Module geojson::de

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Build your struct from GeoJSON using serde

To build instances of your struct from a GeoJSON String or reader, your type must implement or derive serde::Deserialize:

ⓘ
#[derive(serde::Deserialize)]
struct MyStruct {
    ...
}

Your type must have a field called geometry and it must be deserialized_with deserialize_geometry:

ⓘ
#[derive(serde::Deserialize)]
struct MyStruct {
   #[serde(deserialize_with = "geojson::de::deserialize_geometry")]
   geometry: geo_types::Point<f64>,
   ...
}

All fields in your struct other than geometry will be deserialized from the properties of the GeoJSON Feature.

Examples

use serde::Deserialize;
use geojson::de::deserialize_geometry;

#[derive(Deserialize)]
struct MyStruct {
    // Deserialize from geojson, rather than expecting the type's default serialization
    #[serde(deserialize_with = "deserialize_geometry")]
    geometry: geo_types::Point<f64>,
    name: String,
    population: u64
}

let input_geojson = serde_json::json!(
    {
        "type":"FeatureCollection",
        "features": [
            {
                "type": "Feature",
                "geometry": { "coordinates": [11.1,22.2], "type": "Point" },
                "properties": {
                    "name": "Downtown",
                    "population": 123
                }
            },
            {
                "type": "Feature",
                "geometry": { "coordinates": [33.3, 44.4], "type": "Point" },
                "properties": {
                    "name": "Uptown",
                    "population": 456
                }
            }
        ]
    }
).to_string();

let my_structs: Vec<MyStruct> = geojson::de::deserialize_feature_collection_str_to_vec(&input_geojson).unwrap();
assert_eq!("Downtown", my_structs[0].name);
assert_eq!(11.1, my_structs[0].geometry.x());

assert_eq!("Uptown", my_structs[1].name);
assert_eq!(33.3, my_structs[1].geometry.x());

Reading and Writing GeoJSON

This module is only concerned with reading in GeoJSON. If you’d also like to write GeoJSON output, you’ll want to combine this with the functionality from the crate::ser module:

ⓘ
#[derive(serde::Serialize, serde::Deserialize)]
struct MyStruct {
    // Serialize as geojson, rather than using the type's default serialization
    #[serde(serialize_with = "serialize_geometry", deserialize_with = "deserialize_geometry")]
    geometry: geo_types::Point<f64>,
    ...
}

Functions