[RFC] - Geo Bound Aggregation on Geo Shape Field

[navneet1v]

The purpose of this RFC (request for comments) is to gather community feedback on a proposal to allow OpenSearch users to facilitate Geo Bounds Aggregations over the GeoShape data type. This RFC is in continuation with #84.

Geo Bounds Aggregation

A metric aggregation that computes the bounding box containing all geo values for a field.

Aggregation Schema

{
  "aggs/aggregations": {
    "<user-provided-aggregation-name>": {
      "geo_bounds": {
        "field": "<field-name-on-which-aggregation-will-be-performed>",
        "wrap_longitude": <true/false> // default value is true
      }
    }
  }
}

Input Parmeters:

• wrap_longitude: It will be an optional parameter which specifies whether the bounding box should be allowed to overlap the international date line. The default value is true. If wrap_longitude is set to true (the default), the bounding box can overlap the international date line and return a bounds where the top_left longitude is larger than the top_right longitude.

Example

Index Creation

PUT /myexample
{
  "mappings": {
    "properties": {
      "geometry": {
        "type": "geo_shape"
      }
    }
  }
}

Index Data

POST /myexample/_bulk?refresh
{"index":{"_id":1}}
{"name": "Science Museum", "geometry": "POINT(4.912350 52.374081)" }
{"index":{"_id":2}}
{"name": "MyHouse", "geometry": { "type": "Polygon", "coordinates": [ [ [ 4.965305328369141, 52.39347642069457 ], [ 4.966979026794433, 52.391721758934835 ], [ 4.969425201416015, 52.39238958618537 ], [ 4.967944622039794, 52.39420969150824 ], [ 4.965305328369141, 52.39347642069457 ] ] ] } }

Run Aggregation

POST /myexample/_search?size=0
{
  "aggregations": {
    "viewport": {
      "geo_bounds": {
        "field": "geometry",
        "wrap_longitude": true
      }
    }
  }
}

Output of Aggregation

{
....
  "aggregations": {
    "viewport": {
      "bounds": {
        "top_left": {
          "lat": 52.39420966710895,
          "lon": 4.912349972873926
        },
        "bottom_right": {
          "lat": 52.374080987647176,
          "lon": 4.969425117596984
        }
      }
    }
  }
}

Launch Dates

We are working to identify the exact version of OpenSearch in which this aggregation will be launched. Will add the details soon.

References

1. GeoBound on Geo Points: https://opensearch.org/docs/latest/opensearch/metric-agg/#geo_bound
2. RFC for Aggregations: [RFC] - Implement Aggregations on Geo Shape Field #84