Build and validate GeoJSON with Node.js

Table of Contents

• About the Project
• Getting Started
• Usage
• Documentation
  • Global functions
  • Validation
  • Types
• Contributing
• License

About the Project

The GeoJSON.js is designed to build and validate GeoJSON feature collections.

Getting Started

To get started with the GeoJSON.js, install geojsonjs package to your project.

npm i geojsonjs
yarn add geojsonjs

Usage

const geom = {
  type: 'FeatureCollection',
  features: [
    {
      type: 'Feature',
      geometry: {
        type: 'Point',
        coordinates: [11, 22],
      },
    },
  ],
};

import { getFeatureCollection, validate } from 'geojsonjs';
const featureCollection = getFeatureCollection(geom);
const result = validate(featureCollection);

// TypeScript
import {
  getFeatureCollection,
  validate,
  FeatureCollection,
  ValidationResult,
} from 'geojsonjs';
const featureCollection: FeatureCollection = getFeatureCollection(geom);
const result: ValidationResult = validate(featureCollection);

Documentation

Global functions

Name	Returns
parse	FeatureCollection	More info
getGeometries	Geometry[]	More info
getFeatures	Feature[]	More info
getFeatureCollection	FeatureCollection	More info

parse

Accepts array or object of type, coordinates and properties (optional).

Also you can parse GeometryCollection (object or array of objects). In that case instead of coordinates and properties it uses geometries.

Returns feature collection

Example:

import { parse } from 'geojsonjs';

const point1 = { type: 'Point', coordinates: [11, 22] };
const point2 = {
  type: 'Point',
  coordinates: [11, 22],
  properties: { prop1: 'prop1' },
};
const geometryCollection = {
  type: 'GeometryCollection',
  geometries: [{ type: 'Point', coordinates: [11, 22] }],
};

const featureCollection = parse(point1);
const featureCollection2 = parse([point1, point2]);
const featureCollection3 = parse(geometryCollection);

// TypeScript
import { parse, FeatureCollection } from 'geojsonjs';

const featureCollection: FeatureCollection = parse(point1);
const featureCollection2: FeatureCollection = parse([point1, point2]);
const featureCollection3: FeatureCollection = parse(geometryCollection);

getGeometries

Finds and returns all geometries from data.

Supports all geometry types.

Returns array of geometries

Example:

import { getGeometries } from 'geojson';
const geometries = getGeometries(geom);

// TypeScript
import { getGeometries, Geometry } from 'geojson';
const geometries: Geometry[] = getGeometries(geom);

getFeatures

Finds and returns all features from data.

Supports all geometry types.

Returns array of features

Example:

import { getFeatures } from 'geojson';
const features = getFeatures(geom);

// TypeScript
import { getFeatures, Feature } from 'geojson';
const features: Feature[] = getFeatures(geom);

getFeatureCollection

Finds and returns feature collection from data.

Supports all geometry types.

Returns feature collection

Example:

import { getFeatureCollection } from 'geojson';
const featureCollection = getFeatureCollection(geom);

// TypeScript
import { getFeatureCollection, FeatureCollection } from 'geojson';
const featureCollection: FeatureCollection = getFeatureCollection(geom);

Validation

Each validation returns Validation Result response

Name	Params
validate	geom: AllTypes	More info
validateCoordinates	type: string, coordinates: CoordinatesTypes	More info
validateGeometry	geometry: Geometry	More info
validateFeature	feature: Feature	More info
validateFeatures	features: Feature[]	More info
validateFeatureCollection	collection: FeatureCollection	More info
validateGeometryTypes	types: string | string [], geom: AllTypes	More info

validate

Supports all geometry types.

Example:

import { validate } from 'geojsonjs';
const result = validate(geom);

// TypeScript
import { validate, ValidationResult } from 'geojsonjs';
const result: ValidationResult = validate(geom);

validateCoordinates

Accepts type and coordinates.

Example:

import { validateCoordinates } from 'geojsonjs';
const result = validateCoordinates('Point', [11, 12]);

// TypeScript
import { validateCoordinates, ValidationResult } from 'geojsonjs';
const result: ValidationResult = validateCoordinates('Point', [11, 12]);

validateGeometry

Accepts geometry

Example:

const geometry = { type: 'Point', coordinates: [11, 22] };

import { validateGeometry } from 'geojsonjs';
const result = validateGeometry(geometry);

// TypeScript
import { validateGeometry, ValidationResult } from 'geojsonjs';
const result: ValidationResult = validateGeometry(geometry);

validateFeature

Accepts feature

Example:

const feature = {
  type: 'Feature',
  geometry: {
    type: 'Point',
    coordinates: [11, 22],
  },
};

import { validateFeature } from 'geojsonjs';
const result = validateFeature(feature);

// TypeScript
import { validateFeature, ValidationResult } from 'geojsonjs';
const result: ValidationResult = validateFeature(feature);

validateFeatures

Accepts features array

Example:

const features = [
  {
    type: 'Feature',
    geometry: {
      type: 'Point',
      coordinates: [11, 22],
    },
  },
];

import { validateFeatures } from 'geojsonjs';
const result = validateFeatures(features);

// TypeScript
import { validateFeatures, ValidationResult } from 'geojsonjs';
const result: ValidationResult = validateFeatures(features);

validateFeatureCollection

Accepts feature collection

Example:

const featureCollection = {
  type: 'FeatureCollection',
  features: [
    {
      type: 'Feature',
      geometry: {
        type: 'Point',
        coordinates: [11, 22],
      },
    },
  ],
};

import { validateFeatureCollection } from 'geojsonjs';
const result = validateFeatureCollection(featureCollection);

// TypeScript
import { validateFeatureCollection, ValidationResult } from 'geojsonjs';
const result: ValidationResult = validateFeatureCollection(featureCollection);

validateGeometryTypes

Example: Accepts geometry type OR array of geometry types and feature collection

const featureCollection = {
  type: 'FeatureCollection',
  features: [
    {
      type: 'Feature',
      geometry: {
        type: 'Point',
        coordinates: [11, 22],
      },
    },
  ],
};
import { GeometryType, validateGeometryTypes } from 'geojsonjs';
const result = validateGeometryTypes([GeometryType.POINT], featureCollection);

// TypeScript
import {
  GeometryType,
  validateGeometryTypes,
  ValidationResult,
} from 'geojsonjs';
const result: ValidationResult = validateGeometryTypes(
  GeometryType.POINT,
  featureCollection
);

Types

• Geometry types
  • Feature Collection
  • Feature Collections (array)
  • Feature
  • Features (array)
  • Geometry
  • Geometries (array)
  • Geometry collection
  • Geometry collections (array)
• Geometry item types
  • Point
  • MultiPoint
  • LineString
  • MultiLineString
  • Polygon
  • MultiPolygon
• Validation result
• Validation errors

Feature Collection

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "geometry": {
        "type": "Point",
        "coordinates": [11, 22]
      }
    }
  ]
}

Feature Collections (array)

[
  {
    "type": "FeatureCollection",
    "features": [
      {
        "type": "Feature",
        "geometry": {
          "type": "Point",
          "coordinates": [11, 22]
        }
      }
    ]
  },
  {
    "type": "FeatureCollection",
    "features": [
      {
        "type": "Feature",
        "geometry": {
          "type": "Point",
          "coordinates": [33, 44]
        }
      }
    ]
  }
]

Feature

{
  "type": "Feature",
  "geometry": {
    "type": "Point",
    "coordinates": [11, 22]
  }
}

Features (array)

[
  {
    "type": "Feature",
    "geometry": {
      "type": "Point",
      "coordinates": [11, 22]
    }
  },
  {
    "type": "Feature",
    "geometry": {
      "type": "Point",
      "coordinates": [33, 44]
    }
  }
]

Geometry

{
  "type": "Point",
  "coordinates": [11, 22]
}

Geometries (array)

[
  {
    "type": "Point",
    "coordinates": [11, 22]
  },
  {
    "type": "Point",
    "coordinates": [33, 44]
  }
]

Geometry Collection

{
  "type": "GeometryCollection",
  "geometries": [
    { "type": "Point", "coordinates": [11, 22] },
    {
      "type": "LineString",
      "coordinates": [
        [11, 22],
        [22, 33]
      ]
    }
  ]
}

Geometry Collections (array)

[
  {
    "type": "GeometryCollection",
    "geometries": [{ "type": "Point", "coordinates": [11, 22] }]
  },
  {
    "type": "GeometryCollection",
    "geometries": [
      {
        "type": "LineString",
        "coordinates": [
          [11, 22],
          [22, 33]
        ]
      }
    ]
  }
]

Geometry types

import { GeometryType } from 'geojsonjs';

GeometryType.POINT; // Point
GeometryType.MULTI_POINT; // MultiPoint
GeometryType.LINE_STRING; // LineString
GeometryType.MULTI_LINE_STRING; // MultiLineString
GeometryType.POLYGON; // Polygon
GeometryType.MULTI_POLYGON; // MultiPolygon

Validation Result˝

Valid example:

{
  "valid": true
}

Invalid example:

{
  "valid": false,
  "error": "INVALID_TYPE",
  "data": {
    "type": "Pointt"
  }
}

Validation Errors

import { ValidationError } from 'geojsonjs';

ValidationError.EMTPY; // EMTPY
ValidationError.EMPTY_FEATURES; // EMPTY_FEATURES
ValidationError.EMPTY_COORDINATES; // INVALID_COORDINATES
ValidationError.EMPTY_TYPE; // EMPTY_TYPE
ValidationError.INVALID_TYPE; // INVALID_TYPE
ValidationError.INVALID_FEATURES; // INVALID_FEATURES
ValidationError.INVALID_COORDINATES; // INVALID_COORDINATES
ValidationError.INVALID_PROPERTIES; // INVALID_PROPERTIES

Contributing

Contributions are welcome! If you find any issues or have suggestions for improvements, please open an issue or submit a pull request. For more information, see the contribution guidelines.

License

This project is licensed under the MIT License.