Fix racy notificationManager (#3714)

* using native http client for notification manager

* handling errors in NotificationsManager

* fixing errors

Co-authored-by: Jeffy Mathew <[email protected]>

apidef/notifications.go

@@ -1,14 +1,18 @@
 package apidef
 
 import (
+	"bytes"
+	"encoding/json"
+	"io/ioutil"
+	"net"
+	"net/http"
 	"time"
 
 	logger "github.com/TykTechnologies/tyk/log"
-
-	"github.com/franela/goreq"
 )
 
 var log = logger.Get()
+var httpClient = initHttpNotificationClient()
 
 // NotificationsManager handles sending notifications to OAuth endpoints to notify the provider of key changes.
 // TODO: Make this more generic
@@ -17,6 +21,20 @@ type NotificationsManager struct {
 	OAuthKeyChangeURL string `bson:"oauth_on_keychange_url" json:"oauth_on_keychange_url"`
 }
 
+func initHttpNotificationClient() *http.Client {
+	var netTransport = &http.Transport{
+		Dial: (&net.Dialer{
+			Timeout: 5 * time.Second,
+		}).Dial,
+		TLSHandshakeTimeout: 5 * time.Second,
+	}
+	return &http.Client{
+		Timeout:   time.Second * 10,
+		Transport: netTransport,
+	}
+
+}
+
 // SendRequest sends the requested package (as a POST) to the defined
 func (n NotificationsManager) SendRequest(wait bool, count int, notification interface{}) {
 	if n.OAuthKeyChangeURL == "" {
@@ -32,23 +50,43 @@ func (n NotificationsManager) SendRequest(wait bool, count int, notification int
 		}
 	}
 
-	req := goreq.Request{
-		Method:      "POST",
-		Uri:         n.OAuthKeyChangeURL,
-		UserAgent:   "Tyk-Gatewy-Notifications",
-		ContentType: "application/json",
-		Body:        notification,
+	var req *http.Request
+	var resp *http.Response
+	var postBody []byte
+	var err error
+
+	postBody, err = json.Marshal(notification)
+	if err != nil {
+		log.Error("Error Marshaling the notification body:", err)
+		return
 	}
+	responseBody := bytes.NewBuffer(postBody)
 
-	req.AddHeader("X-Tyk-Shared-Secret", n.SharedSecret)
+	req, err = http.NewRequest("POST", n.OAuthKeyChangeURL, responseBody)
+	if err != nil {
+		log.Error("Cannot create a new notification request:", err)
+		return
+	}
+	req.Header.Set("User-Agent", "Tyk-Gatewy-Notifications")
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("X-Tyk-Shared-Secret", n.SharedSecret)
 
-	resp, err := req.Do()
+	resp, err = httpClient.Do(req)
 	if err != nil {
 		log.Error("Request failed, trying again in 10s. Error was: ", err)
 		count++
 		go n.SendRequest(true, count, notification)
 		return
 	}
+	defer resp.Body.Close()
+	_, err = ioutil.ReadAll(resp.Body)
+	if err != nil {
+		log.Error("Request failed, trying again in 10s. Error was: ", err)
+		count++
+		n.SendRequest(true, count, notification)
+		return
+	}
+
 	if resp.StatusCode != 200 {
 		log.Error("Request returned non-200 status, trying again in 10s.")
 		count++