How to use enum values with Joi String validation

You can use valid.

const schema = Joi.object().keys({
  type: Joi.string().valid('ios', 'android'),
});

const myObj = { type: 'none' };
const result = Joi.validate(myObj, schema);
console.log(result);

This gives an error ValidationError: child "type" fails because ["type" must be one of [ios, android]]