geojson-lookfor

Quickly search any feature from GeoJSON. Can be searched by any keyword. This is an npm module that returns GeoJson that only contains geojson that match the keywords.

Usage

1. Install through npm.

npm i @geolonia/geojson-lookfor

2. Require the module.

const gl = require("@geolonia/geojson-lookfor");

3. Initialize by passing geojson to the GeoJsonlookfor object.

const GeoJsonlookfor = new gl.GeoJsonlookfor(geojson);

4. We can look for features with "bakery" in their properties in the following ways.

GeoJsonlookfor.match('bakery');
console.log(GeoJsonlookfor.getGeoJSON());

When importing:

import { GeoJsonlookfor } from '@geolonia/geojson-lookfor';

const gl = new GeoJsonlookfor(geojson);
const result = gl.match(keyword).getGeoJSON();

console.log(result);

Example

1. Look for a feature with "clothing store".

const gl = require("@geolonia/geojson-lookfor");
const geojson = {
    "type": "FeatureCollection",
    "features": [
      {
        "type": "Feature",
        "properties": {
          "name": "Bistro A",
          "address": "sample address",
          "category": "restaurant"
        },
        "geometry": {
          "coordinates": [
            139.517720985072,
            35.99865685174926
          ],
          "type": "Point"
        }
      },
      {
        "type": "Feature",
        "properties": {
          "name": "sample shop",
          "address": "sample address",
          "category": "clothing store"
        },
        "geometry": {
          "coordinates": [
            139.3008590099202,
            35.97501042924834
          ],
          "type": "Point"
        }
      },
      {
        "type": "Feature",
        "properties": {
          "name": "Bistro B",
          "address": "sample address",
          "category": "restaurant"
        },
        "geometry": {
          "coordinates": [
            139.5371783066526,
            35.941979468748585
          ],
          "type": "Point"
        }
      }
    ]
}

const GeoJsonlookfor = new gl.GeoJsonlookfor(geojson);
const res = GeoJsonlookfor.match('clothing store').getGeoJSON();

console.log(res);

# result
{
  type: 'FeatureCollection',
  features: [ 
    {
        "type": "Feature",
        "properties": {
            "name": "sample shop",
            "address": "sample address",
            "category": "clothing store"
        },
        "geometry": {
            "coordinates": [
            139.3008590099202,
            35.97501042924834
            ],
            "type": "Point"
        }
    }
  ]
}

2. Look for a feature with "restaurant" and "A".

const res = GeoJsonlookfor.match('restaurant').match('A').getGeoJSON();

console.log(res);

# result
{
  type: 'FeatureCollection',
  features: [
    {
        type: 'Feature',
        properties: {
            name: 'Bistro A',
            address: 'sample address',
            category: 'restaurant'
        },
        geometry: {
            coordinates: [ 
                139.517720985072, 
                35.99865685174926 
            ],
            type: 'Point'
        }
    }
  ]
}

Exclude Keys from Search

You can exclude specific property keys from the search by using the excludeKeys option in the match function.
This is useful when you want to ignore certain fields during keyword matching.

Example

const gl = new GeoJsonlookfor(geojson);
// Search for features containing "bakery" but ignore the "name" property
const result = gl.match('bakery', { excludeKeys: ['name'] }).getGeoJSON();

console.log(result);

In this example, even if the name property contains "bakery", it will not be considered in the search. Only other properties will be checked for the keyword.

Filter by geometryType

You can filter features by their geometry type using the geometryType option in the match function.
Only features whose geometry type matches the specified value will be included in the search.

Example

const gl = new GeoJsonlookfor(geojson);
// Search only features with geometry.type === 'Point' and containing 'bakery'
const result = gl.match('bakery', { geometryType: 'Point' }).getGeoJSON();

console.log(result);

Supported geometry types are:
'Point', 'MultiPoint', 'LineString', 'MultiLineString', 'Polygon', 'MultiPolygon'