Introduction to Geolocation Search in Elasticsearch

Firstly, you need to install Elasticsearch on your server or use a cloud-based Elasticsearch service like Elastic Cloud. Make sure you install a compatible version of Elasticsearch with the GeoPoint plugin.

 

Install and Configure the GeoPoint Plugin

Elasticsearch supports geolocation search through the GeoPoint plugin. To install this plugin, you can use the Elasticsearch plugin management tool.

For instance, if you are using Elasticsearch version 7.x, you can run the following command to install the GeoPoint plugin:

bin/elasticsearch-plugin install ingest-geoip

After installing the GeoPoint plugin, you need to configure your index to use the "geo_point" data type for the field that will hold the geolocation information. To do this, you can either edit the mapping of an existing index or create a new index with the configured mapping.

 

Define the Geolocation Field in Mapping

Add the geolocation field to your index and edit the mapping for that field. The geolocation field typically uses the "geo_point" data type. The mapping will define the attributes and options for the geolocation field, such as the precision of the coordinates, format, and more.

Example:

PUT /my_locations_index
{
  "mappings": {
    "properties": {
      "location": {
        "type": "geo_point"
      }
    }
  }
}

 

Edit Data

Add geolocation information to your documents. Typically, geolocation information is represented as a pair of longitude and latitude coordinates. You can obtain this information from users using the Google Maps API or other geolocation data sources.

Example:

PUT /my_locations_index/_doc/1
{
  "name": "Ba Dinh Square",
  "location": {
    "lat": 21.03405,
    "lon": 105.81507
  }
}

 

Perform Geolocation Search

Now that you have geolocation data in your Elasticsearch index, you can perform geolocation search queries to find documents near a specific location or within a certain geographical range. To perform a geolocation search, you can use Elasticsearch's corresponding queries like geo_distance, geo_bounding_box, geo_polygon, etc.

Example: Find locations near the coordinates (21.03405, 105.81507) within a 5km radius.

GET /my_locations_index/_search
{
  "query": {
    "geo_distance": {
      "distance": "5km",
      "location": {
        "lat": 21.03405,
        "lon": 105.81507
      }
    }
  }
}

 

Integrate Google Maps

If you want to integrate Google Maps with Elasticsearch to obtain geolocation information from users, you can use the Google Maps API to retrieve longitude and latitude coordinates based on an address or a location selected by users. Then, you can use this information to add geolocation data to your Elasticsearch index and perform geolocation search queries.

In conclusion, integrating Google Maps with Elasticsearch allows you to leverage geolocation search features in your data, enabling accurate and efficient searching based on geolocation information.