Use NewDecoder instead of read/unmarshal

hems/semp/semp.go

@@ -3,7 +3,6 @@ package semp
 import (
 	"encoding/xml"
 	"fmt"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"os"
@@ -452,12 +451,7 @@ func (s *SEMP) allPlanningRequest() (res []PlanningRequest) {
 func (s *SEMP) deviceControlHandler(w http.ResponseWriter, r *http.Request) {
 	var msg EM2Device
 
-	body, err := ioutil.ReadAll(r.Body)
-	if err == nil {
-		defer r.Body.Close()
-		err = xml.Unmarshal(body, &msg)
-	}
-
+	err := xml.NewDecoder(r.Body).Decode(&msg)
 	s.log.TRACE.Printf("recv: %+v", msg)
 
 	if err != nil {

util/request/functions.go

@@ -72,12 +72,11 @@ func ReadBody(resp *http.Response) ([]byte, error) {
 
 // DecodeJSON reads HTTP response and decodes JSON body if error is nil
 func DecodeJSON(resp *http.Response, res interface{}) error {
-	b, err := ReadBody(resp)
-	if err == nil {
-		err = json.Unmarshal(b, &res)
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		return StatusError{resp: resp}
 	}
 
-	return err
+	return json.NewDecoder(resp.Body).Decode(&res)
 }
 
 // New builds and executes HTTP request and returns the response