Search Criteria Interface for list filtering

Knowing how to do a proper list filtering to fetch the entities that match a certain lookup is essential for the effective use of getList services across core Magento and possibly custom-coded API's. An example is fetching the list of customers registered within the last 24 hours for the latest added product.

Let's take a look back at our app/code/Foggyline/Slider/etc/webapi.xml file, the bit where we defined the service method="getList". The service class is defined as Foggyline\Slider\Api\SlideRepositoryInterface, which is defined as a preference for the Foggyline\Slider\Model\SlideRepository class. Finally, within the SlideRepository class, we have the actual getList. Method getList is defined as follows:

getList(\Magento\Framework\Api\SearchCriteriaInterface $searchCriteria);

We can see that the getList method takes only one parameter, object instance, that complies with SearchCriteriaInterface called $searchCriteria.

What this means is we already...