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node.jsvalidationjoi

Joi Validation - Field is not required when the condition is not met

I am writing an update endpoint in nodeJs. I want to make sure that additional fields wont be allowed, if certain flags are checked.

all_restaurant: Joi.boolean().required(),
merchant_id: Joi.when('all_restaurant',{'is':false, 
                then: Joi.string().required(), otherwise:Joi.disallow()})

If all_restaurant is true, I need to throw an error when the user tries to include any merchant_id, but it still allowing me to update. I tried using strict() after the field and in the top level but nothing is working. is there any way to achieve that?

Solution

  • You can use Joi.forbidden instead of Joi.disallow:

    const schema = Joi.object({
    all_restaurant: Joi.boolean().required(),
    merchant_id: Joi.string().when('all_restaurant', {
        is: false, 
        then: Joi.required(), 
        otherwise: Joi.forbidden()
    })
})

    As the name suggests, forbidden marks a key as forbidden.