tech: avoid using http.DefaultClient

pkg/services/notifications/webhook.go

@@ -5,7 +5,9 @@ import (
 	"context"
 	"fmt"
 	"io/ioutil"
+	"net"
 	"net/http"
+	"time"
 
 	"golang.org/x/net/context/ctxhttp"
 
@@ -22,6 +24,17 @@ type Webhook struct {
 	HttpHeader map[string]string
 }
 
+var netTransport = &http.Transport{
+	Dial: (&net.Dialer{
+		Timeout: 30 * time.Second,
+	}).Dial,
+	TLSHandshakeTimeout: 5 * time.Second,
+}
+var netClient = &http.Client{
+	Timeout:   time.Second * 30,
+	Transport: netTransport,
+}
+
 var (
 	webhookQueue chan *Webhook
 	webhookLog   log.Logger
@@ -68,7 +81,7 @@ func sendWebRequestSync(ctx context.Context, webhook *Webhook) error {
 		request.Header.Set(k, v)
 	}
 
-	resp, err := ctxhttp.Do(ctx, http.DefaultClient, request)
+	resp, err := ctxhttp.Do(ctx, netClient, request)
 	if err != nil {
 		return err
 	}