Go HTTP ListenAndServe 记录响应

Question

我想知道在使用 ListenAndServe 时是否有办法记录响应。

据我所知，处理程序无权访问“响应”对象。只是一个 ResponseWriter，所以我不能调用 httputil.DumpResponse。

Answer 1

http.ResponseWriter 是一个接口(interface)。您可以使用嵌入来扩展它以进行日志记录，如下所示。

package main
import (
    "log"
    "net/http"
)

func sampleHandler(w http.ResponseWriter, r *http.Request) {
    w.WriteHeader(http.StatusOK)
    response := []byte("Sample Response")
    w.Write(response)
}

type loggingResponseWriter struct {
    status int
    body   string
    http.ResponseWriter
}

func (w *loggingResponseWriter) WriteHeader(code int) {
    w.status = code
    w.ResponseWriter.WriteHeader(code)
}

func (w *loggingResponseWriter) Write(body []byte) (int, error) {
    w.body = string(body)
    return w.ResponseWriter.Write(body)
}

func responseLogger(h http.Handler) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        loggingRW := &loggingResponseWriter{
            ResponseWriter: w,
        }
        h.ServeHTTP(loggingRW, r)
        log.Println("Status : ", loggingRW.status, "Response : ", loggingRW.body)
    })
}

func main() {
    http.Handle("/", responseLogger(http.HandlerFunc(sampleHandler)))
    http.ListenAndServe(":8080", nil)
}

您可以使用 responseLogger 包装要记录响应的处理函数。