crmpixel sending picture is done.

crmpixel.go

+package main
+
+import (
+	"encoding/base64"
+	"fmt"
+	"net/http"
+)
+
+func crmpixel(w http.ResponseWriter, r *http.Request) {
+	b64pixel := "iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH4QcIBzEJ3JY/6wAAAAh0RVh0Q29tbWVudAD2zJa/AAAADUlEQVQI12NgYGBgAAAABQABXvMqOgAAAABJRU5ErkJggg=="
+	pixel, err := base64.StdEncoding.DecodeString(b64pixel)
+	if err == nil {
+		w.Write(pixel)
+	} else {
+		fmt.Fprint(w, "decodig wrong")
+	}
+}

main.go

 	http.HandleFunc("/profile_newly_register", initialRegistrationHandler)
 	http.HandleFunc("/iapi/getAccessToken", supplyAccessToken)
 	http.HandleFunc("/iapi/createWechatQr", iapiCreateWechatQrCode)
+	http.HandleFunc("/crmpixel", crmpixel) //tracking pixel.
 	http.ListenAndServe(":65500", nil)
 }