Is there a way to validate strings that represent nested object keys in Joi?

Question

I'm using joi@^17.4.0 and have a schema that looks like this:

settings: Joi.object({
  isHidden: Joi.boolean(),
  payoutData: Joi.object({
    email: Joi.string().email(),
  }),
}),

I would like to input the string 'settings.isHidden' or 'settings.payoutData.email' without hard coding each of these strings in the schema. Is there a way that I can make joi know that these strings are valid based on the object schema I already have? Currently, when I try to validate these strings I get a validation error that says those keys are not allowed.

Example object to validate:

{ 'settings.isHidden': false }

I don't think this is possible with Joi alone. Using a variant of your schema, you may need to implement your own validation function that utilises something like Hoek.reach() to extract the rules. — Ankh

Nicholas Carey Nicholas Carey · Accepted Answer · 2022-01-14T00:56:56

Your Joi schema:

settings: Joi.object({
  isHidden: Joi.boolean(),
  payoutData: Joi.object({
    email: Joi.string().email(),
  }),
}),

says that settings (presumably a property of an object) is an object that has two properties:

isHidden, a boolean, and
payoutData, an object with the property email, a string

Your example object

{ 'settings.isHidden': false }

is an object with a single property settings.isHidden and it so fails validation.

Ergo, your object fails validation against the schema.

Is there a way to validate strings that represent nested object keys in Joi?

1 Answers