How can I validate the total of two refs as below? I would prefer have custom be on the total, yet unsure of how to get the value of the refs in the custom when using Joi.ref.
I can do the following and hang a custom off the entire validation schema, but would prefer to attach it to total.
I don't want to use expression()
I prefer not to change the schema structure as per this answer.
const widgetValidator = Joi.object({
a: Joi.number().integer().min(0).required(),
b: Joi.number().integer().min(1).required(),
total: Joi.number().integer().min(1).required(),
}).custom((value: {a: number; b: number; total: number;}, helpers) => {
if (value.total !== value.a + value.b) {
throw new Error('invalid balance calculation');
}
return value;
},
);
When you install custom on an attribute, it will be a little hard to get whole object values. You have to get it from helpers's states:
Joi.object({
a: Joi.number().integer().min(0).required(),
b: Joi.number().integer().min(1).required(),
total: Joi.number().integer().min(1).required().custom((value, helpers) => {
const { a, b } = helpers.state.ancestors[0];
if (value !== a + b) {
throw new Error('invalid balance calculation');
}
return value;
},
)
})