Elasticsearch - MissingMethodException on running distanceInKm on geo_point array - groovy

Question

I have an elasticsearch document which has an array of geo_points. I have created the mapping as:
{
"test": {
"properties": {
"locations": {
"type": "geo_point"
}
}
}
}
Now, I am trying to create a query in which I want to do some processing on the array of geo_points. I have created my query like this:
{
"query": {
"filtered": {
"filter": {
"script": {
"script": "sDistance = doc['locations'].values[0].distanceInKm(28.51818,77.096080);"
}
}
}
}
}
I want to calculate the distance of the point (28.51818,77.096080) from the first element in the locations array.
It is giving me this error:
GroovyScriptExecutionException[MissingMethodException[No signature of method: org.elasticsearch.common.geo.GeoPoint.distanceInKm() is applicable for argument types: (java.lang.Double, java.lang.Double) values: [28.51818, 77.09608]]
I tried using sDistance = doc['locations'][0].distanceInKm(28.51818,77.096080); but it also resulted in the same error.
What am I doing wrong here?
Thanks in advance.

Answer 1

Your script should not retrieve the first geo point by itself, but simply call distanceInKm on the locations field directly, like this:
{
"query": {
"filtered": {
"filter": {
"script": {
"script": "sDistance = doc['locations'].distanceInKm(28.51818,77.096080);"
}
}
}
}
}
Under the hood, the first geo point will be retrieved and the distance will be computed on it.