joi.validate не функция
// Try this. Syntax is changed for new version of joi
const schema = Joi.object({ name: Joi.string() .min(6) .required(),
email: Joi.string() .min(6) .required() .email(),
password: Joi.string() .min(6) .required() });
const validation = schema.validate(req.body);
res.send(validation);
VeNOM