Provide a way to selectively enable or disable some trackers?

[defagos]

As an SRG SSR analyst I want to be able to take into account background video playback in my reports.

Context

For comScore background video playback must not be tracked, see #25 and associated task #28. It is impossible for all platforms to empirically determine when background video playback should not be tracked, though. On iOS, for example, we can detect the app status but we are not able to automatically determine if the player has no attached layer or is hidden (partially or entirely) by other views.

In cases where video is played while the app is in foreground and no view can be seen, we provide the isTracked Boolean so that apps can disable tracking manually. The issue is that this disables all tracker, even though some trackers should not be disabled because they remain legitimate in such cases. These include e.g.

• Commanders Act, see #26, as the SRG SSR is interested in background playback in general (audio as well of course).
• Diagnostics trackers (e.g. streaming experience reporting).
• Trackers used to save the current playback position into a history (in such cases we likely would like to continue updating the history, even though no video layer is visible).

Acceptance criteria

• Check whether this is an actual need.
• Discuss how this could be achieved from an API perspective. An idea is to associate an id with each tracker and to be able to enable or disable trackers based on ids.
• Create dedicated implementation tasks.

Tasks

• [x] Discuss need and API.
• [x] Create implementation tasks if needed.

[defagos]

A mechanism has been implemented for mandatory / optional tracking support on Apple platforms.

This mechanism should be sufficient for most needs (monitoring, playback position tracking). It is also much simpler than having ids associated with trackers.

Background video playback is currently not really a thing and, even if it was, the app would still be responsible of enabling / disabling tracking, as the app lifecycle will not be observed by Pillarbox itself.