fix: add ETag header for bot/scraper page. For #4020

webserver/handlers/index.go

@@ -2,6 +2,7 @@ package handlers
 
 import (
 	"bytes"
+	"crypto/md5" // nolint:gosec
 	"encoding/json"
 	"fmt"
 	"net/http"
@@ -199,7 +200,7 @@ func handleScraperMetadataPage(w http.ResponseWriter, r *http.Request) {
 
 	// Set a cache header
 	middleware.SetCachingHeaders(w, r)
-
+	w.Header().Set("ETag", fmt.Sprintf("%x", md5.Sum(b.Bytes()))) // nolint:gosec
 	w.Header().Set("Content-Type", "text/html")
 	if _, err = w.Write(b.Bytes()); err != nil {
 		log.Errorln(err)