在ASP.Net Core中,我们可以通过中间件来实现请求和响应的日志记录。而对于响应正文的记录,我们可以使用一个自定义模型继承自Stream,并重写WriteAsync方法,在方法中记录响应正文并将数据写回到响应流中。
在中间件中,我们需要按照以下顺序执行以下操作:
下面是一个示例代码,演示了如何在ASP.Net Core中记录响应正文日志:
public class LoggingResponseStream : Stream
{
private readonly Stream _innerStream;
private readonly ILogger _logger;
public LoggingResponseStream(Stream stream, ILogger logger)
{
_innerStream = stream;
_logger = logger;
}
public override async Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
{
_logger.LogInformation($"Response Body: {Encoding.UTF8.GetString(buffer)}");
await _innerStream.WriteAsync(buffer.AsMemory(offset, count), cancellationToken);
}
//省略其他未实现的Stream方法
}
public class LoggingMiddleware
{
private readonly RequestDelegate _next;
private readonly ILogger _logger;
public LoggingMiddleware(RequestDelegate next, ILogger logger)
{
_next = next;
_logger = logger;
}
public async Task Invoke(HttpContext context)
{
var originalBodyStream = context.Response.Body;
using var responseBodyStream = new MemoryStream();
context.Response.Body = responseBodyStream;
await _next(context);
responseBodyStream.Seek(0, SeekOrigin.Begin);
var responseBody = await new StreamReader(responseBodyStream).ReadToEndAsync();
await responseBodyStream.CopyToAsync(originalBodyStream);
_logger.LogInformation($"Response Body: {responseBody}");
}
}
在上面的示例中,我们创建了LoggingResponseStream自定义流模型,并在其中通过ILogger记录响应正文。在LoggingMiddleware中,我们首先拦截请求并创建响应上下文。接着,我们实例化LoggingResponseStream自定义流模型,并将响应上下文的流设置为自定义流模型。然后,我们执行下一个中间件。在执行完中间件后,自定义流模型会记录响应正文并将数据写回到响应流中。最后,在中间件中,我们通过ILogger记录响应正文。