feat(machine): add validation for machine names to accept only DNS labels

internal/machine/cluster/cluster_test.go

@@ -0,0 +1,28 @@
+package cluster
+
+import (
+	"context"
+	"testing"
+
+	"github.com/psviderski/uncloud/api/pb"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+func TestAddMachine_InvalidName(t *testing.T) {
+	t.Parallel()
+
+	ready := make(chan struct{})
+	close(ready)
+	// Invalid names must be rejected before any store access.
+	c := NewCluster(nil, nil, nil, ready)
+	for _, name := range []string{"VPS1", "worker.example", "rr", "nearest", "c337f00600de51ef4375c9a9a267dba5"} {
+		t.Run("add", func(t *testing.T) {
+			resp, err := c.AddMachine(context.Background(), &pb.AddMachineRequest{Name: name})
+			require.Nil(t, resp)
+			require.Equal(t, codes.InvalidArgument, status.Code(err))
+			require.ErrorContains(t, err, "invalid machine name")
+		})
+	}
+}