The validation context

Most validation libraries allow you validate a set of data (usually an array) and sometimes a piece of data is validated depending on the context.

Let's say the user must fill a form an order form where it must supply the shipping and billing address. The form has a checkbox "Use a different billing address" which, when checked, shows the billing address details (stree, city etc). Those fields become required only when the user checked that option.

For this reason, the entire validation rules within the Sirius\Validation library are "context-aware". This means the data-set to be validated is passed to each rule.

This can be seen in action in the RequiredWith rule.

The validator receives a set of data to be validated which can be anything (the _POST array, an application model etc). By default the library can handle arrays, ArrayObjects or objects that have the toArray method.

If you use any of these structures the data you pass is converted to an array and wrapped inside an ArrayWrapper. This allows the validation rules to access other information form the context to retrieve it using something like $this->context->getItemValue($aPathToValue)

Validating "non-standard" structures

In order to validate structures that do not meet the criteria above, you have to create your own DataWrapper which would allow the validation rules to extract data from that structure.

Or you can simply implement a toArray method to your objects :)