geojson

This module provides a reader to load JSON sources and validate the decoded content as GeoJSON.

readGeoJson

Signature

readGeoJson (source, options)

Description

Reads a JSON source using json.read from @kalisio/common-core/io, then validates the decoded content using validateGeoJson.

The decoded value is always returned in the geojson property when reading and JSON parsing succeed.

Invalid GeoJSON content does not cause the reader to throw. It is reported through the validation result with valid: false and the corresponding errors and warnings.

Parameters

Name	Type	Required	Description
source	string | URL | Blob | File	yes	JSON source accepted by json.read
options	object	no	Options forwarded to json.read

Returns

Type	Description
Promise<object>	An object containing the decoded geojson and the result returned by validateGeoJson

The returned object has the following structure:

{
  geojson,
  valid,
  crs,
  errors,
  warnings,
  statistics
}

Throws

Throws if the source cannot be read.

Throws if the source cannot be parsed as JSON.

Invalid GeoJSON content is not thrown and is instead reported through the validation result.

Examples

const result = await readGeoJson('./data.geojson')

if (result.valid) {
  console.log(result.geojson)
} else {
  console.log(result.errors)
}

// Valid JSON but invalid GeoJSON

const result = await readGeoJson('./invalid.geojson')

// {
//   geojson: { foo: 'bar' },
//   valid: false,
//   errors: [...],
//   warnings: [...],
//   ...
// }