RESEARCH: Better reporting of meta-data

Overview

We need to access all meta-data from a pure QML app (so for example,
QSensor::xxx static methods need to be exported somehow).

Probably have a "system meta-data" object that has the
"availableSensorsChanged" signal (rather than push that on QSensor).

Need a clear guideline. There's spec/doc meta-data (ie. that we expect
people to look up in the documentation or hard-code in their apps).
There's type-specific meta-data (eg. compass calibration). There's
hardware-specific meta-data (eg. how many of the 3 leds should the dipro
hardware turn on).

We should structure the code so there are getters rather than setters.
That way if nobody asks for the meta-data we don't do any work.

It'd be great to get meta-data on a sensor without having to "create"
that sensor. Maybe not such a big deal though...

Implementation Plan

Determine what meta-data we want to have.

Implement backend stuff.

Implement C++ API.

Implement QML API stuff for getting at meta-data.

Notes

Nothing yet.

Research Questions

Do we push spec limits as meta-data?

What type-specific meta-data do we need?

What hardware-specific meta-data do we need?

Can we access everything from QML and C++?

Meta-data is about identifying a sensor (so including human-readable name, description and even icon could be good) and about choosing one sensor over another (eg. this accelerometer is more sensitive than that one and I'm trying to implement a seismograph).

Acceptance Criteria

• A solid understanding of the meta-data we want to repo
• User stories for the implementation