application returns json

handler/country.go

@@ -16,7 +16,9 @@ func Chandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	country, code := pkg.GetCountryByCode(vars["country_identifier"], limit)
+	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(code)
+
 	c, _ := json.Marshal(country)
 	if code == 200 {
 		_, _ = fmt.Fprintln(w, string(c))

handler/diag.go

@@ -11,6 +11,8 @@ func Dhandler(w http.ResponseWriter, r *http.Request) {
 	var d pkg.Diag
 	pkg.GetDiag(&d)
 
+	w.Header().Set("Content-Type", "application/json")
+
 	marsh, _ := json.Marshal(d)
 	_, _ = fmt.Fprintln(w, string(marsh))
 }

handler/species.go

@@ -12,6 +12,7 @@ func Shandler(w http.ResponseWriter, r *http.Request) {
 	vars := mux.Vars(r)
 
 	specie, code := pkg.GetSpecies(vars["speciesKey"])
+	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(code)
 
 	s, _ := json.Marshal(specie)