Search Geospatially

Overview

In this guide, you can learn how to search geospatial data by using the Rust driver. Geospatial data represents a geographic location on the surface of the Earth or on a Euclidean plane.

Examples of geospatial data include:

• Locations of movie theaters

• Borders of countries

• Routes of bicycle rides

• Dog exercise areas in New York City

• Points on a graph

This guide includes the following sections:

• Store Geospatial Data describes the data formats you can use to represent geospatial data

• Geospatial Indexes describes how to create an index on fields storing geospatial data

• Geospatial Queries describes how to query geospatial data stored in indexed fields

• Additional Information provides links to resources and API documentation for types and methods mentioned in this guide

Store Geospatial Data

All geospatial data in MongoDB is stored in one of the following formats:

• GeoJSON, a format that represents geospatial data on an Earth-like sphere

• Legacy Coordinate Pair, a format that represents geospatial data on a Euclidean plane

let coords = vec! [-73.986805, 40.7620853];

let capital = vec! [-77.0369, 38.9072];

Geospatial Indexes

Before querying geospatial data, you must create an index that corresponds to the data format. The following index types enable geospatial queries:

• 2dsphere for GeoJSON data

• 2d for legacy coordinate pairs

The following sections on 2dsphere and 2d indexes include code examples that use the theaters collection in the sample_mflix database from the Atlas sample data.

let index = IndexModel::builder()
    .keys(doc! { "location.geo": "2dsphere" })
    .build();
let idx = my_coll.create_index(index).await?;
println!("Created index:\n{}", idx.index_name);

Created index:
location.geo_"2dsphere"

let index = IndexModel::builder()
    .keys(doc! { "location.geo.coordinates": "2d" })
    .build();
let idx = my_coll.create_index(index).await?;
println!("Created index:\n{}", idx.index_name);

Created index:
location.geo.coordinates_"2d"

Geospatial Queries

After creating a 2dsphere or 2d index on fields containing geospatial data, you can perform geospatial queries that access those fields.

To query geospatial data, create a query filter with a field name and a geospatial query operator. You can specify options for certain geospatial query operators to limit the documents returned.

The following sections on geospatial queries include code examples that use the theaters collection in the sample_mflix database from the Atlas sample data. Assume that the theaters collection has a 2dsphere index on the location.geo field.

let mongodb = vec! [-73.986805, 40.7620853];
let query = doc! {"location.geo": 
    doc! { "$near": {
        "$geometry": {
            "type": "Point", "coordinates": mongodb,
            },
        "$maxDistance": 1000,
        }
    }
};
let mut cursor = my_coll.find(query).await?;
while let Some(doc) = cursor.try_next().await? {
    println!("{}", doc);
}

{ "_id":{...},"theaterId":1908,"location":{"address":{...},"geo":{"type":"Point","coordinates":[-73.983487,40.76078] } } }
{ "_id":{...},"theaterId":1448,"location":{"address":{...},"geo":{"type":"Point","coordinates":[-73.982094,40.769882] } } }

let chicago = doc! {
    "type": "Polygon",
    "coordinates": vec![
        vec![
            vec![-87.851, 41.976],
            vec![-87.851, 41.653],
            vec![-87.651, 41.653],
            vec![-87.651, 41.976],
            vec![-87.851, 41.976],
        ]
    ]
};
let query = doc! {"location.geo":
    doc! { "$geoWithin": { "$geometry": chicago }}
};
let mut cursor = my_coll.find(query).await?;
while let Some(doc) = cursor.try_next().await? {
    println!("{}", doc);
}

{ "_id":{...},"theaterId":322,"location":{"address":{...},"geo":{ "type":"Point","coordinates":[-87.849403, 41.90707] } } }
{ "_id":{...},"theaterId":2960,"location":{"address":{...},"geo":{ "type":"Point","coordinates":[-87.811262, 41.847938] } } }
{ "_id":{...},"theaterId":323,"location":{"address":{...},"geo":{ "type":"Point","coordinates":[-87.653557, 41.912025] } } }
{ "_id":{...},"theaterId":320,"location":{"address":{...},"geo":{ "type":"Point","coordinates":[-87.805817, 41.847572] } } }
{ "_id":{...},"theaterId":814,"location":{"address":{...},"geo":{ "type":"Point","coordinates":[-87.670631, 41.919514] } } }

Additional Information

To learn more about find operations, see the Retrieve Data guide.

To learn more about working with geospatial data, see the following Server manual pages:

• Geospatial Data

• GeoJSON