Changed log printing on error only

vk/message.go

@@ -1,6 +1,7 @@
 package vk
 
 import (
+	"encoding/json"
 	"io/ioutil"
 	"log"
 	"math/rand"
@@ -24,10 +25,13 @@ func Message(userId int64, message string) {
 	paramString := strings.Join(params, "&")
 	resp, err := http.Get(SendMessageUrl + "?" + paramString)
 	if err != nil || resp.StatusCode != http.StatusOK {
-		log.Print("Could not send message\n user: %lld", userId)
+		log.Printf("Could not send message\n user: %d", userId)
 		return
 	}
 	responseBytes, _ := ioutil.ReadAll(resp.Body)
-	log.Printf("Message sent\n user: %d\n message: %s\n server response: %s", userId, message,
-		string(responseBytes))
+	var response SendMessageResponse
+	_ = json.Unmarshal(responseBytes, &response)
+	if response.Error.ErrorCode != 0 {
+		log.Printf("Message was not sent message\n user: %d\n error message: %s", userId, response.Error.ErrorMsg)
+	}
 }

vk/structs.go

@@ -11,3 +11,12 @@ type UserMessage struct {
 	Body   string `json:"text"`
 	UserId int64  `json:"peer_id"`
 }
+
+type SendMessageResponse struct {
+	Error ErrorResponse `json:"error"`
+}
+
+type ErrorResponse struct {
+	ErrorCode int    `json:"error_code"`
+	ErrorMsg  string `json:"error_msg"`
+}