Go laying round tripper HTTP logging

Roundtripper.go

package main

import (
	"bytes"
	"io"
	"log"
	"net/http"
	"net/http/httputil" // For Dumps
)

type debugRoundTripper struct {
	proxiedTransport http.RoundTripper
}

func (drt *debugRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
	// Dump request
	reqDump, err := httputil.DumpRequestOut(req, true)
	if err != nil {
		log.Printf("Error dumping request: %v", err)
	} else {
		log.Printf("--- Request Dump ---\n%s\n--------------------", reqDump)
	}

	resp, err := drt.proxiedTransport.RoundTrip(req)
	if err != nil {
		log.Printf("Error during roundtrip: %v", err)
		return resp, err
	}

	// Dump response
	respDump, err := httputil.DumpResponse(resp, true)
	if err != nil {
		log.Printf("Error dumping response: %v", err)
	} else {
		log.Printf("--- Response Dump ---\n%s\n--------------------", respDump)
	}

	// If you want to log the response body but still return it,
	// you'll need to read it into a buffer and then create a new io.ReadCloser
	if resp.Body != nil {
		bodyBytes, err := io.ReadAll(resp.Body)
		if err != nil {
			log.Printf("Error reading response body for dump: %v", err)
		} else {
			log.Printf("--- Response Body ---\n%s\n---------------------", bodyBytes)
		}
		resp.Body = io.NopCloser(bytes.NewBuffer(bodyBytes)) // Restore body for further reading
	}

	return resp, nil
}

// Use it like this:
// client := &http.Client{
//     Transport: &debugRoundTripper{
//         proxiedTransport: &http.Transport{
//             Proxy: http.ProxyFromEnvironment, // Or http.ProxyURL(...)
//             // ... other transport settings
//         },
//     },
// }