trip.avdl

@namespace("v0.1-example")

/*
 * Example protocol definition for a fitness or hiking app where you that
 * allows you to record the start and end of your trip.
 * Exercise: Add a new file 'waypoint.avdl' that models annotating places
 * along the way.
 */
protocol Trip {

    enum TripType {
        Hiking,
        Biking
    } = Hiking;

    enum GeomType {
        Point,
        Polygon
    } = Point;

    /** Trip start message. */
    record TripStart {
        /** 'trip_start' */
        string name;

        /** Timestamp in ISO 8601 format, UTC */
        string timestamp;

        /*  Could also be: Milliseconds since unix epoch, UTC. */
        /* timestamp_ms timestamp; */

        /** Trip ID, .e.g '06.1.2024'. */
        string trip_id;

        /** Hiking or biking? */
        TripType trip_type;

        /** Number of travellers */
        int num_travellers;

        /** Location where you started. geoJSON geometry type. Typically a
         *  Point but could also be a Polygon. */
        GeomType coord_type;

        /** geoJSON geometry coordinates, 1 element for Point, at least 4
         * points for Polygon. */
        array<array<double>> coordinates;
    }

    /** Trip end message. */
    record TripEnd {
        /** 'trip_end' */
        string name;

        /** Timestamp in ISO 8601 format, UTC */
        string timestamp;

        /** Trip ID, .e.g '06.1.2024'. */
        string trip_id;
    }
}