Add maximum payload length tests to vpncscript

Signed-off-by: hwipl <[email protected]>

internal/vpncscript/client_test.go

@@ -2,10 +2,12 @@ package vpncscript
 
 import (
 	"path/filepath"
+	"strings"
 	"testing"
 
 	"github.com/telekom-mms/oc-daemon/internal/api"
 	"github.com/telekom-mms/oc-daemon/internal/daemon"
+	"github.com/telekom-mms/oc-daemon/pkg/vpnconfig"
 )
 
 // TestRunClient tests runClient.
@@ -44,4 +46,56 @@ func TestRunClient(t *testing.T) {
 		t.Fatal(err)
 	}
 	server.Stop()
+
+	// helper for config update creation
+	getConfUpdate := func(length int) *daemon.VPNConfigUpdate {
+		exclude := "a.too.long.example.com"
+		conf := vpnconfig.New()
+		conf.Split.ExcludeDNS = []string{exclude}
+		confUpdate := daemon.NewVPNConfigUpdate()
+		confUpdate.Config = conf
+
+		// check length
+		b, err := confUpdate.JSON()
+		if err != nil {
+			t.Fatal(err)
+		}
+		n := length - len(b)
+
+		// increase length to maximum
+		exclude = strings.Repeat("a", n) + exclude
+		conf.Split.ExcludeDNS = []string{exclude}
+
+		return confUpdate
+	}
+
+	// test with maximum payload length
+	server = api.NewServer(config)
+	go func() {
+		for r := range server.Requests() {
+			r.Close()
+		}
+	}()
+	if err := server.Start(); err != nil {
+		t.Fatal(err)
+	}
+	if err := runClient(sockfile, getConfUpdate(api.MaxPayloadLength)); err != nil {
+		t.Fatal(err)
+	}
+	server.Stop()
+
+	// test with more than maximum payload length
+	server = api.NewServer(config)
+	go func() {
+		for r := range server.Requests() {
+			r.Close()
+		}
+	}()
+	if err := server.Start(); err != nil {
+		t.Fatal(err)
+	}
+	if err := runClient(sockfile, getConfUpdate(api.MaxPayloadLength+1)); err == nil {
+		t.Fatal("too long message should return error")
+	}
+	server.Stop()
 }