google_maps

An unofficial Google Maps Platform client library for the Rust programming language.

This client currently implements the Directions API, Distance Matrix API, Elevation API, Geocoding API, Time Zone API, and parts of the Places and Roads API.

Installation

Configure the dependencies:

[dependencies]
google_maps = "3.5"

Optionally, add rust_decimal = "1" and rust_decimal_macros = "1" for access to the dec! macro. This macro can be used to define decimal numbers in your program.

This is useful for hard-coding latitudes and longitudes into your code for testing.

Feature Flags

The desired Google Maps APIs can be enabled individually via feature flags.

Additionally, usage of rustls for Reqwest is supported.

Google Maps Client Feature Flags:

• autocomplete
• directions
• distance_matrix
• elevation
• geocoding
• places
• roads
• time_zone
• enable-reqwest (uses reqwest for querying the Google Maps API).
• enable-reqwest-middleware (uses reqwest-middleware for querying the Google Maps API).
• geo (support for the geo crate's types)

Note: the autocomplete feature covers the Places API autocomplete-related services: Place Autocomplete requests and Query Autocomplete requests. All other Places API services are covered by the places feature.

reqwest Feature Flags

For use with enable-reqwest only.

• native-tls
• rustls
• gzip
• brotli

Default Feature Flags

By default, the Google Maps client includes all implemented Google Maps APIs. Reqwest will secure the connection using the system-native TLS (native-tls), and has gzip compression enabled (gzip).

default = [
	# Google Maps crate features:
	"directions",
	"distance_matrix",
	"elevation",
	"geocoding",
	"time_zone",
	"autocomplete",
	"roads",
	"places",

	# reqwest features:
	"enable-reqwest",
	"reqwest/default-tls",
	"reqwest/gzip",

	# rust_decimal features:
	"rust_decimal/serde",
]

Feature flag usage example

This example will only include the Google Maps Directions API. Reqwest will secure the connection using the Rustls library, and has brotli compression enabled.

google_maps = {
	version = "3.5",
	default-features = false,
	features = [
		"directions",
		"enable-reqwest",
		"rustls",
		"brotli"
	]
}

Release Notes

The full changelog is available here.

Releases are available on GitHub.

Examples

Directions API

The Directions API is a service that calculates directions between locations. You can search for directions for several modes of transportation, including transit, driving, walking, or cycling.

use google_maps::prelude::*;

let google_maps_client = GoogleMapsClient::new("YOUR_GOOGLE_API_KEY_HERE");

// Example request:

let directions = google_maps_client.directions(
    // Origin: Canadian Museum of Nature
    Location::from_address("240 McLeod St, Ottawa, ON K2P 2R1"),
    // Destination: Canada Science and Technology Museum
    Location::try_from_f32(45.403_509, -75.618_904)?,
)
.with_travel_mode(TravelMode::Driving)
.execute()
.await?;

// Dump entire response:

println!("{:#?}", directions);

Distance Matrix API

The Distance Matrix API is a service that provides travel distance and time for a matrix of origins and destinations, based on the recommended route between start and end points.

use google_maps::prelude::*;

let google_maps_client = GoogleMapsClient::new("YOUR_GOOGLE_API_KEY_HERE");

// Example request:

let distance_matrix = google_maps_client.distance_matrix(
    // Origins
    vec![
        // Microsoft
        Waypoint::from_address("One Microsoft Way, Redmond, WA 98052, United States"),
        // Cloudflare
        Waypoint::from_address("101 Townsend St, San Francisco, CA 94107, United States"),
    ],
    // Destinations
    vec![
        // Google
        Waypoint::from_place_id("ChIJj61dQgK6j4AR4GeTYWZsKWw"),
        // Mozilla
        Waypoint::try_from_f32(37.387_316, -122.060_008)?,
    ],
).execute().await?;

// Dump entire response:

println!("{:#?}", distance_matrix);

Elevation API (Positional)

The Elevation API provides elevation data for all locations on the surface of the earth, including depth locations on the ocean floor (which return negative values).

use google_maps::prelude::*;

let google_maps_client = GoogleMapsClient::new("YOUR_GOOGLE_API_KEY_HERE");

// Example request:

let elevation = google_maps_client.elevation()
    // Denver, Colorado, the "Mile High City"
    .for_positional_request(LatLng::try_from_dec(dec!(39.739_154), dec!(-104.984_703))?)
    .execute()
    .await?;

// Dump entire response:

println!("{:#?}", elevation);

// Display all results:

if let Some(results) = &elevation.results {
    for result in results {
        println!("Elevation: {} meters", result.elevation)
    }
}

Geocoding API

The Geocoding API is a service that provides geocoding and reverse geocoding of addresses. Geocoding is the process of converting addresses (like a street address) into geographic coordinates (like latitude and longitude), which you can use to place markers on a map, or position the map.

use google_maps::prelude::*;

let google_maps_client = GoogleMapsClient::new("YOUR_GOOGLE_API_KEY_HERE");

// Example request:

let location = google_maps_client.geocoding()
    .with_address("10 Downing Street London")
    .execute()
    .await?;

// Dump entire response:

println!("{:#?}", location);

// Print latitude & longitude coordinates:

for result in location.results {
    println!("{}", result.geometry.location)
}

Reverse Geocoding API

The Geocoding API is a service that provides geocoding and reverse geocoding of addresses. Reverse geocoding is the process of converting geographic coordinates into a human-readable address.

use google_maps::prelude::*;

let google_maps_client = GoogleMapsClient::new("YOUR_GOOGLE_API_KEY_HERE");

// Example request:

let location = google_maps_client.reverse_geocoding(
    // 10 Downing St, Westminster, London
    LatLng::try_from_dec(dec!(51.503_364), dec!(-0.127_625))?,
)
.with_result_type(PlaceType::StreetAddress)
.execute()
.await?;

// Dump entire response:

println!("{:#?}", location);

// Display all results:

for result in location.results {
    println!(
        "{}",
        result.address_components.iter()
            .map(|address_component| address_component.short_name.to_string())
            .collect::<Vec<String>>()
            .join(", ")
    );
}

Time Zone API

The Time Zone API provides time offset data for locations on the surface of the earth. You request the time zone information for a specific latitude/longitude pair and date. The API returns the name of that time zone, the time offset from UTC, and the daylight savings offset.

use google_maps::prelude::*;

let google_maps_client = GoogleMapsClient::new("YOUR_GOOGLE_API_KEY_HERE");

// Example request:

let time_zone = google_maps_client.time_zone(
     // St. Vitus Cathedral in Prague, Czechia
     LatLng::try_from_dec(dec!(50.090_903), dec!(14.400_512))?,
     // The time right now in UTC (Coordinated Universal Time)
     Utc::now()
).execute().await?;

// Dump entire response:

println!("{:#?}", time_zone);

// Usage example:

println!("Time at your computer: {}", Local::now().to_rfc2822());

if let Some(time_zone_id) = time_zone.time_zone_id {
    println!(
    	"Time in {}: {}",
        time_zone_id.name(),
        Utc::now().with_timezone(&time_zone_id).to_rfc2822()
    );
}

Geolocation API

Google's Geolocation API seems to be offline. While the online documentation is still available and the API appears configurable through the Google Cloud Platform console, the Geolocation API responds Status code 404 Not Found with an empty body to all requests. This API cannot be implemented until the server responds as expected.

Controlling Request Settings

The Google Maps client settings can be used to change the request rate and automatic retry parameters.

use google_maps::prelude::*;

let google_maps_client = GoogleMapsClient::new("YOUR_GOOGLE_API_KEY_HERE")
    // For all Google Maps Platform APIs, the client will limit 2 sucessful
    // requests for every 10 seconds:
    .with_rate(Api::All, 2, std::time::Duration::from_secs(10))
    // Returns the `GoogleMapsClient` struct to the caller. This struct is used
    // to make Google Maps Platform requests.
    .build();

Feedback

I would like for you to be successful with your project! If this crate is not working for you, doesn't work how you think it should, or if you have requests, or suggestions - please report them to me! I'm not always fast at responding but I will respond. Thanks!

Roadmap

• Track both requests and request elements for rate limiting.
• Make a generic get() function for that can be used by all APIs.
• Convert explicit query validation to session types wherever reasonable.
• Places API. Only partly implemented. If you would like to have any missing pieces implemented, please contact me.
• Roads API. Only partly implemented. If you would like to have any missing pieces implemented, please contact me.

Author's Note

This crate is expected to work well and have the more important Google Maps features implemented. It should work well because serde and, by default, reqwest do most of the heavy lifting!

I created this client library because I needed several Google Maps Platform features for a project that I'm working on. So, I've decided to spin my library off into a public crate. This is a very small token of gratitude and an attempt to give back to the Rust community. I hope it saves someone out there some work.