How to properly use oneOf and anyOf in Rest Schema?

After some testing in WordPress v6.0.1, it seemed that:

1. We need to set the (default/initial) type of the data.items to null instead of object. (and yes, the type must be set, or else the API response would be invalidated with many “undefined index” notices)

2. For each item, i.e. an array in the oneOf or anyOf, set the type to object.

So your data schema should look like this, but I purposely used anyOf (see explanation below):

'data' => array(
    'type'  => 'array',
    'items' => array(
        'type'  => null,
        'anyOf' => array(
            array(
                'type'       => 'object',
                'properties' => array( ... ),
                'title'      => 'Data única',
            ),
            array(
                'type'       => 'object',
                'properties' => array( ... ),
                'title'      => 'Data corrente',
            ),
        ), // end anyOf
    ), // end items
), // end data

And the reason why I did not use oneOf, is because it caused an error with the code rest_one_of_multiple_matches and the message meta.datas[data][0] matches Data única and Data corrente, but should match only one.

• You could avoid that issue by using unique schemas, e.g. add enum to the dia‘s schema or change the hora_inicio‘s type to number, but that is up to you to decide.