'html' => ['required_without:markdown', 'string'],
'markdown' => ['required_without:html', 'string'],
'tags' => ['array'],
+ 'priority' => ['integer'],
],
'update' => [
'book_id' => ['integer'],
'html' => ['string'],
'markdown' => ['string'],
'tags' => ['array'],
+ 'priority' => ['integer'],
],
];