Shape field type

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The shape data type facilitates the indexing of and searching with arbitrary x, y cartesian shapes such as rectangles and polygons. It can be used to index and query geometries whose coordinates fall in a 2-dimensional planar coordinate system.

You can query documents using this type using shape Query.

Mapping Options

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Like the geo_shape field type, the shape field mapping maps GeoJSON or Well-Known Text (WKT) geometry objects to the shape type. To enable it, users must explicitly map fields to the shape type.

Option Description Default

orientation

Optionally define how to interpret vertex order for polygons / multipolygons. This parameter defines one of two coordinate system rules (Right-hand or Left-hand) each of which can be specified in three different ways. 1. Right-hand rule: right, ccw, counterclockwise, 2. Left-hand rule: left, cw, clockwise. The default orientation (counterclockwise) complies with the OGC standard which defines outer ring vertices in counterclockwise order with inner ring(s) vertices (holes) in clockwise order. Setting this parameter in the geo_shape mapping explicitly sets vertex order for the coordinate list of a geo_shape field but can be overridden in each individual GeoJSON or WKT document.

ccw

ignore_malformed

If true, malformed GeoJSON or WKT shapes are ignored. If false (default), malformed GeoJSON and WKT shapes throw an exception and reject the entire document.

false

ignore_z_value

If true (default) three dimension points will be accepted (stored in source) but only latitude and longitude values will be indexed; the third dimension is ignored. If false, geopoints containing any more than latitude and longitude (two dimensions) values throw an exception and reject the whole document.

true

coerce

If true unclosed linear rings in polygons will be automatically closed.

false

Indexing approach

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Like geo_shape, the shape field type is indexed by decomposing geometries into a triangular mesh and indexing each triangle as a 7 dimension point in a BKD tree. The coordinates provided to the indexer are single precision floating point values so the field guarantees the same accuracy provided by the java virtual machine (typically 1E-38). For polygons/multi-polygons the performance of the tessellator primarily depends on the number of vertices that define the geometry.

IMPORTANT NOTES

CONTAINS relation query - shape queries with relation defined as contains are supported for indices created with ElasticSearch 7.5.0 or higher.

Example
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response = client.indices.create(
  index: 'example',
  body: {
    mappings: {
      properties: {
        geometry: {
          type: 'shape'
        }
      }
    }
  }
)
puts response
PUT /example
{
  "mappings": {
    "properties": {
      "geometry": {
        "type": "shape"
      }
    }
  }
}

This mapping definition maps the geometry field to the shape type. The indexer uses single precision floats for the vertex values so accuracy is guaranteed to the same precision as float values provided by the java virtual machine approximately (typically 1E-38).

Input Structure

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Shapes can be represented using either the GeoJSON or Well-Known Text (WKT) format. The following table provides a mapping of GeoJSON and WKT to Elasticsearch types:

GeoJSON Type WKT Type Elasticsearch Type Description

Point

POINT

point

A single x, y coordinate.

LineString

LINESTRING

linestring

An arbitrary line given two or more points.

Polygon

POLYGON

polygon

A closed polygon whose first and last point must match, thus requiring n + 1 vertices to create an n-sided polygon and a minimum of 4 vertices.

MultiPoint

MULTIPOINT

multipoint

An array of unconnected, but likely related points.

MultiLineString

MULTILINESTRING

multilinestring

An array of separate linestrings.

MultiPolygon

MULTIPOLYGON

multipolygon

An array of separate polygons.

GeometryCollection

GEOMETRYCOLLECTION

geometrycollection

A shape collection similar to the multi* shapes except that multiple types can coexist (e.g., a Point and a LineString).

N/A

BBOX

envelope

A bounding rectangle, or envelope, specified by specifying only the top left and bottom right points.

For all types, both the inner type and coordinates fields are required.

In GeoJSON and WKT, and therefore Elasticsearch, the correct coordinate order is (X, Y) within coordinate arrays. This differs from many Geospatial APIs (e.g., geo_shape) that typically use the colloquial latitude, longitude (Y, X) ordering.

A point is a single coordinate in cartesian x, y space. It may represent the location of an item of interest in a virtual world or projected space. The following is an example of a point in GeoJSON.

POST /example/_doc
{
  "location" : {
    "type" : "point",
    "coordinates" : [-377.03653, 389.897676]
  }
}

The following is an example of a point in WKT:

POST /example/_doc
{
  "location" : "POINT (-377.03653 389.897676)"
}

A linestring defined by an array of two or more positions. By specifying only two points, the linestring will represent a straight line. Specifying more than two points creates an arbitrary path. The following is an example of a LineString in GeoJSON.

POST /example/_doc
{
  "location" : {
    "type" : "linestring",
    "coordinates" : [[-377.03653, 389.897676], [-377.009051, 389.889939]]
  }
}

The following is an example of a LineString in WKT:

POST /example/_doc
{
  "location" : "LINESTRING (-377.03653 389.897676, -377.009051 389.889939)"
}

A polygon is defined by a list of a list of points. The first and last points in each (outer) list must be the same (the polygon must be closed). The following is an example of a Polygon in GeoJSON.

POST /example/_doc
{
  "location" : {
    "type" : "polygon",
    "coordinates" : [
      [ [1000.0, -1001.0], [1001.0, -1001.0], [1001.0, -1000.0], [1000.0, -1000.0], [1000.0, -1001.0] ]
    ]
  }
}

The following is an example of a Polygon in WKT:

POST /example/_doc
{
  "location" : "POLYGON ((1000.0 -1001.0, 1001.0 -1001.0, 1001.0 -1000.0, 1000.0 -1000.0, 1000.0 -1001.0))"
}

The first array represents the outer boundary of the polygon, the other arrays represent the interior shapes ("holes"). The following is a GeoJSON example of a polygon with a hole:

POST /example/_doc
{
  "location" : {
    "type" : "polygon",
    "coordinates" : [
      [ [1000.0, -1001.0], [1001.0, -1001.0], [1001.0, -1000.0], [1000.0, -1000.0], [1000.0, -1001.0] ],
      [ [1000.2, -1001.2], [1000.8, -1001.2], [1000.8, -1001.8], [1000.2, -1001.8], [1000.2, -1001.2] ]
    ]
  }
}

The following is an example of a Polygon with a hole in WKT:

POST /example/_doc
{
  "location" : "POLYGON ((1000.0 1000.0, 1001.0 1000.0, 1001.0 1001.0, 1000.0 1001.0, 1000.0 1000.0), (1000.2 1000.2, 1000.8 1000.2, 1000.8 1000.8, 1000.2 1000.8, 1000.2 1000.2))"
}

IMPORTANT NOTE: WKT does not enforce a specific order for vertices. GeoJSON mandates that the outer polygon must be counterclockwise and interior shapes must be clockwise, which agrees with the Open Geospatial Consortium (OGC) Simple Feature Access specification for vertex ordering.

By default Elasticsearch expects vertices in counterclockwise (right hand rule) order. If data is provided in clockwise order (left hand rule) the user can change the orientation parameter either in the field mapping, or as a parameter provided with the document.

The following is an example of overriding the orientation parameters on a document:

POST /example/_doc
{
  "location" : {
    "type" : "polygon",
    "orientation" : "clockwise",
    "coordinates" : [
      [ [1000.0, 1000.0], [1000.0, 1001.0], [1001.0, 1001.0], [1001.0, 1000.0], [1000.0, 1000.0] ]
    ]
  }
}

The following is an example of a list of GeoJSON points:

POST /example/_doc
{
  "location" : {
    "type" : "multipoint",
    "coordinates" : [
      [1002.0, 1002.0], [1003.0, 2000.0]
    ]
  }
}

The following is an example of a list of WKT points:

POST /example/_doc
{
  "location" : "MULTIPOINT (1002.0 2000.0, 1003.0 2000.0)"
}

The following is an example of a list of GeoJSON linestrings:

POST /example/_doc
{
  "location" : {
    "type" : "multilinestring",
    "coordinates" : [
      [ [1002.0, 200.0], [1003.0, 200.0], [1003.0, 300.0], [1002.0, 300.0] ],
      [ [1000.0, 100.0], [1001.0, 100.0], [1001.0, 100.0], [1000.0, 100.0] ],
      [ [1000.2, 100.2], [1000.8, 100.2], [1000.8, 100.8], [1000.2, 100.8] ]
    ]
  }
}

The following is an example of a list of WKT linestrings:

POST /example/_doc
{
  "location" : "MULTILINESTRING ((1002.0 200.0, 1003.0 200.0, 1003.0 300.0, 1002.0 300.0), (1000.0 100.0, 1001.0 100.0, 1001.0 100.0, 1000.0 100.0), (1000.2 0.2, 1000.8 100.2, 1000.8 100.8, 1000.2 100.8))"
}

The following is an example of a list of GeoJSON polygons (second polygon contains a hole):

POST /example/_doc
{
  "location" : {
    "type" : "multipolygon",
    "coordinates" : [
      [ [[1002.0, 200.0], [1003.0, 200.0], [1003.0, 300.0], [1002.0, 300.0], [1002.0, 200.0]] ],
      [ [[1000.0, 200.0], [1001.0, 100.0], [1001.0, 100.0], [1000.0, 100.0], [1000.0, 100.0]],
        [[1000.2, 200.2], [1000.8, 100.2], [1000.8, 100.8], [1000.2, 100.8], [1000.2, 100.2]] ]
    ]
  }
}

The following is an example of a list of WKT polygons (second polygon contains a hole):

POST /example/_doc
{
  "location" : "MULTIPOLYGON (((1002.0 200.0, 1003.0 200.0, 1003.0 300.0, 1002.0 300.0, 102.0 200.0)), ((1000.0 100.0, 1001.0 100.0, 1001.0 100.0, 1000.0 100.0, 1000.0 100.0), (1000.2 100.2, 1000.8 100.2, 1000.8 100.8, 1000.2 100.8, 1000.2 100.2)))"
}

The following is an example of a collection of GeoJSON geometry objects:

POST /example/_doc
{
  "location" : {
    "type": "geometrycollection",
    "geometries": [
      {
        "type": "point",
        "coordinates": [1000.0, 100.0]
      },
      {
        "type": "linestring",
        "coordinates": [ [1001.0, 100.0], [1002.0, 100.0] ]
      }
    ]
  }
}

The following is an example of a collection of WKT geometry objects:

POST /example/_doc
{
  "location" : "GEOMETRYCOLLECTION (POINT (1000.0 100.0), LINESTRING (1001.0 100.0, 1002.0 100.0))"
}
Envelope
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Elasticsearch supports an envelope type, which consists of coordinates for upper left and lower right points of the shape to represent a bounding rectangle in the format [[minX, maxY], [maxX, minY]]:

POST /example/_doc
{
  "location" : {
    "type" : "envelope",
    "coordinates" : [ [1000.0, 100.0], [1001.0, 100.0] ]
  }
}

The following is an example of an envelope using the WKT BBOX format:

NOTE: WKT specification expects the following order: minLon, maxLon, maxLat, minLat.

POST /example/_doc
{
  "location" : "BBOX (1000.0, 1002.0, 2000.0, 1000.0)"
}

Sorting and Retrieving index Shapes

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Due to the complex input structure and index representation of shapes, it is not currently possible to sort shapes or retrieve their fields directly. The shape value is only retrievable through the _source field.