Routes Preferred API is currently available only to select customers. Contact sales to learn more.

Computing a Custom Route Examples

You can use the ComputeCustomRoutes method in an HTTP request and response or with any language that supports gRPC, including Java and Go.

HTTP examples

The following example demonstrates a sample curl request and response.

Request:

curl -X POST -d '{
  "origin":{
    "location":{
      "latLng":{
        "latitude":37.419734,
        "longitude":-122.0827784
      }
    }
  },
  "destination":{
    "location":{
      "latLng":{
        "latitude":37.417670,
        "longitude":-122.079595
      }
    }
  },
  "travelMode":"DRIVE",
  "routingPreference":"TRAFFIC_AWARE",
  "routeObjective": {
    "rateCard":{
      "costPerMinute":{
         "value":1.1
      },
      "costPerKm":{
         "value":2.2
      }
    }
  }
}' \
-H 'Content-Type: application/json' \
-H 'X-Goog-Api-Key: <YOUR_API_KEY>' \
-H 'X-Goog-FieldMask: routes.route.distanceMeters,routes.route.duration,routes.token,routes.route.travelAdvisory.tollInfo' \
'https://routespreferred.googleapis.com/v1alpha:computeCustomRoutes'

Response:

{
  "routes": [
    {
      "route": {
        "distanceMeters": 987,
        "duration": "247s",
        "travelAdvisory": {
          "tollInfo": {}
        }
      },
      "token": "CocCCnYKCNOX2XMIWqf2EihazE0WzZ87txlU4F74nQiWxZpgRgOzf3TMHUm1sVpY4APnvf_BWoEYGibs64nuCxYcsQEXqQjaChCLGOkBHNseoyoAmAG1CxbkG58hEhJ4FiIBKkIJbwqHAz2qAhZfSgivvZI-AACAP3gBEAQaigEKhwEKLAohChYIAxISCgcQARiAwtcvEgcQAhiAhK9fEQAAAAAAAPA_EareoBH6vShAEg4IABADEAYYAkIEGgIIBRoGCgQIAhACIj8KNjIwMjAtMDYtMTB8MTI6NTY6MzcuODg3OTEzLTA3fDEwLjk5LjE5OS4xNnwtMTA3Mjc4OTI3MhCHwajvnhs"
    }
  ]
}

The route token in the ComputeCustomRoutes response should be passed to the Navigation SDK to start a navigation session, which attempts to follow the route returned by the Routes Preferred API. Route tokens do not expire, but due to dynamic road conditions, routes generated with a given token may differ from the original route. We strongly recommend using the route token within minutes of token generation.

For more information on route tokens, see the Navigation SDK for Android and Navigation SDK for iOS documentation:

Java and Go examples

The following examples show how to call the ComputeCustomRoutes method with Java or Go. See the corresponding Java and Go Github repositories for build instructions.

Java

package com.example;

import com.google.maps.routes.v1.ComputeCustomRoutesRequest;
import com.google.maps.routes.v1.ComputeCustomRoutesResponse;
import com.google.maps.routes.v1.Location;
import com.google.maps.routes.v1.PolylineQuality;
import com.google.maps.routes.v1.RouteModifiers;
import com.google.maps.routes.v1.RouteObjective;
import com.google.maps.routes.v1.RouteObjective.RateCard;
import com.google.maps.routes.v1.RouteObjective.RateCard.MonetaryCost;
import com.google.maps.routes.v1.RouteTravelMode;
import com.google.maps.routes.v1.RoutingPreference;
import com.google.maps.routes.v1.Units;
import com.google.maps.routes.v1.Waypoint;
import com.google.maps.routes.v1alpha.RoutesAlphaGrpc;
import com.google.type.LatLng;
import io.grpc.CallOptions;
import io.grpc.Channel;
import io.grpc.ClientCall;
import io.grpc.ClientInterceptor;
import io.grpc.ClientInterceptors;
import io.grpc.ForwardingClientCall;
import io.grpc.Metadata;
import io.grpc.MethodDescriptor;
import io.grpc.StatusRuntimeException;
import io.grpc.netty.NettyChannelBuilder;
import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;

public class RoutesPreferredCustomRoutesClient {
  // For more detail on inserting API keys, see:
  // https://cloud.google.com/endpoints/docs/grpc/restricting-api-access-with-api-keys#java
  // For more detail on system parameters (such as FieldMask), see:
  // https://cloud.google.com/apis/docs/system-parameters
  private static final class RoutesPreferredInterceptor implements ClientInterceptor {
    private final String apiKey;
    private static final Logger logger =
        Logger.getLogger(RoutesPreferredInterceptor.class.getName());
    private static Metadata.Key<String> API_KEY_HEADER =
        Metadata.Key.of("x-goog-api-key", Metadata.ASCII_STRING_MARSHALLER);
    private static Metadata.Key<String> FIELD_MASK_HEADER =
        Metadata.Key.of("x-goog-fieldmask", Metadata.ASCII_STRING_MARSHALLER);

    public RoutesPreferredInterceptor(String apiKey) {
      this.apiKey = apiKey;
    }

    @Override
    public <ReqT, RespT> ClientCall<ReqT, RespT> interceptCall(
        MethodDescriptor<ReqT, RespT> method, CallOptions callOptions, Channel next) {
      logger.info("Intercepted " + method.getFullMethodName());
      ClientCall<ReqT, RespT> call = next.newCall(method, callOptions);
      call =
          new ForwardingClientCall.SimpleForwardingClientCall<ReqT, RespT>(call) {
            @Override
            public void start(Listener<RespT> responseListener, Metadata headers) {
              headers.put(API_KEY_HEADER, apiKey);
              // Note that setting the field mask to * is OK for testing, but discouraged in
              // production. For example, for ComputeCustomRoutes, set the field mask to
              // "routes.route.duration,routes.route.distanceMeters,routes.route.polyline"
              // in order to get the route distances, durations, and encoded polylines.
              headers.put(FIELD_MASK_HEADER, "*");
              super.start(responseListener, headers);
            }
          };
      return call;
    }
  }

  private static final Logger logger =
      Logger.getLogger(RoutesPreferredCustomRoutesClient.class.getName());
  private final RoutesAlphaGrpc.RoutesAlphaBlockingStub blockingStub;

  public RoutesPreferredCustomRoutesClient(Channel channel) {
    blockingStub = RoutesAlphaGrpc.newBlockingStub(channel);
  }

  public static Waypoint createWaypointForLatLng(double lat, double lng) {
    return Waypoint.newBuilder()
        .setLocation(
            Location.newBuilder().setLatLng(LatLng.newBuilder().setLatitude(lat).setLongitude(lng)))
        .build();
  }

  public void computeCustomRoutes() {
    ComputeCustomRoutesRequest request =
        ComputeCustomRoutesRequest.newBuilder()
            .setOrigin(createWaypointForLatLng(37.420761, -122.081356))
            .setDestination(createWaypointForLatLng(37.420999, -122.086894))
            .setRouteObjective(
                RouteObjective.newBuilder()
                    .setRateCard(
                        RateCard.newBuilder()
                            .setCostPerMinute(MonetaryCost.newBuilder().setValue(1.1))))
            .setTravelMode(RouteTravelMode.DRIVE)
            .setRoutingPreference(RoutingPreference.TRAFFIC_AWARE)
            .setUnits(Units.METRIC)
            .setLanguageCode("en-us")
            .setRouteModifiers(
                RouteModifiers.newBuilder()
                    .setAvoidTolls(false)
                    .setAvoidHighways(true)
                    .setAvoidFerries(true))
            .setPolylineQuality(PolylineQuality.OVERVIEW)
            .build();
    ComputeCustomRoutesResponse response;
    try {
      logger.info("About to send request: " + request.toString());
      response =
          blockingStub.withDeadlineAfter(2000, TimeUnit.MILLISECONDS).computeCustomRoutes(request);
    } catch (StatusRuntimeException e) {
      logger.log(Level.WARNING, "RPC failed: {0}", e.getStatus());
      return;
    }
    logger.info("Response: " + response.toString());
  }

  public static void main(String[] args) throws Exception {
    String apiKey = System.getenv("GOOGLE_MAPS_API_KEY");

    // The standard TLS port is 443
    Channel channel = NettyChannelBuilder.forAddress("routespreferred.googleapis.com", 443).build();
    channel = ClientInterceptors.intercept(channel, new RoutesPreferredInterceptor(apiKey));

    RoutesPreferredCustomRoutesClient client = new RoutesPreferredCustomRoutesClient(channel);
    client.computeCustomRoutes();
  }
}
  

Go

package main

import (
	"context"
	"crypto/tls"
	"log"
	"os"
	"time"

	"github.com/golang/protobuf/proto"
	v1 "google.golang.org/genproto/googleapis/maps/routes/v1"
	v1alpha "google.golang.org/genproto/googleapis/maps/routes/v1alpha"
	"google.golang.org/genproto/googleapis/type/latlng"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials"
	"google.golang.org/grpc/metadata"
)

const (
	serverAddr = "routespreferred.googleapis.com:443"
	// Note that setting the field mask to * is OK for testing, but discouraged in
	// production.
	// For example, for ComputeRoutes, set the field mask to
	// "routes.distanceMeters,routes.duration,routes.polyline.encodedPolyline"
	// in order to get the route distances, durations, and encoded polylines.
	fieldMask = "*"
)

func createWaypoint(lat float64, lng float64) *v1.Waypoint {
	return &v1.Waypoint{LocationType: &v1.Waypoint_Location{
		Location: &v1.Location{
			LatLng: &latlng.LatLng{Latitude: lat, Longitude: lng},
		},
	}}
}

func callComputeCustomRoutes(client v1alpha.RoutesAlphaClient, ctx *context.Context) {
	request := v1.ComputeCustomRoutesRequest{
		Origin:      createWaypoint(37.420761, -122.081356),
		Destination: createWaypoint(37.420999, -122.086894),
		RouteObjective: &v1.RouteObjective{
			Objective: &v1.RouteObjective_RateCard_{
				RateCard: &v1.RouteObjective_RateCard{
					CostPerMinute: &v1.RouteObjective_RateCard_MonetaryCost{Value: 1.1},
				},
			},
		},
		TravelMode:        v1.RouteTravelMode_DRIVE,
		RoutingPreference: v1.RoutingPreference_TRAFFIC_AWARE,
		Units:             v1.Units_METRIC,
		LanguageCode:      "en-us",
		RouteModifiers: &v1.RouteModifiers{
			AvoidTolls:    false,
			AvoidHighways: true,
			AvoidFerries:  true,
		},
		PolylineQuality: v1.PolylineQuality_OVERVIEW,
	}
	marshaler := proto.TextMarshaler{}
	log.Printf("Sending request: \n%s", marshaler.Text(&request))
	result, err := client.ComputeCustomRoutes(*ctx, &request)

	if err != nil {
		log.Fatalf("Failed to call ComputeCustomRoutes: %v", err)
	}
	log.Printf("Result: %s", marshaler.Text(result))
}

func main() {
	config := tls.Config{}
	conn, err := grpc.Dial(serverAddr,
		grpc.WithTransportCredentials(credentials.NewTLS(&config)))
	if err != nil {
		log.Fatalf("Failed to connect: %v", err)
	}
	defer conn.Close()
	client := v1alpha.NewRoutesAlphaClient(conn)
	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
	ctx = metadata.AppendToOutgoingContext(ctx, "X-Goog-Api-Key", os.Getenv("GOOGLE_MAPS_API_KEY"))
	ctx = metadata.AppendToOutgoingContext(ctx, "X-Goog-Fieldmask", fieldMask)
	defer cancel()

	callComputeCustomRoutes(client, &ctx)
}

  

Calculating toll fees examples

The following example uses the computeCustomRoutes method to return toll information on a route with an estimated price when a toll pass is used.

This feature is enabled with the routes.travelAdvisory.tollInfo field mask specified in the request. The toll pass is specified in the route_modifiers field. The toll price returned is based on the pricing used by the specified pass. If more than one pass is specified, the least expensive pricing is returned.

Request:

curl -X POST -d '{
  "origin":{
    "location":{
      "latLng":{
        "latitude":47.7020056,
        "longitude":-122.3479236
      }
    }
  },
  "destination":{
    "location":{
      "latLng":{
        "latitude":47.6192234,
        "longitude": -122.1676792
      }
    }
  },
  "travelMode":"DRIVE",
  "routingPreference": "TRAFFIC_AWARE_OPTIMAL",
  "routeModifiers":{
    "vehicleInfo":{
      "emissionType": "GASOLINE"
    },
    "tollPasses": "US_WA_GOOD_TO_GO"
  },
  "routeObjective":{
    "rateCard":{
      "costPerMinute":{
        "value":2
      },
      "costPerKm":{
        "value": 1
      },
      "includeTolls": true
    }
  }
}'\
-H 'Content-Type: application/json' \
-H 'X-Goog-Api-Key: <YOUR_API_KEY>' \
-H 'X-Goog-FieldMask: routes.route.duration,routes.route.distanceMeters,routes.route.travelAdvisory.tollInfo,routes.route.legs.travelAdvisory.tollInfo,fallbackInfo' \
'https://routespreferred.googleapis.com/v1alpha:computeCustomRoutes'

Response:

{
  "routes": [
    {
      "route": {
        "legs": [
          {
            "travelAdvisory": {
              "tollInfo": {
            "estimatedPrice": [
              {
                "currencyCode": "USD",
                "units": "2",
                "nanos": 700000000
              }
            ]
          }
        }
      }
    ],
    "distanceMeters": 22496,
    "duration": "1391s",
    "travelAdvisory": {
      "tollInfo": {
        "estimatedPrice": [
          {
            "currencyCode": "USD",
            "units": "2",
            "nanos": 700000000
          }
        ]
      }
    }
  ]
}

The following example uses the computeCustomRoutes method to return toll information on a route without price estimation.

This feature is also enabled with the routes.travelAdvisory.tollInfo field mask specified in the request. This is the expected behavior of the API if toll prices cannot be estimated at the time of the request. Generally, the presence of the tollInfo field in the response indicates that there is a toll on the route.

If you specify include_tolls in the routeObjective but Google does not have toll price information for the route, the response contains the fallback routeObjective FALLBACK_RATECARD_WITHOUT_TOLL_PRICE_DATA.

Request:

curl -X POST -d '{
  "origin":{
    "location":{
      "latLng":{
        "latitude":39.56227274,
        "longitude":15.12008516
      }
    }
  },
  "destination":{
    "location":{
      "latLng":{
        "latitude":39.56205718,
        "longitude": 15.12250773
      }
    }
  },
  "travelMode":"DRIVE",
  "routingPreference": "TRAFFIC_AWARE",
  "routeObjective":{
    "rateCard":{
      "costPerMinute":{
        "value":1
      },
      "costPerKm":{
        "value": 1
      },
      "includeTolls": true
    }
  }
}' \
-H 'Content-Type: application/json' \
-H 'X-Goog-Api-Key: <YOUR_API_KEY>' \
-H 'X-Goog-FieldMask: routes.route.duration,routes.route.distanceMeters,routes.route.travelAdvisory.tollInfo,routes.route.legs.travelAdvisory.tollInfo.estimatedPrice,fallbackInfo' \
'https://routespreferred.googleapis.com/v1alpha:computeCustomRoutes'

Response:

{
  "routes": [
    {
      "route": {
        "legs": [
          {
            "travelAdvisory": {
              "tollInfo": {}
            }
          }
        ],
        "distanceMeters": 101,
        "duration": "10s",
        "travelAdvisory": {
          "tollInfo": {}
        }
      }
    }
  ],
  "fallbackInfo": {
    "routeObjective": "FALLBACK_RATECARD_WITHOUT_TOLL_PRICE_DATA"
  }
}