How to insert large polar polygons in elasticsearch?

Question

When inserting a large polygon near the south pole:

"polygon":{
    "type":"polygon",
    "coordinates":[
        [
            [
                -134.97410583496094,
                -61.81480026245117
            ],
            [
                -130.1757049560547,
                -63.236000061035156
            ],
            [
                -125.17160034179688,
                -64.40799713134766
            ],
            [
                -152.0446014404297,
                -75.72830200195312
            ],
            [
                143.52340698242188,
                -77.68319702148438
            ],
            [
                147.41830444335938,
                -75.44519805908203
            ],
            [
                150.2816925048828,
                -73.01909637451172
            ],
            [
                -162.17909240722656,
                -71.5260009765625
            ],
            [
                -134.97410583496094,
                -61.81480026245117
            ]
        ]
    ]
},

, the following error is returned.

{
  "error" : "RemoteTransportException[[ISAAC][inet[/x.x.x.x:9300]][indices:data/write/index]]; nested: MapperParsingException[failed to parse [polygon]]; nested: InvalidShapeException[Self-   intersection at or near point (-142.29442281263474, -71.62101996804898, NaN)]; ",
  "status" : 400
}

The mapping of the type is:

curl -XPUT http://localhost:9200/files/_mapping/polar -d '

{ "polar" : { "properties" : { "startTimeRange" : { "type" : "date"}, "endTimeRange" : { "type" : "date"}, "productShortName" : { "type": "string", "index" : "not_analyzed" }, "polygon" : { "type" : "geo_shape", "tree" : "quadtree", "precision" : "1000m" } } } } '

The intended shape is essential a rectangle crossing the dateline (anti-meridian).

It looks like the shape is being interpreted as a self-intersecting polygon crossing the meridian (0 - Longitude).

What is the best way to represent the intended shape in elasticsearch?

nknize nknize · Accepted Answer · 2015-02-11T21:45:24

Dateline and Pole Crossing is a known issue. Dateline crossing was fixed in ES 1.4.3 but the pole crossing patch will be released in a future version. For now (and this can be a serious PITA for ambiguous polygon's) you'll have to unwrap the Polygon into a MultiPolygon yourself (presumably at the application layer).

Here's an example using your data.

The original self-crossing poly (as seen at the following gist: https://gist.github.com/nknize/ea0e103a22bddae13dfb)

{
    "type" : "Polygon",
    "coordinates":[[
        [
            -134.97410583496094,
            -61.81480026245117
        ],
        [
            -130.1757049560547,
            -63.236000061035156
        ],
        [
            -125.17160034179688,
            -64.40799713134766
        ],
        [
            -152.0446014404297,
            -75.72830200195312
        ],
        [
            143.52340698242188,
            -77.68319702148438
        ],
        [
            147.41830444335938,
            -75.44519805908203
        ],
        [
            150.2816925048828,
            -73.01909637451172
        ],
        [
            -162.17909240722656,
            -71.5260009765625
        ],
        [
            -134.97410583496094,
            -61.81480026245117
        ]
    ]]
}

Corrected version using polar "unwrapping" (seen at the following gist: https://gist.github.com/nknize/8e87ee88d3915498507e)

{
    "type" : "MultiPolygon",
    "coordinates":[[[
        [   
            -180.0,
            -72.092693931
        ],
        [
            -162.17909240722656,
            -71.5260009765625
        ],
        [
            -134.97410583496094,
            -61.81480026245117
        ],
        [
            -130.1757049560547,
            -63.236000061035156
        ],
        [
            -125.17160034179688,
            -64.40799713134766
        ],
        [
            -152.0446014404297,
            -75.72830200195312
        ],
        [    -173.3707512019,
            -90.0
        ],
        [
            -180.0,
            -90.0
        ],
        [     
            -180.0,
            -72.092693931
        ]
      ]], 
      [[
        [     
            173.3707512019,
            -90.0
        ],
        [
            143.52340698242188,
            -77.68319702148438
        ],
        [
            147.41830444335938,
            -75.44519805908203
        ],
        [
            150.2816925048828,
            -73.01909637451172
        ],
        [
            180.0,
            -72.092693931
        ],
        [     
            180.0,
            -90.0
        ],
        [     
            173.3707512019,
            -90.0
        ]
      ]]
    ]
}

Note that the above "corrected" MultiPolygon is a rough calculation (with floating point error) used just for this example.

Not an ideal answer, but I hope it helps!

How to insert large polar polygons in elasticsearch?

1 Answers