...
"concern_points":[ { "time":1589224427000, "longitude":1.00000919, "latitude":2.00000943 } ]
beocmes becomes this:
"concern_points":[ { "hash":“87e916850d4def3c” } ]
The value of the hash is computed in exactly the same was as on Safe Patths (see above). Note that changing the cost value will result in changes to the hash values produced, so as we tune the cost value to the optimal value, this will require careful co-ordination between Safe Places and Safe Paths.
(potentially for compatibility, Safe Places could output multiple hash values, with different cost values, for each data point - Safe Paths will simply fail to match on any hashes computed with the wrong hash value - while collisions are theoretically possible in practise the odd are almost zero).
For compatibility reasons as we work through this change, our plan is to add the hash first, and then remove the other points later - so for an interim period during MVP1 development, we may output data like this:
...