This crates converts geojson strings to GeometryCollection.
This is the missing link between the geo-types crate and the geojson crate and should probably be part of geojson.
rust
let geojson_str = fs::read_to_string("src/tests/demo.json")?;
let collection: geo_types::GeometryCollection<f64> = geo_geojson::from_str(&geojson_str)?;