Messtone Devices Enables multiple vehicles location {“alg”:”RS256″,”type”:”JWT”,”kid”:”private_key_id_of_consumer_service_account”}.{“iss”:”superuserrharper@messtonegcpproject.iam.gserviceaccount.com”,”sub”:”superuserrharper@messtonegcpproject.iam.gserviceaccount.com”,”aud”:”https://fleetengine.googleapis.com/&#8221;,”lat”:1511900000,”exp”:1511903600,”scope”:”https://www.googleapis.com/auth/xapi&#8221;,”authorization”:{“taskid”:”*”,”deliveryvehicleid”:”*”,}} create a a authentication token fetcher: JavaScript function authTokenFetcher(options){//options is a record containing two keys called //serviceType and context.The developer should //generate the correct SERVER_TOKEN_URL and request //based on the values of these fields.const response=await fetch(SERVER_TOKEN_URL);if(! response.ok){throw new Error(response.statusText);}const data=await response.json( );return{token:data.Token,expiresInSeconds:data.ExpiresInSeconds};}<script src=”https://maps.googleapis.com/maps/apis/js?key=MESSTONE_API_KEY&callback=initMap&libraries=journeySharing”defer></script>JavaScript locationProvider=new google.maps.journeySharing.FleetEngineDeliveryVehicleLocationProvider({projectId,authTokenFetcher,//Optionally,messtone may specify //deliveryVehicleId to immediately start //tracking.deliveryVehicleId: ‘messtone-delivery-id’,});