Composite data sources

It is possible to compose data sent to the layout from several data sources of different types. For example:

{
    "data": {
        "offers": {"$playback-data": 582},
        "coupons": {"$playback-data": 583}
    }
}

Instead of {"$playback-data": 582} the player will substitute the data value from the corresponding source.

The following substitutions can also be passed to composite data:

{
    "data": {"$playback-data": 584},
    "options": {
        // Player ID
        "player_id": {"$player-id": 1},
        // Player tag names
        "player_tags": {"$player-tags": ["Moscow", "ZAO"]}
        // A default value is also passed (used when rendering outside the player context, for example, for
        // previews)
    }
}