Update main.go - handle refresh token

main.go

@@ -117,14 +117,21 @@ func main() {
 		clientSecret := query.Get("client_secret")
 		code := query.Get("code")
 		grantType := query.Get("grant_type")
+		refreshToken := query.Get("refresh_token")
+		fmt.Println(refreshToken)
 		// redirectUri := query.Get("redirect_uri")
 
 		tokenUrl := "https://gw.hml.api.enedis.fr/v1/oauth2/token"
+		
 		data := url.Values{}
 		data.Set("client_id", clientId)
 		data.Set("client_secret", clientSecret)
 		data.Set("code", code)
 		data.Set("grant_type", grantType)
+		if refreshToken != "" {
+			data.Set("refresh_token", refreshToken)
+			data.Set("grant_type", "refresh_token")
+		}
 		
 		client := &http.Client{}
 		req, _ := http.NewRequest("POST", tokenUrl, strings.NewReader(data.Encode()))
@@ -137,23 +144,27 @@ func main() {
 			fmt.Println(err)
 		} else {
 			defer response.Body.Close()
-			// Set Content-Type in response header
-			w.Header().Add("Content-Type", "application/json")
-
-			// Decode response Body using the defined type "TokenResponse"
-			data := TokenResponse{}
-    		decodeError := json.NewDecoder(response.Body).Decode(&data)
-			if decodeError != nil {
-				http.Error(w, decodeError.Error(), 500)
-				return
+			if response.StatusCode >= 200 && response.StatusCode <= 299 {
+				// Set Content-Type in response header
+				w.Header().Add("Content-Type", "application/json")
+
+				// Decode response Body using the defined type "TokenResponse"
+				data := TokenResponse{}
+				decodeError := json.NewDecoder(response.Body).Decode(&data)
+				if decodeError != nil {
+					http.Error(w, decodeError.Error(), 500)
+					return
+				}
+				
+				// Response with json data
+				jsonError := json.NewEncoder(w).Encode(data)
+				if jsonError != nil {
+					http.Error(w, jsonError.Error(), 500)
+					return
+				}
+			} else {
+				http.Error(w, http.StatusText(response.StatusCode), response.StatusCode)
 			}
-			
-			// Response with json data
-			jsonError := json.NewEncoder(w).Encode(data)
-			if jsonError != nil {
-				http.Error(w, jsonError.Error(), 500)
-				return
-        	}
 		}
 	})