The DayPI supports a mechanism we call source filtering as a means to limit API results to a specific set of sources, or to eliminate a specified set of sources from returned results.
This recipe describes the two existing methods for invoking source filters in DayPI calls.
In general, source filters can contain either a white list, which ensures that returned results are limited to a specified set of results, or as a black list, which suppresses results from a particular set of sources from return data.
You may include as many as 50 sources in a single source filter
In addition, source filters can be defined in two ways: as a predefined set or as a runtime defined set , which you provide in the context of your DayPI call.