Serilog 记录 web-api 方法，在中间件中添加上下文属性

Question

我一直在努力使用 serilog 记录响应正文有效负载数据，从中间件记录。 我正在开发 WEB API Core 应用程序，将 swagger 添加到端点，我的目标是将每个端点调用记录到 .json带有 serilog 的文件（请求和响应数据）。

对于 GET 请求，应记录响应正文（作为属性添加到 serilog 上下文中），对于 POST 请求，应记录请求正文和响应正文。 我创建了中间件并设法从请求和响应流中正确检索数据，并将其作为字符串获取，但只有 "RequestBody" 被正确记录。

调试时，我可以看到读取请求/响应正文工作正常。

以下是 Program->Main 方法的代码摘录：

Log.Logger = new LoggerConfiguration()
    .ReadFrom.Configuration(configuration)
    .Enrich.FromLogContext()
    .CreateLogger();

以及中间件中的代码：

public async Task Invoke(HttpContext context)
{
    // Read and log request body data
    string requestBodyPayload = await ReadRequestBody(context.Request);

    LogContext.PushProperty("RequestBody", requestBodyPayload);

    // Read and log response body data
    var originalBodyStream = context.Response.Body;
    using (var responseBody = new MemoryStream())
    {
        context.Response.Body = responseBody;
        await _next(context);
        string responseBodyPayload = await ReadResponseBody(context.Response);

        if (!context.Request.Path.ToString().EndsWith("swagger.json") && !context.Request.Path.ToString().EndsWith("index.html"))
        {
            LogContext.PushProperty("ResponseBody", responseBodyPayload);
        }

        await responseBody.CopyToAsync(originalBodyStream);
    }
}

private async Task<string> ReadRequestBody(HttpRequest request)
{
    HttpRequestRewindExtensions.EnableBuffering(request);

    var body = request.Body;
    var buffer = new byte[Convert.ToInt32(request.ContentLength)];
    await request.Body.ReadAsync(buffer, 0, buffer.Length);
    string requestBody = Encoding.UTF8.GetString(buffer);
    body.Seek(0, SeekOrigin.Begin);
    request.Body = body;

    return $"{requestBody}";
}

private async Task<string> ReadResponseBody(HttpResponse response)
{
    response.Body.Seek(0, SeekOrigin.Begin);
    string responseBody = await new StreamReader(response.Body).ReadToEndAsync();
    response.Body.Seek(0, SeekOrigin.Begin);

    return $"{responseBody}";
}

正如我提到的，"RequestBody" 已正确记录到文件中，但 "ResponseBody" 没有任何内容（甚至没有添加为属性） 感谢任何帮助。

Answer 1

从几个帖子中收集信息并根据我的需要对其进行自定义后，我找到了一种将请求和响应正文数据记录为 serilog 日志结构属性的方法。

我没有找到一种方法将请求和响应正文都记录在一个地方（在中间件的Invoke 方法中），但我找到了一种解决方法。由于请求处理管道的性质，我必须这样做：

Startup.cs中的代码：

app.UseMiddleware<RequestResponseLoggingMiddleware>();
app.UseSerilogRequestLogging(opts => opts.EnrichDiagnosticContext = LogHelper.EnrichFromRequest);

• 我使用LogHelper 类来丰富请求属性，正如Andrew Locks post 中所述。

• 当请求处理到达中间件时，在中间件的Invoke 方法中，我正在读取仅请求正文数据，并将此值设置为我添加到的静态字符串属性LogHelper 班级。这样，我已经将请求正文数据读取并存储为字符串，并且可以在调用 LogHelper.EnrichFromRequest 方法时将其添加为丰富器

• 读取请求正文数据后，我正在复制指向原始响应正文流的指针

• 接下来调用await _next(context);，填充context.Response，请求处理从中间件的Invoke方法退出，转到LogHelper.EnrichFromRequest

• 此时 LogHelper.EnrichFromRequest 正在执行，正在读取响应正文数据，并将其设置为丰富器，以及之前存储的请求正文数据和一些附加属性

• 处理返回到中间件Invoke方法（就在await _next(context);之后），并将新内存流（包含响应）的内容复制到原始流中，

以下是上述LogHelper.cs 和RequestResponseLoggingMiddleware.cs 类中的代码：

LogHelper.cs：

public static class LogHelper
{
    public static string RequestPayload = "";

    public static async void EnrichFromRequest(IDiagnosticContext diagnosticContext, HttpContext httpContext)
    {
        var request = httpContext.Request;

        diagnosticContext.Set("RequestBody", RequestPayload);

        string responseBodyPayload = await ReadResponseBody(httpContext.Response);
        diagnosticContext.Set("ResponseBody", responseBodyPayload);

        // Set all the common properties available for every request
        diagnosticContext.Set("Host", request.Host);
        diagnosticContext.Set("Protocol", request.Protocol);
        diagnosticContext.Set("Scheme", request.Scheme);

        // Only set it if available. You're not sending sensitive data in a querystring right?!
        if (request.QueryString.HasValue)
        {
            diagnosticContext.Set("QueryString", request.QueryString.Value);
        }

        // Set the content-type of the Response at this point
        diagnosticContext.Set("ContentType", httpContext.Response.ContentType);

        // Retrieve the IEndpointFeature selected for the request
        var endpoint = httpContext.GetEndpoint();
        if (endpoint is object) // endpoint != null
        {
            diagnosticContext.Set("EndpointName", endpoint.DisplayName);
        }
    }

    private static async Task<string> ReadResponseBody(HttpResponse response)
    {
        response.Body.Seek(0, SeekOrigin.Begin);
        string responseBody = await new StreamReader(response.Body).ReadToEndAsync();
        response.Body.Seek(0, SeekOrigin.Begin);

        return $"{responseBody}";
    }
}

RequestResponseLoggingMiddleware.cs：

public class RequestResponseLoggingMiddleware
{
    private readonly RequestDelegate _next;

    public RequestResponseLoggingMiddleware(RequestDelegate next)
    {
        _next = next;
    }

    public async Task Invoke(HttpContext context)
    {
        // Read and log request body data
        string requestBodyPayload = await ReadRequestBody(context.Request);
        LogHelper.RequestPayload = requestBodyPayload;

        // Read and log response body data
        // Copy a pointer to the original response body stream
        var originalResponseBodyStream = context.Response.Body;

        // Create a new memory stream...
        using (var responseBody = new MemoryStream())
        {
            // ...and use that for the temporary response body
            context.Response.Body = responseBody;

            // Continue down the Middleware pipeline, eventually returning to this class
            await _next(context);

            // Copy the contents of the new memory stream (which contains the response) to the original stream, which is then returned to the client.
            await responseBody.CopyToAsync(originalResponseBodyStream);
        }
    }

    private async Task<string> ReadRequestBody(HttpRequest request)
    {
        HttpRequestRewindExtensions.EnableBuffering(request);

        var body = request.Body;
        var buffer = new byte[Convert.ToInt32(request.ContentLength)];
        await request.Body.ReadAsync(buffer, 0, buffer.Length);
        string requestBody = Encoding.UTF8.GetString(buffer);
        body.Seek(0, SeekOrigin.Begin);
        request.Body = body;

        return $"{requestBody}";
    }
}

Answer 2

接受的答案不是线程安全的。

LogHelper.RequestPayload = requestBodyPayload;

当有多个并发请求时，此分配可能会导致意外的日志记录结果。
我没有使用静态变量，而是将请求正文直接推送到 Serilog 的 LogContext 属性中。

Answer 3

如果登录到该文件，我们可以在 .net core 5.0 中添加以下代码以及来自@Vladimir 的答案。

在 Program.cs 中添加 UseSerilog

public static IHostBuilder CreateHostBuilder(string[] args) =>
    Host.CreateDefaultBuilder(args)
        .ConfigureWebHostDefaults(webBuilder =>
        {
            webBuilder.UseStartup<Startup>();
        })
        .UseSerilog((hostingContext, services, loggerConfig) =>
         loggerConfig.ReadFrom.Configuration(hostingContext.Configuration)
             .WriteTo.Logger(lc => lc.Filter.ByIncludingOnly(Matching.FromSource("Serilog.AspNetCore.RequestLoggingMiddleware")).WriteTo.File(path: "Logs/WebHookLog_.log",
                 outputTemplate: "{Timestamp:o}-{RequestBody}-{ResponseBody}-{Host}-{ContentType}-{EndpointName} {NewLine}", rollingInterval: RollingInterval.Day))
        );

要在 appsettings.json 中添加的字段：

  "Serilog": {
    "MinimumLevel": {
      "Default": "Information",
      "Override": {
        "Default": "Information",
        "Microsoft": "Warning",
        "Microsoft.Hosting.Lifetime": "Information"
      }
    },
    "WriteTo": [
      { "Name": "Console" },
      {
        "Name": "File",
        "Args": {
          "path": "Logs/applog_.log",
          "outputTemplate": "{Timestamp:o} [{Level:u3}] ({SourceContext}) {Message}{NewLine}{Exception}",
          "rollingInterval": "Day",
          "retainedFileCountLimit": 7
        }
      }
    ],
    "Enrich": [ "FromLogContext", "WithMachineName" ],
    "Properties": {
      "Application": "AspNetCoreSerilogDemo"
    }
  },