fixes

internal/collector/handlers.go

@@ -175,6 +175,8 @@ func (c *Collector) HandleLogs(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	stampFrontendClient(logs, r)
+
 	if err := c.ConsumeLogs(context.Background(), logs); err != nil {
 		log.Printf("failed to consume logs: %v", err)
 		http.Error(w, "failed to consume logs", http.StatusInternalServerError)
@@ -990,3 +992,31 @@ func (c *Collector) HandleNeedleClassify(w http.ResponseWriter, r *http.Request)
 	w.WriteHeader(resp.StatusCode)
 	_, _ = io.Copy(w, resp.Body)
 }
+
+// stampFrontendClient fills in client.address and user_agent.original on
+// browser-originated log records (source=frontend) from the ingest request,
+// since the browser cannot know its own public IP. Values the SDK already
+// sent are kept, and backend services are left alone.
+func stampFrontendClient(logs plog.Logs, r *http.Request) {
+	ip := strings.TrimSpace(clientIP(r))
+	ua := r.Header.Get("User-Agent")
+	rls := logs.ResourceLogs()
+	for i := 0; i < rls.Len(); i++ {
+		sls := rls.At(i).ScopeLogs()
+		for j := 0; j < sls.Len(); j++ {
+			recs := sls.At(j).LogRecords()
+			for k := 0; k < recs.Len(); k++ {
+				a := recs.At(k).Attributes()
+				if v, ok := a.Get("source"); !ok || v.Str() != "frontend" {
+					continue
+				}
+				if _, ok := a.Get("client.address"); !ok && ip != "" {
+					a.PutStr("client.address", ip)
+				}
+				if _, ok := a.Get("browser.userAgent"); !ok && ua != "" {
+					a.PutStr("user_agent.original", ua)
+				}
+			}
+		}
+	}
+}