Use geo-centroid aggregator for geo-hash grids

[clintongormley]

The newly added (elastic/elasticsearch#13846) geo-centroid metric aggregator calcuates where, in a single geo-hash cell, the majority of geo-points are located. This will give a much more natural heat map etc than exists today.

[rashidkpc]

Yay! Thanks for the update, super exited thats available now!

[rashidkpc]

Hrm, just noticed this was implemented as a metric aggregation instead of the original method. Unfortunately it doesn't fit well with our model. Going to have to back burner this until we figure out a nice way to make it fit

[spalger]

Aggs can actually create their own sub-aggs (this is how we support custom sorting by agg).

[philbb]

I would love to see this implemented. Let me know if I can help with making it happen.

[nknize]

@spalger is it easy enough for you to add geo_centroid as a sub aggregator to geohash_grid or do we need to consider reopening elastic/elasticsearch#13912? I'd prefer not reopen, but having this feature blocked may provide enough reason to add the optional geo_centroid parameter back to geohash_grid. If its enough of a pain for our kibana team it will be more of a pain for the community? /cc @clintongormley

[mbertani]

I am a bit confused by this thread, is there a way to use geo_centroid with the tile map visualization in Kibana already? Or are they using something else than Kibana to render the map in this presentation in section GeoCentroid Agg (almost at the end). Whatever I try adding as a json input to a tile map in Kibana, I get the code inside the geohash_grid definition, and not as a subaggregation. And the geo_centroid bit is ignored.

[nknize]

I don't think geo_centroid is being used in kibana yet? @epixa would know more.

[epixa]

@nknize That is correct, we do not currently use geo_centroid in Kibana.

[mbertani]

Ok, thanks for the feedback! Looking forward to having this feature available in kibana.

[JacobBrandt]

Maybe I'm missing something but why can't we just create a new metric aggregation for this feature? Then people can add it to their visualizations however they want. I played around and created a new metric aggregation type. I then modified the geo json aggregation response code to check for this aggregation and change the geometry coordinates for the returned feature point to the centroid if it existed otherwise the coordinates remain the same like before and come from the geo hash.

So now if you want the geo_centroid aggregation metric you have to add the metric in the visualization which I think makes sense. Here I changed a tile map that I use to include it as a metric.

And now my circle markers are positioned based on the geo centroid of each bucket instead of the center of the geo hash grid.

[thomasneirynck]

We're planning to make this the new default behavior for Kibana. We'll introduce this functionality as part of a larger map enhancement effort.