Return distance in elasticsearch results?

问题:

My question is similar to this one.

Simply, is there a way to return the geo distance when NOT sorting with _geo_distance?

Update: To clarify, I want the results in random order AND include distance.

回答1:

Yes you can, by using a script field.

For instance, assuming your doc have a geo-point field called location, you could use the following:

(note the \u0027 is just an escaped single quote, so \u0027location\u0027 is really 'location')

curl -XGET 'http://127.0.0.1:9200/geonames/_search?pretty=1'  -d '
{
   "script_fields" : {
      "distance" : {
         "params" : {
            "lat" : 2.27,
            "lon" : 50.3
         },
         "script" : "doc[\u0027location\u0027].distanceInKm(lat,lon)"
      }
   }
}
'

# [Thu Feb 16 11:20:29 2012] Response:
# {
#    "hits" : {
#       "hits" : [
#          {
#             "_score" : 1,
#             "fields" : {
#                "distance" : 466.844095463887
#             },
#             "_index" : "geonames_1318324623",
#             "_id" : "6436641_en",
#             "_type" : "place"
#          },
... etc

If you want the _source field to be returned as well, then you can specify that as follows:

curl -XGET 'http://127.0.0.1:9200/geonames/_search?pretty=1'  -d '
{
   "fields" : [ "_source" ],
   "script_fields" : {
      "distance" : {
         "params" : {
            "lat" : 2.27,
            "lon" : 50.3
         },
         "script" : "doc[\u0027location\u0027].distanceInKm(lat,lon)"
      }
   }
}
'

回答2:

To return distance aswel as as all the default fields/source, you could also do this:

To avoid that it sorts by distance (primarily) you just sort by _score (or whatever you want the results sorted by) first.

{
   "sort": [
    "_score",
    {
      "_geo_distance": {
        "location": { 
          "lat":  40.715,
          "lon": -73.998
        },
        "order":         "asc",
        "unit":          "km", 
        "distance_type": "plane" 
      }
    }
  ]
}

回答3:

Great answer by DrTech ... here is an updated version for Elasticsearch 5.x with painless as the script language. I also added "store_fields" to include _source in the result:

curl -XGET 'http://127.0.0.1:9200/geonames/_search?pretty=1'  -d '
{
  "stored_fields" : [ "_source" ],
  "script_fields" : {
    "distance" : {
      "script" : {
        "inline": "doc['location'].arcDistance(params.lat,params.lon) * 0.001",
        "lang": "painless",
        "params": {
          "lat": 2.27,
          "lon": 50.3
        }
      }
    }
  }
}'

回答4:

Since ES 1.3 MVEL is disabled by default so use a query like:

GET some-index/_search
{
  "sort": [
    {
      "_geo_distance": {
        "geo_location": "47.1, 8.1",
        "order": "asc",
        "unit": "m"
      }
    }
  ],
  "query": {
    "match_all": {}
  },
   "script_fields" : {
      "distance" : {
         "lang": "groovy",
         "params" : {
            "lat" : 47.1,
            "lon" : 8.1
         },
         "script" : "doc[\u0027geo_location\u0027].distanceInKm(lat,lon)"
      }
   }
}

see: "lang": "groovy", part