Applied DI refactoring in vk module

internal/vk/sender.go

@@ -0,0 +1,55 @@
+package vk
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"log"
+	"math/rand"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+const SendMessageUrl = "https://api.vk.com/method/messages.send"
+
+type Sender interface {
+	Send(userId int64, message string)
+}
+
+type ApiSender struct {
+	Token string
+}
+
+type sendMessageResponse struct {
+	Error errorResponse `json:"error"`
+}
+
+type errorResponse struct {
+	ErrorCode int    `json:"error_code"`
+	ErrorMsg  string `json:"error_msg"`
+}
+
+func (s *ApiSender) Send(userId int64, message string) {
+	randomId := rand.Int63()
+	params := []string{
+		"access_token=" + s.Token,
+		"peer_id=" + strconv.FormatInt(userId, 10),
+		"message=" + url.QueryEscape(message),
+		"v=5.95",
+		"random_id=" + strconv.FormatInt(randomId, 10),
+	}
+	joined := strings.Join(params, "&")
+	reqUrl := SendMessageUrl + "?" + joined
+	resp, err := http.Get(reqUrl)
+	if err != nil || resp.StatusCode != http.StatusOK {
+		log.Printf("[error] Could not Send message. User: %d", userId)
+		return
+	}
+	respContent, _ := ioutil.ReadAll(resp.Body)
+	var unmarshalled sendMessageResponse
+	_ = json.Unmarshal(respContent, &unmarshalled)
+	if unmarshalled.Error.ErrorCode != 0 {
+		log.Printf("[error] Message was not sent. User: %d error message: %s", userId, unmarshalled.Error.ErrorMsg)
+	}
+}