github.com/lestrrat-go/accesslog

github.com/lestrrat-go/accesslog provides an HTTP middleware that logs accesslogs based on log/slog.

SYNOPSIS

package accesslog_test

import (
  "fmt"
  "log/slog"
  "net/http"
  "net/http/httptest"
  "os"
  "time"

  "github.com/lestrrat-go/accesslog"
)

func Example() {
  al := accesslog.New().
    // Set the clock to a static time to force duration=0 for testing
    Clock(accesslog.StaticClock(time.Time{})).
    Logger(
      slog.New(
        slog.NewJSONHandler(os.Stdout,
          &slog.HandlerOptions{
            ReplaceAttr: func(groups []string, a slog.Attr) slog.Attr {
              switch a.Key {
              case slog.TimeKey:
                // replace time to get static output for testing
                return slog.Time(slog.TimeKey, time.Time{})
              case "remote_addr":
                // replace value to get static output for testing
                return slog.String("remote_addr", "127.0.0.1:99999")
              }
              return a
            },
          },
        ),
      ),
    )

  srv := httptest.NewServer(al.Wrap(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    w.WriteHeader(http.StatusOK)
    _, _ = w.Write([]byte("Hello, World!"))
  })))
  defer srv.Close()

  _, err := http.Get(srv.URL)
  if err != nil {
    fmt.Println(err.Error())
    return
  }

  // OUTPUT:
  // {"time":"0001-01-01T00:00:00Z","level":"INFO","msg":"access","remote_addr":"127.0.0.1:99999","http_method":"GET","path":"/","status":200,"body_bytes_sent":13,"http_referer":"","http_user_agent":"Go-http-client/1.1"}
}

source: accesslog_example_test.go