Group by nested fields

[raitraidma]

It would be great to be able to group by nested fields.

For example, when data is structured like that:

mutation {
  schema {
    name: string @index(hash) .
    geoPoint: geo .
  }

  set {
    _:company1 <name> "Company A" .
    _:company1 <pickupFrom> _:company1_pickup_from .
    _:company1 <deliverTo> _:company1_deliver_to .
    _:company1_pickup_from <geoPoint> "{'type':'Point','coordinates':[0.0,0.0]}" .
    _:company1_deliver_to <geoPoint> "{'type':'Point','coordinates':[10.0,11.0]}" .

    _:company2 <name> "Company A" .
    _:company2 <pickupFrom> _:company2_pickup_from .
    _:company2 <deliverTo> _:company2_deliver_to .
    _:company2_pickup_from <geoPoint> "{'type':'Point','coordinates':[0.0,0.0]}" .
    _:company2_deliver_to <geoPoint> "{'type':'Point','coordinates':[10.0,11.0]}" .

    _:company3 <name> "Company A" .
    _:company3 <pickupFrom> _:company3_pickup_from .
    _:company3 <deliverTo> _:company3_deliver_to .
    _:company3_pickup_from <geoPoint> "{'type':'Point','coordinates':[0.0,0.0]}" .
    _:company3_deliver_to <geoPoint> "{'type':'Point','coordinates':[13.0,14.0]}" .
  }
}

Query might be something like that:

{
  q(func: eq(name, "Company A")) @groupby(<pickupFrom>.<geoPoint>,  <deliverTo>.<geoPoint>) {
    count(_uid_)
  }
}

Expected result something like that:

[
    {
        pickupFrom: {'type':'Point','coordinates':[0.0,0.0]},
        deliverTo: {'type':'Point','coordinates':[10.0,11.0]},
        count: 2
    },
    {
        pickupFrom: {'type':'Point','coordinates':[0.0,0.0]},
        deliverTo: {'type':'Point','coordinates':[13.0,14.0]},
        count: 1
    }
]