For this to work the data need to look like:
{
"route": "test-route,
"startData": datetime(2018, 1, 1, 10, 10, 10),
"points": [
{
"segmentStart": 42,
"longtitude": 0.12,
"lattitude": 42.1
}
]
}
and not like it does for you, which is just flat.
Hope this helps!
btw if you only ever expect one value for points
field, and not a list, you don't need Nested
and you should use Object
instead.