specify field name instead of "value" - joi

Question

I have to validate value by value instead of passing in a whole schema for multiple values. Based on the docs for single value validation from here
https://hapi.dev/module/joi/
and this sample code
const validator: AnySchema = Joi.string().valid('foo', 'bar').required();
const validationResult: ValidationResult = validator.validate('invalid');
const validationError: ValidationError = validationResult.error;
if (validationError) {
throw validationError;
}
The code will throw an error with the following error message
ValidationError: "value" must be one of [foo, bar]
Is there an easy way I can replace "value" with a specific name? So when I want to validate environment the error message could be
ValidationError: "environment" must be one of [development, production,
test]
or is that only possible when validating multiple values at once?

Answer 1

There is the any.label(name) method that you can use and set a custom label that will be displayed in error messages as well:
any.label(name)
Overrides the key name in error messages.
name - the name of the key.
const schema = {
first_name: Joi.string().label('First Name')
};
You can simply do:
const validator: AnySchema = Joi
.string()
.label('Foo/Bar') // Change tha label using label method
.valid('foo', 'bar')
.required();
const validationResult: ValidationResult = validator.validate('invalid');
const validationError: ValidationError = validationResult.error;
if (validationError) {
throw validationError;
}
will output:
ValidationError: "Foo/Bar" must be one of [foo, bar]