is-like

Constants

GEOMETRY_TYPES

All GeoJSON geometry type strings as an enum-like object.

GEOMETRY_TYPES = {
  POINT: 'Point',
  MULTI_POINT: 'MultiPoint',
  LINESTRING: 'LineString',
  MULTI_LINESTRING: 'MultiLineString',
  POLYGON: 'Polygon',
  MULTI_POLYGON: 'MultiPolygon',
  GEOMETRY_COLLECTION: 'GeometryCollection'
}

FEATURE_TYPES

GeoJSON feature type strings.

FEATURE_TYPES = {
  FEATURE: 'Feature',
  FEATURE_COLLECTION: 'FeatureCollection'
}

CRS_TYPES

GeoJSON CRS (Coordinate Reference System) type strings.

CRS_TYPES = {
  NAME: 'name',
  LINK: 'link'
}

isLikeCRS

Signature

isLikeCRS (object)

Description

Returns true if object is a valid GeoJSON CRS (Coordinate Reference System) object. Supports two types: name (requires a non-empty properties.name string) and link (requires a non-empty properties.href string).

Parameters

Name	Type	Required	Description
object	any	yes	Value to check

Returns

Type	Description
boolean	true if the value is a valid CRS object

Examples

isLikeCRS({ type: 'name', properties: { name: 'urn:ogc:def:crs:OGC:1.3:CRS84' } })
// true

isLikeCRS({ type: 'link', properties: { href: 'https://example.com/crs', type: 'proj4' } })
// true

isLikeCRS({ type: 'name', properties: {} })
// false — missing name

isLikeCRS({ type: 'link', properties: { href: '' } })
// false — empty href

isLikeCRS({ type: 'unknown' })
// false

isLikeCRS(null)
// false

isLikePosition

Signature

isLikePosition (object)

Description

Returns true if object is a valid GeoJSON position: an array of 2 or 3 numbers.

Parameters

Name	Type	Required	Description
object	any	yes	Value to check

Returns

Type	Description
boolean	true if the value is a valid position

Examples

isLikePosition([10, 20])         // true — 2D position
isLikePosition([10, 20, 100])    // true — 3D position (with altitude)
isLikePosition([10])             // false — too short
isLikePosition([10, 20, 30, 40]) // false — too long
isLikePosition([10, 'twenty'])   // false — non-numeric value
isLikePosition(null)             // false

isLikeBBox

Signature

isLikeBBox (object)

Description

Returns true if object is a valid GeoJSON bounding box: an array of 4 or 6 numbers.

Parameters

Name	Type	Required	Description
object	any	yes	Value to check

Returns

Type	Description
boolean	true if the value is a valid bounding box

Examples

isLikeBBox([1, 2, 3, 4])           // true
isLikeBBox([1, 2, 3, 4, 5, 6])     // true — 3D bbox
isLikeBBox([1, 2, 3])              // false — wrong length
isLikeBBox([1, 2, 3, 'four'])      // false — non-numeric value
isLikeBBox(null)                   // false

isLikeGeometry

Signature

isLikeGeometry (object)

Description

Returns true if object is a valid GeoJSON geometry. Checks that the object has a recognized type from GEOMETRY_TYPES, and that it has a coordinates array (or a geometries array for GeometryCollection). Does not deeply validate coordinate values.

Parameters

Name	Type	Required	Description
object	any	yes	Value to check

Returns

Type	Description
boolean	true if the value is a valid GeoJSON geometry

Examples

isLikeGeometry({ type: 'Point', coordinates: [10, 20] })
// true

isLikeGeometry({ type: 'GeometryCollection', geometries: [] })
// true

isLikeGeometry({ type: 'Point' })
// false — missing coordinates

isLikeGeometry({ type: 'Unknown', coordinates: [10, 20] })
// false — unrecognized type

isLikeGeometry(null)
// false

isLikeFeature

Signature

isLikeFeature (object)

Description

Returns true if object is a GeoJSON Feature, i.e. a plain object with type === 'Feature'. Does not validate the geometry or properties fields.

Parameters

Name	Type	Required	Description
object	any	yes	Value to check

Returns

Type	Description
boolean	true if the value is a GeoJSON Feature

Examples

isLikeFeature({ type: 'Feature', geometry: null, properties: {} })
// true

isLikeFeature({ type: 'FeatureCollection', features: [] })
// false

isLikeFeature(null)
// false

isLikeFeatureCollection

Signature

isLikeFeatureCollection (object)

Description

Returns true if object is a GeoJSON FeatureCollection, i.e. a plain object with type === 'FeatureCollection' and a features array. Does not validate the contents of features.

Parameters

Name	Type	Required	Description
object	any	yes	Value to check

Returns

Type	Description
boolean	true if the value is a GeoJSON FeatureCollection

Examples

isLikeFeatureCollection({ type: 'FeatureCollection', features: [] })
// true

isLikeFeatureCollection({ type: 'FeatureCollection' })
// false — missing features array

isLikeFeatureCollection({ type: 'Feature', geometry: null, properties: {} })
// false

isLikeFeatureCollection(null)
// false

isLikeGeoJson

Signature

isLikeGeoJson (object)

Description

Returns true if object is any valid GeoJSON object: a geometry, a Feature, or a FeatureCollection. Delegates to isLikeGeometry, isLikeFeature, and isLikeFeatureCollection.

Parameters

Name	Type	Required	Description
object	any	yes	Value to check

Returns

Type	Description
boolean	true if the value is a valid GeoJSON object

Examples

isLikeGeoJson({ type: 'Point', coordinates: [10, 20] })
// true — geometry

isLikeGeoJson({ type: 'Feature', geometry: null, properties: {} })
// true — Feature

isLikeGeoJson({ type: 'FeatureCollection', features: [] })
// true — FeatureCollection

isLikeGeoJson({ type: 'Unknown' })
// false

isLikeGeoJson(null)
// false