 耗时[{duration/10000}] '{name}'; Status: '{httpContext.Response.StatusCode}'";
}
}
第三步，注册相关服务来启用分析中间件的功能
- 注册中间件分析服务
var builder = WebApplication.CreateBuilder(args;
builder.Services.AddMiddlewareAnalysis(;
- 订阅我们的分析诊断适配器
var listener = app.Services.GetRequiredService<DiagnosticListener>(;
var observer = ActivatorUtilities.CreateInstance<AnalysisDiagnosticAdapter>(app.Services;
using var disposable = listener.SubscribeWithAdapter(observer;
这样基本就完成了分析记录中间件的功能，启动程序看看效果
var builder = WebApplication.CreateBuilder(args;
// 新增的下面这句代码
builder.Services.Insert(0, ServiceDescriptor.Transient<IStartupFilter, AnalysisStartupFilter>(;
builder.Services.AddMiddlewareAnalysis(;
现在再来看看效果，发现变成8个中间件了多了四个
简单三步就可以知道一个请求到底执行了哪些中间件还是挺方便的。想知道实现原理可以去看看Microsoft.AspNetCore.MiddlewareAnalysis这个库，一共才四个文件看起来不费事。