Remove renfe RT proxying, add Xunta feed, update script

1 files changed, 0 insertions, 1259 deletions

diff --git a/proxy_rt_renfe/gtfsrt.proto b/proxy_rt_renfe/gtfsrt.proto
deleted file mode 100644
index e050fc1..0000000
--- a/proxy_rt_renfe/gtfsrt.proto
+++ /dev/null
@@ -1,1259 +0,0 @@
-// Copyright 2015 The GTFS Specifications Authors.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Protocol definition file for GTFS Realtime.
-//
-// GTFS Realtime lets transit agencies provide consumers with realtime
-// information about disruptions to their service (stations closed, lines not
-// operating, important delays etc), location of their vehicles and expected
-// arrival times.
-//
-// This protocol is published at:
-// https://github.com/google/transit/tree/master/gtfs-realtime
-
-syntax = "proto2";
-option java_package = "com.google.transit.realtime";
-package transit_realtime;
-
-// The contents of a feed message.
-// A feed is a continuous stream of feed messages. Each message in the stream is
-// obtained as a response to an appropriate HTTP GET request.
-// A realtime feed is always defined with relation to an existing GTFS feed.
-// All the entity ids are resolved with respect to the GTFS feed.
-// Note that "required" and "optional" as stated in this file refer to Protocol
-// Buffer cardinality, not semantic cardinality.  See reference.md at
-// https://github.com/google/transit/tree/master/gtfs-realtime for field
-// semantic cardinality.
-message FeedMessage {
-  // Metadata about this feed and feed message.
-  required FeedHeader header = 1;
-
-  // Contents of the feed.
-  repeated FeedEntity entity = 2;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// Metadata about a feed, included in feed messages.
-message FeedHeader {
-  // Version of the feed specification.
-  // The current version is 2.0.  Valid versions are "2.0", "1.0".
-  required string gtfs_realtime_version = 1;
-
-  // Determines whether the current fetch is incremental.  Currently,
-  // DIFFERENTIAL mode is unsupported and behavior is unspecified for feeds
-  // that use this mode.  There are discussions on the GTFS Realtime mailing
-  // list around fully specifying the behavior of DIFFERENTIAL mode and the
-  // documentation will be updated when those discussions are finalized.
-  enum Incrementality {
-    FULL_DATASET = 0;
-    DIFFERENTIAL = 1;
-  }
-  optional Incrementality incrementality = 2 [default = FULL_DATASET];
-
-  // This timestamp identifies the moment when the content of this feed has been
-  // created (in server time). In POSIX time (i.e., number of seconds since
-  // January 1st 1970 00:00:00 UTC).
-  optional uint64 timestamp = 3;
-
-  // String that matches the feed_info.feed_version from the GTFS feed that the real
-  // time data is based on. Consumers can use this to identify which GTFS feed is
-  // currently active or when a new one is available to download.
-  optional string feed_version = 4;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// A definition (or update) of an entity in the transit feed.
-message FeedEntity {
-  // The ids are used only to provide incrementality support. The id should be
-  // unique within a FeedMessage. Consequent FeedMessages may contain
-  // FeedEntities with the same id. In case of a DIFFERENTIAL update the new
-  // FeedEntity with some id will replace the old FeedEntity with the same id
-  // (or delete it - see is_deleted below).
-  // The actual GTFS entities (e.g. stations, routes, trips) referenced by the
-  // feed must be specified by explicit selectors (see EntitySelector below for
-  // more info).
-  required string id = 1;
-
-  // Whether this entity is to be deleted. Relevant only for incremental
-  // fetches.
-  optional bool is_deleted = 2 [default = false];
-
-  // Data about the entity itself. Exactly one of the following fields must be
-  // present (unless the entity is being deleted).
-  optional TripUpdate trip_update = 3;
-  optional VehiclePosition vehicle = 4;
-  optional Alert alert = 5;
-
-  // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional Shape shape = 6;
-  optional Stop stop = 7;
-  optional TripModifications trip_modifications = 8;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-//
-// Entities used in the feed.
-//
-
-// Realtime update of the progress of a vehicle along a trip.
-// Depending on the value of ScheduleRelationship, a TripUpdate can specify:
-// - A trip that proceeds along the schedule.
-// - A trip that proceeds along a route but has no fixed schedule.
-// - A trip that have been added or removed with regard to schedule.
-//
-// The updates can be for future, predicted arrival/departure events, or for
-// past events that already occurred.
-// Normally, updates should get more precise and more certain (see
-// uncertainty below) as the events gets closer to current time.
-// Even if that is not possible, the information for past events should be
-// precise and certain. In particular, if an update points to time in the past
-// but its update's uncertainty is not 0, the client should conclude that the
-// update is a (wrong) prediction and that the trip has not completed yet.
-//
-// Note that the update can describe a trip that is already completed.
-// To this end, it is enough to provide an update for the last stop of the trip.
-// If the time of that is in the past, the client will conclude from that that
-// the whole trip is in the past (it is possible, although inconsequential, to
-// also provide updates for preceding stops).
-// This option is most relevant for a trip that has completed ahead of schedule,
-// but according to the schedule, the trip is still proceeding at the current
-// time. Removing the updates for this trip could make the client assume
-// that the trip is still proceeding.
-// Note that the feed provider is allowed, but not required, to purge past
-// updates - this is one case where this would be practically useful.
-message TripUpdate {
-  // The Trip that this message applies to. There can be at most one
-  // TripUpdate entity for each actual trip instance.
-  // If there is none, that means there is no prediction information available.
-  // It does *not* mean that the trip is progressing according to schedule.
-  required TripDescriptor trip = 1;
-
-  // Additional information on the vehicle that is serving this trip.
-  optional VehicleDescriptor vehicle = 3;
-
-  // Timing information for a single predicted event (either arrival or
-  // departure).
-  // Timing consists of delay and/or estimated time, and uncertainty.
-  // - delay should be used when the prediction is given relative to some
-  //   existing schedule in GTFS.
-  // - time should be given whether there is a predicted schedule or not. If
-  //   both time and delay are specified, time will take precedence
-  //   (although normally, time, if given for a scheduled trip, should be
-  //   equal to scheduled time in GTFS + delay).
-  //
-  // Uncertainty applies equally to both time and delay.
-  // The uncertainty roughly specifies the expected error in true delay (but
-  // note, we don't yet define its precise statistical meaning). It's possible
-  // for the uncertainty to be 0, for example for trains that are driven under
-  // computer timing control.
-  message StopTimeEvent {
-    // Delay (in seconds) can be positive (meaning that the vehicle is late) or
-    // negative (meaning that the vehicle is ahead of schedule). Delay of 0
-    // means that the vehicle is exactly on time.
-    optional int32 delay = 1;
-
-    // Event as absolute time.
-    // In Unix time (i.e., number of seconds since January 1st 1970 00:00:00
-    // UTC).
-    optional int64 time = 2;
-
-    // If uncertainty is omitted, it is interpreted as unknown.
-    // If the prediction is unknown or too uncertain, the delay (or time) field
-    // should be empty. In such case, the uncertainty field is ignored.
-    // To specify a completely certain prediction, set its uncertainty to 0.
-    optional int32 uncertainty = 3;
-
-    // Scheduled time for a NEW, REPLACEMENT, or DUPLICATED trip.
-    // In Unix time (i.e., number of seconds since January 1st 1970 00:00:00
-    // UTC).
-    // Optional if TripUpdate.schedule_relationship is NEW, REPLACEMENT or DUPLICATED, forbidden otherwise.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional int64 scheduled_time = 4;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features
-    // and modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-
-  // Realtime update for arrival and/or departure events for a given stop on a
-  // trip. Updates can be supplied for both past and future events.
-  // The producer is allowed, although not required, to drop past events.
-  message StopTimeUpdate {
-    // The update is linked to a specific stop either through stop_sequence or
-    // stop_id, so one of the fields below must necessarily be set.
-    // See the documentation in TripDescriptor for more information.
-
-    // Must be the same as in stop_times.txt in the corresponding GTFS feed.
-    optional uint32 stop_sequence = 1;
-    // Must be the same as in stops.txt in the corresponding GTFS feed.
-    optional string stop_id = 4;
-
-    optional StopTimeEvent arrival = 2;
-    optional StopTimeEvent departure = 3;
-
-    // Expected occupancy after departure from the given stop.
-    // Should be provided only for future stops.
-    // In order to provide departure_occupancy_status without either arrival or
-    // departure StopTimeEvents, ScheduleRelationship should be set to NO_DATA. 
-    optional VehiclePosition.OccupancyStatus departure_occupancy_status = 7;
-
-    // The relation between the StopTimeEvents and the static schedule.
-    enum ScheduleRelationship {
-      // The vehicle is proceeding in accordance with its static schedule of
-      // stops, although not necessarily according to the times of the schedule.
-      // At least one of arrival and departure must be provided. If the schedule
-      // for this stop contains both arrival and departure times then so must
-      // this update. Frequency-based trips (GTFS frequencies.txt with exact_times = 0)
-      // should not have a SCHEDULED value and should use UNSCHEDULED instead.
-      SCHEDULED = 0;
-
-      // The stop is skipped, i.e., the vehicle will not stop at this stop.
-      // Arrival and departure are optional.
-      SKIPPED = 1;
-
-      // No StopTimeEvents are given for this stop.
-      // The main intention for this value is to give time predictions only for
-      // part of a trip, i.e., if the last update for a trip has a NO_DATA
-      // specifier, then StopTimeEvents for the rest of the stops in the trip
-      // are considered to be unspecified as well.
-      // Neither arrival nor departure should be supplied.
-      NO_DATA = 2;
-
-      // The vehicle is operating a trip defined in GTFS frequencies.txt with exact_times = 0.
-      // This value should not be used for trips that are not defined in GTFS frequencies.txt,
-      // or trips in GTFS frequencies.txt with exact_times = 1. Trips containing StopTimeUpdates
-      // with ScheduleRelationship=UNSCHEDULED must also set TripDescriptor.ScheduleRelationship=UNSCHEDULED.
-      // NOTE: This field is still experimental, and subject to change. It may be
-      // formally adopted in the future.
-      UNSCHEDULED = 3;
-    }
-    optional ScheduleRelationship schedule_relationship = 5
-    [default = SCHEDULED];
-
-    // Provides the updated values for the stop time.
-    // NOTE: This message is still experimental, and subject to change. It may be formally adopted in the future.
-    message StopTimeProperties {
-      // Supports real-time stop assignments. Refers to a stop_id defined in the GTFS stops.txt.
-      // The new assigned_stop_id should not result in a significantly different trip experience for the end user than
-      // the stop_id defined in GTFS stop_times.txt. In other words, the end user should not view this new stop_id as an
-      // "unusual change" if the new stop was presented within an app without any additional context.
-      // For example, this field is intended to be used for platform assignments by using a stop_id that belongs to the
-      // same station as the stop originally defined in GTFS stop_times.txt.
-      // To assign a stop without providing any real-time arrival or departure predictions, populate this field and set
-      // StopTimeUpdate.schedule_relationship = NO_DATA.
-      // If this field is populated, it is preferred to omit `StopTimeUpdate.stop_id` and use only `StopTimeUpdate.stop_sequence`. If
-      // `StopTimeProperties.assigned_stop_id` and `StopTimeUpdate.stop_id` are populated, `StopTimeUpdate.stop_id` must match `assigned_stop_id`.
-      // Platform assignments should be reflected in other GTFS-realtime fields as well
-      // (e.g., `VehiclePosition.stop_id`).
-      // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-      optional string assigned_stop_id = 1;
-
-      // The updated headsign of the vehicle at the stop.
-      // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-      optional string stop_headsign = 2;
-      
-      enum DropOffPickupType {
-        // Regularly scheduled pickup/dropoff.
-        REGULAR = 0;
-
-        // No pickup/dropoff available
-        NONE = 1;
-
-        // Must phone agency to arrange pickup/dropoff.
-        PHONE_AGENCY = 2;
-
-        // Must coordinate with driver to arrange pickup/dropoff.
-        COORDINATE_WITH_DRIVER = 3;
-      }
-      
-      // The updated pickup of the vehicle at the stop.
-      // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-      optional DropOffPickupType pickup_type = 3;
-
-      // The updated drop off of the vehicle at the stop.
-      // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-      optional DropOffPickupType drop_off_type = 4;
-
-      // The extensions namespace allows 3rd-party developers to extend the
-      // GTFS Realtime Specification in order to add and evaluate new features
-      // and modifications to the spec.
-      extensions 1000 to 1999;
-
-      // The following extension IDs are reserved for private use by any organization.
-      extensions 9000 to 9999;
-    }
-
-    // Realtime updates for certain properties defined within GTFS stop_times.txt
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional StopTimeProperties stop_time_properties = 6;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features
-    // and modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-
-  // Updates to StopTimes for the trip (both future, i.e., predictions, and in
-  // some cases, past ones, i.e., those that already happened).
-  // The updates must be sorted by stop_sequence, and apply for all the
-  // following stops of the trip up to the next specified one.
-  //
-  // Example 1:
-  // For a trip with 20 stops, a StopTimeUpdate with arrival delay and departure
-  // delay of 0 for stop_sequence of the current stop means that the trip is
-  // exactly on time.
-  //
-  // Example 2:
-  // For the same trip instance, 3 StopTimeUpdates are provided:
-  // - delay of 5 min for stop_sequence 3
-  // - delay of 1 min for stop_sequence 8
-  // - delay of unspecified duration for stop_sequence 10
-  // This will be interpreted as:
-  // - stop_sequences 3,4,5,6,7 have delay of 5 min.
-  // - stop_sequences 8,9 have delay of 1 min.
-  // - stop_sequences 10,... have unknown delay.
-  repeated StopTimeUpdate stop_time_update = 2;
-
-  // The most recent moment at which the vehicle's real-time progress was measured
-  // to estimate StopTimes in the future. When StopTimes in the past are provided,
-  // arrival/departure times may be earlier than this value. In POSIX
-  // time (i.e., the number of seconds since January 1st 1970 00:00:00 UTC).
-  optional uint64 timestamp = 4;
-
-  // The current schedule deviation for the trip.  Delay should only be
-  // specified when the prediction is given relative to some existing schedule
-  // in GTFS.
-  //
-  // Delay (in seconds) can be positive (meaning that the vehicle is late) or
-  // negative (meaning that the vehicle is ahead of schedule). Delay of 0
-  // means that the vehicle is exactly on time.
-  //
-  // Delay information in StopTimeUpdates take precedent of trip-level delay
-  // information, such that trip-level delay is only propagated until the next
-  // stop along the trip with a StopTimeUpdate delay value specified.
-  //
-  // Feed providers are strongly encouraged to provide a TripUpdate.timestamp
-  // value indicating when the delay value was last updated, in order to
-  // evaluate the freshness of the data.
-  //
-  // NOTE: This field is still experimental, and subject to change. It may be
-  // formally adopted in the future.
-  optional int32 delay = 5;
-
-  // Defines updated properties of the trip, such as a new shape_id when there is a detour. Or defines the
-  // trip_id, start_date, and start_time of a DUPLICATED trip. 
-  // NOTE: This message is still experimental, and subject to change. It may be formally adopted in the future.
-  message TripProperties {
-    // Defines the identifier of a new trip that is a duplicate of an existing trip defined in (CSV) GTFS trips.txt
-    // but will start at a different service date and/or time (defined using the TripProperties.start_date and
-    // TripProperties.start_time fields). See definition of trips.trip_id in (CSV) GTFS. Its value must be different
-    // than the ones used in the (CSV) GTFS. Required if schedule_relationship=DUPLICATED, otherwise this field must not
-    // be populated and will be ignored by consumers.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional string trip_id = 1;
-    // Service date on which the DUPLICATED trip will be run, in YYYYMMDD format. Required if
-    // schedule_relationship=DUPLICATED, otherwise this field must not be populated and will be ignored by consumers.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional string start_date = 2;
-    // Defines the departure start time of the trip when it’s duplicated. See definition of stop_times.departure_time
-    // in (CSV) GTFS. Scheduled arrival and departure times for the duplicated trip are calculated based on the offset
-    // between the original trip departure_time and this field. For example, if a GTFS trip has stop A with a
-    // departure_time of 10:00:00 and stop B with departure_time of 10:01:00, and this field is populated with the value
-    // of 10:30:00, stop B on the duplicated trip will have a scheduled departure_time of 10:31:00. Real-time prediction
-    // delay values are applied to this calculated schedule time to determine the predicted time. For example, if a
-    // departure delay of 30 is provided for stop B, then the predicted departure time is 10:31:30. Real-time
-    // prediction time values do not have any offset applied to them and indicate the predicted time as provided.
-    // For example, if a departure time representing 10:31:30 is provided for stop B, then the predicted departure time
-    // is 10:31:30. This field is required if schedule_relationship is DUPLICATED, otherwise this field must not be
-    // populated and will be ignored by consumers.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional string start_time = 3;
-    // Specifies the identifier of the shape of the vehicle travel path when the trip shape differs from the shape specified in (CSV) GTFS
-    // or to specify it in real-time when it's not provided by (CSV) GTFS, such as a vehicle that takes differing paths based on rider demand. See definition of trips.shape_id in (CSV) GTFS.
-    // If a shape is neither defined in (CSV) GTFS nor in real-time, the shape is considered unknown. This field can refer to a shape defined in the (CSV) GTFS in shapes.txt or a `Shape` in the same (protobuf) real-time feed. 
-    // The order of stops (stop sequences) for this trip must remain the same as (CSV) GTFS. 
-    // If it refers to a `Shape` entity in the same real-time feed, the value of this field should be the one of the `shape_id` inside the entity, and _not_ the `id` of `FeedEntity`.
-    // Stops that are a part of the original trip but will no longer be made, such as when a detour occurs, should be marked as schedule_relationship=SKIPPED or more details can be provided via a `TripModifications` message.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future. 
-    optional string shape_id = 4;
-
-    // Specifies the headsign for this trip when it differs from the original.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional string trip_headsign = 5;
-
-    // Specifies the name for this trip when it differs from the original.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional string trip_short_name = 6;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features
-    // and modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-  optional TripProperties trip_properties = 6;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// Realtime positioning information for a given vehicle.
-message VehiclePosition {
-  // The Trip that this vehicle is serving.
-  // Can be empty or partial if the vehicle can not be identified with a given
-  // trip instance.
-  optional TripDescriptor trip = 1;
-
-  // Additional information on the vehicle that is serving this trip.
-  optional VehicleDescriptor vehicle = 8;
-
-  // Current position of this vehicle.
-  optional Position position = 2;
-
-  // The stop sequence index of the current stop. The meaning of
-  // current_stop_sequence (i.e., the stop that it refers to) is determined by
-  // current_status.
-  // If current_status is missing IN_TRANSIT_TO is assumed.
-  optional uint32 current_stop_sequence = 3;
-  // Identifies the current stop. The value must be the same as in stops.txt in
-  // the corresponding GTFS feed.
-  optional string stop_id = 7;
-
-  enum VehicleStopStatus {
-    // The vehicle is just about to arrive at the stop (on a stop
-    // display, the vehicle symbol typically flashes).
-    INCOMING_AT = 0;
-
-    // The vehicle is standing at the stop.
-    STOPPED_AT = 1;
-
-    // The vehicle has departed and is in transit to the next stop.
-    IN_TRANSIT_TO = 2;
-  }
-  // The exact status of the vehicle with respect to the current stop.
-  // Ignored if current_stop_sequence is missing.
-  optional VehicleStopStatus current_status = 4 [default = IN_TRANSIT_TO];
-
-  // Moment at which the vehicle's position was measured. In POSIX time
-  // (i.e., number of seconds since January 1st 1970 00:00:00 UTC).
-  optional uint64 timestamp = 5;
-
-  // Congestion level that is affecting this vehicle.
-  enum CongestionLevel {
-    UNKNOWN_CONGESTION_LEVEL = 0;
-    RUNNING_SMOOTHLY = 1;
-    STOP_AND_GO = 2;
-    CONGESTION = 3;
-    SEVERE_CONGESTION = 4;  // People leaving their cars.
-  }
-  optional CongestionLevel congestion_level = 6;
-
-  // The state of passenger occupancy for the vehicle or carriage.
-  // Individual producers may not publish all OccupancyStatus values. Therefore, consumers
-  // must not assume that the OccupancyStatus values follow a linear scale.
-  // Consumers should represent OccupancyStatus values as the state indicated 
-  // and intended by the producer. Likewise, producers must use OccupancyStatus values that
-  // correspond to actual vehicle occupancy states.
-  // For describing passenger occupancy levels on a linear scale, see `occupancy_percentage`.
-  // This field is still experimental, and subject to change. It may be formally adopted in the future.
-  enum OccupancyStatus {
-    // The vehicle or carriage is considered empty by most measures, and has few or no
-    // passengers onboard, but is still accepting passengers.
-    EMPTY = 0;
-
-    // The vehicle or carriage has a large number of seats available.
-    // The amount of free seats out of the total seats available to be
-    // considered large enough to fall into this category is determined at the
-    // discretion of the producer.
-    MANY_SEATS_AVAILABLE = 1;
-
-    // The vehicle or carriage has a relatively small number of seats available.
-    // The amount of free seats out of the total seats available to be
-    // considered small enough to fall into this category is determined at the
-    // discretion of the feed producer.
-    FEW_SEATS_AVAILABLE = 2;
-
-    // The vehicle or carriage can currently accommodate only standing passengers.
-    STANDING_ROOM_ONLY = 3;
-
-    // The vehicle or carriage can currently accommodate only standing passengers
-    // and has limited space for them.
-    CRUSHED_STANDING_ROOM_ONLY = 4;
-
-    // The vehicle or carriage is considered full by most measures, but may still be
-    // allowing passengers to board.
-    FULL = 5;
-
-    // The vehicle or carriage is not accepting passengers, but usually accepts passengers for boarding.
-    NOT_ACCEPTING_PASSENGERS = 6;
-
-    // The vehicle or carriage doesn't have any occupancy data available at that time.
-    NO_DATA_AVAILABLE = 7;
-
-    // The vehicle or carriage is not boardable and never accepts passengers.
-    // Useful for special vehicles or carriages (engine, maintenance carriage, etc…).
-    NOT_BOARDABLE = 8;
-
-  }
-  // If multi_carriage_status is populated with per-carriage OccupancyStatus,
-  // then this field should describe the entire vehicle with all carriages accepting passengers considered.
-  optional OccupancyStatus occupancy_status = 9;
-
-  // A percentage value indicating the degree of passenger occupancy in the vehicle.
-  // The values are represented as an integer without decimals. 0 means 0% and 100 means 100%.
-  // The value 100 should represent the total maximum occupancy the vehicle was designed for,
-  // including both seated and standing capacity, and current operating regulations allow.
-  // The value may exceed 100 if there are more passengers than the maximum designed capacity.
-  // The precision of occupancy_percentage should be low enough that individual passengers cannot be tracked boarding or alighting the vehicle.
-  // If multi_carriage_status is populated with per-carriage occupancy_percentage, 
-  // then this field should describe the entire vehicle with all carriages accepting passengers considered.
-  // This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional uint32 occupancy_percentage = 10;
-
-  // Carriage specific details, used for vehicles composed of several carriages
-  // This message/field is still experimental, and subject to change. It may be formally adopted in the future.
-  message CarriageDetails {
-
-    // Identification of the carriage. Should be unique per vehicle.
-    optional string id = 1;
-
-    // User visible label that may be shown to the passenger to help identify
-    // the carriage. Example: "7712", "Car ABC-32", etc...
-    // This message/field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional string label = 2;
-
-    // Occupancy status for this given carriage, in this vehicle
-    // This message/field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional OccupancyStatus occupancy_status = 3 [default = NO_DATA_AVAILABLE];
-
-    // Occupancy percentage for this given carriage, in this vehicle.
-    // Follows the same rules as "VehiclePosition.occupancy_percentage"
-    // -1 in case data is not available for this given carriage (as protobuf defaults to 0 otherwise)
-    // This message/field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional int32 occupancy_percentage = 4 [default = -1];
-
-    // Identifies the order of this carriage with respect to the other
-    // carriages in the vehicle's list of CarriageDetails.
-    // The first carriage in the direction of travel must have a value of 1.
-    // The second value corresponds to the second carriage in the direction
-    // of travel and must have a value of 2, and so forth.
-    // For example, the first carriage in the direction of travel has a value of 1.
-    // If the second carriage in the direction of travel has a value of 3,
-    // consumers will discard data for all carriages (i.e., the multi_carriage_details field).
-    // Carriages without data must be represented with a valid carriage_sequence number and the fields 
-    // without data should be omitted (alternately, those fields could also be included and set to the "no data" values).
-    // This message/field is still experimental, and subject to change. It may be formally adopted in the future.
-    optional uint32 carriage_sequence = 5;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features and
-    // modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-
-  // Details of the multiple carriages of this given vehicle.
-  // The first occurrence represents the first carriage of the vehicle, 
-  // given the current direction of travel. 
-  // The number of occurrences of the multi_carriage_details 
-  // field represents the number of carriages of the vehicle.
-  // It also includes non boardable carriages, 
-  // like engines, maintenance carriages, etc… as they provide valuable 
-  // information to passengers about where to stand on a platform.
-  // This message/field is still experimental, and subject to change. It may be formally adopted in the future.
-  repeated CarriageDetails multi_carriage_details = 11;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// An alert, indicating some sort of incident in the public transit network.
-message Alert {
-  // Time when the alert should be shown to the user. If missing, the
-  // alert will be shown as long as it appears in the feed.
-  // If multiple ranges are given, the alert will be shown during all of them.
-  repeated TimeRange active_period = 1;
-
-  // Entities whose users we should notify of this alert.
-  repeated EntitySelector informed_entity = 5;
-
-  // Cause of this alert. If cause_detail is included, then Cause must also be included.
-  enum Cause {
-    UNKNOWN_CAUSE = 1;
-    OTHER_CAUSE = 2;        // Not machine-representable.
-    TECHNICAL_PROBLEM = 3;
-    STRIKE = 4;             // Public transit agency employees stopped working.
-    DEMONSTRATION = 5;      // People are blocking the streets.
-    ACCIDENT = 6;
-    HOLIDAY = 7;
-    WEATHER = 8;
-    MAINTENANCE = 9;
-    CONSTRUCTION = 10;
-    POLICE_ACTIVITY = 11;
-    MEDICAL_EMERGENCY = 12;
-  }
-  optional Cause cause = 6 [default = UNKNOWN_CAUSE];
-
-  // What is the effect of this problem on the affected entity. If effect_detail is included, then Effect must also be included.
-  enum Effect {
-    NO_SERVICE = 1;
-    REDUCED_SERVICE = 2;
-
-    // We don't care about INsignificant delays: they are hard to detect, have
-    // little impact on the user, and would clutter the results as they are too
-    // frequent.
-    SIGNIFICANT_DELAYS = 3;
-
-    DETOUR = 4;
-    ADDITIONAL_SERVICE = 5;
-    MODIFIED_SERVICE = 6;
-    OTHER_EFFECT = 7;
-    UNKNOWN_EFFECT = 8;
-    STOP_MOVED = 9;
-    NO_EFFECT = 10;
-    ACCESSIBILITY_ISSUE = 11;
-  }
-  optional Effect effect = 7 [default = UNKNOWN_EFFECT];
-
-  // The URL which provides additional information about the alert.
-  optional TranslatedString url = 8;
-
-  // Alert header. Contains a short summary of the alert text as plain-text.
-  optional TranslatedString header_text = 10;
-
-  // Full description for the alert as plain-text. The information in the
-  // description should add to the information of the header.
-  optional TranslatedString description_text = 11;
-
-  // Text for alert header to be used in text-to-speech implementations. This field is the text-to-speech version of header_text.
-  optional TranslatedString tts_header_text = 12;
-
-  // Text for full description for the alert to be used in text-to-speech implementations. This field is the text-to-speech version of description_text.
-  optional TranslatedString tts_description_text = 13;
-
-  // Severity of this alert.
-  enum SeverityLevel {
-    UNKNOWN_SEVERITY = 1;
-    INFO = 2;
-    WARNING = 3;
-    SEVERE = 4;
-  }
-
-  optional SeverityLevel severity_level = 14 [default = UNKNOWN_SEVERITY];
-
-  // TranslatedImage to be displayed along the alert text. Used to explain visually the alert effect of a detour, station closure, etc. The image must enhance the understanding of the alert. Any essential information communicated within the image must also be contained in the alert text.
-  // The following types of images are discouraged : image containing mainly text, marketing or branded images that add no additional information. 
-  // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional TranslatedImage image = 15;
-
-  // Text describing the appearance of the linked image in the `image` field (e.g., in case the image can't be displayed
-  // or the user can't see the image for accessibility reasons). See the HTML spec for alt image text - https://html.spec.whatwg.org/#alt.
-  // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional TranslatedString image_alternative_text = 16;
-
-
-  // Description of the cause of the alert that allows for agency-specific language; more specific than the Cause. If cause_detail is included, then Cause must also be included.
-  // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional TranslatedString cause_detail = 17;
-
-  // Description of the effect of the alert that allows for agency-specific language; more specific than the Effect. If effect_detail is included, then Effect must also be included.
-  // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional TranslatedString effect_detail = 18;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features
-  // and modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-//
-// Low level data structures used above.
-//
-
-// A time interval. The interval is considered active at time 't' if 't' is
-// greater than or equal to the start time and less than the end time.
-message TimeRange {
-  // Start time, in POSIX time (i.e., number of seconds since January 1st 1970
-  // 00:00:00 UTC).
-  // If missing, the interval starts at minus infinity.
-  optional uint64 start = 1;
-
-  // End time, in POSIX time (i.e., number of seconds since January 1st 1970
-  // 00:00:00 UTC).
-  // If missing, the interval ends at plus infinity.
-  optional uint64 end = 2;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// A position.
-message Position {
-  // Degrees North, in the WGS-84 coordinate system.
-  required float latitude = 1;
-
-  // Degrees East, in the WGS-84 coordinate system.
-  required float longitude = 2;
-
-  // Bearing, in degrees, clockwise from North, i.e., 0 is North and 90 is East.
-  // This can be the compass bearing, or the direction towards the next stop
-  // or intermediate location.
-  // This should not be direction deduced from the sequence of previous
-  // positions, which can be computed from previous data.
-  optional float bearing = 3;
-
-  // Odometer value, in meters.
-  optional double odometer = 4;
-  // Momentary speed measured by the vehicle, in meters per second.
-  optional float speed = 5;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// A descriptor that identifies an instance of a GTFS trip, or all instances of
-// a trip along a route.
-// - To specify a single trip instance, the trip_id (and if necessary,
-//   start_time) is set. If route_id is also set, then it should be same as one
-//   that the given trip corresponds to.
-// - To specify all the trips along a given route, only the route_id should be
-//   set. Note that if the trip_id is not known, then stop sequence ids in
-//   TripUpdate are not sufficient, and stop_ids must be provided as well. In
-//   addition, absolute arrival/departure times must be provided.
-message TripDescriptor {
-  // The trip_id from the GTFS feed that this selector refers to.
-  // For non frequency-based trips, this field is enough to uniquely identify
-  // the trip. For frequency-based trip, start_time and start_date might also be
-  // necessary. When schedule_relationship is DUPLICATED within a TripUpdate, the trip_id identifies the trip from
-  // static GTFS to be duplicated. When schedule_relationship is DUPLICATED within a VehiclePosition, the trip_id
-  // identifies the new duplicate trip and must contain the value for the corresponding TripUpdate.TripProperties.trip_id.
-  optional string trip_id = 1;
-
-  // The route_id from the GTFS that this selector refers to.
-  optional string route_id = 5;
-
-  // The direction_id from the GTFS feed trips.txt file, indicating the
-  // direction of travel for trips this selector refers to.
-  optional uint32 direction_id = 6;
-
-  // The initially scheduled start time of this trip instance.
-  // When the trip_id corresponds to a non-frequency-based trip, this field
-  // should either be omitted or be equal to the value in the GTFS feed. When
-  // the trip_id correponds to a frequency-based trip, the start_time must be
-  // specified for trip updates and vehicle positions. If the trip corresponds
-  // to exact_times=1 GTFS record, then start_time must be some multiple
-  // (including zero) of headway_secs later than frequencies.txt start_time for
-  // the corresponding time period. If the trip corresponds to exact_times=0,
-  // then its start_time may be arbitrary, and is initially expected to be the
-  // first departure of the trip. Once established, the start_time of this
-  // frequency-based trip should be considered immutable, even if the first
-  // departure time changes -- that time change may instead be reflected in a
-  // StopTimeUpdate.
-  // Format and semantics of the field is same as that of
-  // GTFS/frequencies.txt/start_time, e.g., 11:15:35 or 25:15:35.
-  optional string start_time = 2;
-  // The scheduled start date of this trip instance.
-  // Must be provided to disambiguate trips that are so late as to collide with
-  // a scheduled trip on a next day. For example, for a train that departs 8:00
-  // and 20:00 every day, and is 12 hours late, there would be two distinct
-  // trips on the same time.
-  // This field can be provided but is not mandatory for schedules in which such
-  // collisions are impossible - for example, a service running on hourly
-  // schedule where a vehicle that is one hour late is not considered to be
-  // related to schedule anymore.
-  // In YYYYMMDD format.
-  optional string start_date = 3;
-
-  // The relation between this trip and the static schedule. If a trip is done
-  // in accordance with temporary schedule, not reflected in GTFS, then it
-  // shouldn't be marked as SCHEDULED, but likely as ADDED.
-  enum ScheduleRelationship {
-    // Trip that is running in accordance with its GTFS schedule, or is close
-    // enough to the scheduled trip to be associated with it.
-    SCHEDULED = 0;
-
-    // This value has been deprecated as the behavior was unspecified. 
-    // Use DUPLICATED for an extra trip that is the same as a scheduled trip except the start date or time, 
-    // or NEW for an extra trip that is unrelated to an existing trip.
-    ADDED = 1 [deprecated = true];
-
-    // A trip that is running with no schedule associated to it (GTFS frequencies.txt exact_times=0).
-    // Trips with ScheduleRelationship=UNSCHEDULED must also set all StopTimeUpdates.ScheduleRelationship=UNSCHEDULED.
-    UNSCHEDULED = 2;
-
-    // A trip that existed in the schedule but was removed.
-    CANCELED = 3;
-
-    // A trip that replaces an existing trip in the schedule.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    REPLACEMENT = 5;
-
-    // An extra trip that was added in addition to a running schedule, for example, to replace a broken vehicle or to
-    // respond to sudden passenger load. Used with TripUpdate.TripProperties.trip_id, TripUpdate.TripProperties.start_date,
-    // and TripUpdate.TripProperties.start_time to copy an existing trip from static GTFS but start at a different service
-    // date and/or time. Duplicating a trip is allowed if the service related to the original trip in (CSV) GTFS
-    // (in calendar.txt or calendar_dates.txt) is operating within the next 30 days. The trip to be duplicated is
-    // identified via TripUpdate.TripDescriptor.trip_id. This enumeration does not modify the existing trip referenced by
-    // TripUpdate.TripDescriptor.trip_id - if a producer wants to cancel the original trip, it must publish a separate
-    // TripUpdate with the value of CANCELED or DELETED. If a producer wants to replace the original trip, a value of 
-    // `REPLACEMENT` should be used instead.
-    //
-    // Trips defined in GTFS frequencies.txt with exact_times that is
-    // empty or equal to 0 cannot be duplicated. The VehiclePosition.TripDescriptor.trip_id for the new trip must contain
-    // the matching value from TripUpdate.TripProperties.trip_id and VehiclePosition.TripDescriptor.ScheduleRelationship
-    // must also be set to DUPLICATED.
-    // Existing producers and consumers that were using the ADDED enumeration to represent duplicated trips must follow
-    // the migration guide (https://github.com/google/transit/tree/master/gtfs-realtime/spec/en/examples/migration-duplicated.md)
-    // to transition to the DUPLICATED enumeration.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    DUPLICATED = 6;
-
-
-    // A trip that existed in the schedule but was removed and must not be shown to users.
-    // DELETED should be used instead of CANCELED to indicate that a transit provider would like to entirely remove
-    // information about the corresponding trip from consuming applications, so the trip is not shown as cancelled to
-    // riders, e.g. a trip that is entirely being replaced by another trip.
-    // This designation becomes particularly important if several trips are cancelled and replaced with substitute service.
-    // If consumers were to show explicit information about the cancellations it would distract from the more important
-    // real-time predictions.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    DELETED = 7;
-
-    // An extra trip unrelated to any existing trips, for example, to respond to sudden passenger load.
-    // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-    NEW = 8;
-  }
-  optional ScheduleRelationship schedule_relationship = 4;
-
-  message ModifiedTripSelector {
-    // The 'id' from the FeedEntity in which the contained TripModifications object affects this trip.
-    optional string modifications_id = 1;
-
-    // The trip_id from the GTFS feed that is modified by the modifications_id
-    optional string affected_trip_id = 2;
-
-    // The initially scheduled start time of this trip instance, applied to the frequency based modified trip. Same definition as start_time in TripDescriptor.
-    optional string start_time = 3;
-
-    // The start date of this trip instance in YYYYMMDD format, applied to the modified trip. Same definition as start_date in TripDescriptor.
-    optional string start_date = 4;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features and
-    // modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-
-  // Linkage to any modifications done to this trip (shape changes, removal or addition of stops).
-  // If this field is provided, the `trip_id`, `route_id`, `direction_id`, `start_time`, `start_date` fields of the `TripDescriptor` MUST be left empty, to avoid confusion by consumers that aren't looking for the `ModifiedTripSelector` value.
-  optional ModifiedTripSelector modified_trip = 7;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// Identification information for the vehicle performing the trip.
-message VehicleDescriptor {
-  // Internal system identification of the vehicle. Should be unique per
-  // vehicle, and can be used for tracking the vehicle as it proceeds through
-  // the system.
-  optional string id = 1;
-
-  // User visible label, i.e., something that must be shown to the passenger to
-  // help identify the correct vehicle.
-  optional string label = 2;
-
-  // The license plate of the vehicle.
-  optional string license_plate = 3;
-
-  enum WheelchairAccessible {
-    // The trip doesn't have information about wheelchair accessibility.
-    // This is the **default** behavior. If the static GTFS contains a
-    // _wheelchair_accessible_ value, it won't be overwritten.
-    NO_VALUE = 0;
-
-    // The trip has no accessibility value present.
-    // This value will overwrite the value from the GTFS.
-    UNKNOWN = 1;
-
-    // The trip is wheelchair accessible.
-    // This value will overwrite the value from the GTFS.
-    WHEELCHAIR_ACCESSIBLE = 2;
-
-    // The trip is **not** wheelchair accessible.
-    // This value will overwrite the value from the GTFS.
-    WHEELCHAIR_INACCESSIBLE = 3;
-  }
-  optional WheelchairAccessible wheelchair_accessible = 4 [default = NO_VALUE];
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// A selector for an entity in a GTFS feed.
-message EntitySelector {
-  // The values of the fields should correspond to the appropriate fields in the
-  // GTFS feed.
-  // At least one specifier must be given. If several are given, then the
-  // matching has to apply to all the given specifiers.
-  optional string agency_id = 1;
-  optional string route_id = 2;
-  // corresponds to route_type in GTFS.
-  optional int32 route_type = 3;
-  optional TripDescriptor trip = 4;
-  optional string stop_id = 5;
-  // Corresponds to trip direction_id in GTFS trips.txt. If provided the
-  // route_id must also be provided.
-  optional uint32 direction_id = 6;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// An internationalized message containing per-language versions of a snippet of
-// text or a URL.
-// One of the strings from a message will be picked up. The resolution proceeds
-// as follows:
-// 1. If the UI language matches the language code of a translation,
-//    the first matching translation is picked.
-// 2. If a default UI language (e.g., English) matches the language code of a
-//    translation, the first matching translation is picked.
-// 3. If some translation has an unspecified language code, that translation is
-//    picked.
-message TranslatedString {
-  message Translation {
-    // A UTF-8 string containing the message.
-    required string text = 1;
-    // BCP-47 language code. Can be omitted if the language is unknown or if
-    // no i18n is done at all for the feed. At most one translation is
-    // allowed to have an unspecified language tag.
-    optional string language = 2;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features and
-    // modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-  // At least one translation must be provided.
-  repeated Translation translation = 1;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// An internationalized image containing per-language versions of a URL linking to an image
-// along with meta information
-// Only one of the images from a message will be retained by consumers. The resolution proceeds
-// as follows:
-// 1. If the UI language matches the language code of a translation,
-//    the first matching translation is picked.
-// 2. If a default UI language (e.g., English) matches the language code of a
-//    translation, the first matching translation is picked.
-// 3. If some translation has an unspecified language code, that translation is
-//    picked.
-// NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-message TranslatedImage {
-  message LocalizedImage {
-    // String containing an URL linking to an image
-    // The image linked must be less than 2MB. 
-    // If an image changes in a significant enough way that an update is required on the consumer side, the producer must update the URL to a new one.
-    // The URL should be a fully qualified URL that includes http:// or https://, and any special characters in the URL must be correctly escaped. See the following http://www.w3.org/Addressing/URL/4_URI_Recommentations.html for a description of how to create fully qualified URL values.
-    required string url = 1;
-
-    // IANA media type as to specify the type of image to be displayed. 
-    // The type must start with "image/"
-    required string media_type = 2;
-
-    // BCP-47 language code. Can be omitted if the language is unknown or if
-    // no i18n is done at all for the feed. At most one translation is
-    // allowed to have an unspecified language tag.
-    optional string language = 3;
-
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features and
-    // modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-  // At least one localized image must be provided.
-  repeated LocalizedImage localized_image = 1;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// Describes the physical path that a vehicle takes when it's not part of the (CSV) GTFS,
-// such as for a detour. Shapes belong to Trips, and consist of a sequence of shape points.
-// Tracing the points in order provides the path of the vehicle.  Shapes do not need to intercept
-// the location of Stops exactly, but all Stops on a trip should lie within a small distance of
-// the shape for that trip, i.e. close to straight line segments connecting the shape points
-// NOTE: This message is still experimental, and subject to change. It may be formally adopted in the future.
-message Shape {
-  // Identifier of the shape. Must be different than any shape_id defined in the (CSV) GTFS.
-  // This field is required as per reference.md, but needs to be specified here optional because "Required is Forever"
-  // See https://developers.google.com/protocol-buffers/docs/proto#specifying_field_rules
-  // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional string shape_id = 1;
-
-  // Encoded polyline representation of the shape. This polyline must contain at least two points and represent the full shape of the trip where it's used. 
-  // For more information about encoded polylines, see https://developers.google.com/maps/documentation/utilities/polylinealgorithm
-  // This field is required as per reference.md, but needs to be specified here optional because "Required is Forever"
-  // See https://developers.google.com/protocol-buffers/docs/proto#specifying_field_rules
-  // NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-  optional string encoded_polyline = 2;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// Describes a stop which is served by trips. All fields are as described in the GTFS-Static specification.
-// NOTE: This message is still experimental, and subject to change. It may be formally adopted in the future.
-message Stop {
-  enum WheelchairBoarding {
-    UNKNOWN = 0;
-    AVAILABLE = 1;
-    NOT_AVAILABLE = 2;
-  }
-
-  optional string stop_id = 1;
-  optional TranslatedString stop_code = 2;
-  optional TranslatedString stop_name = 3;
-  optional TranslatedString tts_stop_name = 4;
-  optional TranslatedString stop_desc = 5;
-  optional float stop_lat = 6;
-  optional float stop_lon = 7;
-  optional string zone_id = 8;
-  optional TranslatedString stop_url = 9;
-  optional string parent_station = 11;
-  optional string stop_timezone = 12;
-  optional WheelchairBoarding wheelchair_boarding = 13 [default = UNKNOWN];
-  optional string level_id = 14;
-  optional TranslatedString platform_code = 15;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-message TripModifications {
-  // A `Modification` message replaces a span of n stop times from each affected trip starting at `start_stop_selector`.
-  message Modification {
-    // The stop selector of the first stop_time of the original trip that is to be affected by this modification.
-    // Used in conjuction with `end_stop_selector`. 
-    // `start_stop_selector` is required and is used to define the reference stop used with `travel_time_to_stop`.
-    optional StopSelector start_stop_selector = 1;
-
-    // The stop selector of the last stop of the original trip that is to be affected by this modification. 
-    // The selection is inclusive, so if only one stop_time is replaced by that modification, `start_stop_selector` and `end_stop_selector` must be equivalent.
-    // If no stop_time is replaced, `end_stop_selector` must not be provided. It's otherwise required.
-    optional StopSelector end_stop_selector = 2;
-
-    // The number of seconds of delay to add to all departure and arrival times following the end of this modification. 
-    // If multiple modifications apply to the same trip, the delays accumulate as the trip advances. 
-    optional int32 propagated_modification_delay = 3 [default = 0];
-
-    // A list of replacement stops, replacing those of the original trip. 
-    // The length of the new stop times may be less, the same, or greater than the number of replaced stop times. 
-    repeated ReplacementStop replacement_stops = 4;
-
-    // An `id` value from the `FeedEntity` message that contains the `Alert` describing this Modification for user-facing communication.
-    optional string service_alert_id = 5;
-
-    // This timestamp identifies the moment when the modification has last been changed.
-    // In POSIX time (i.e., number of seconds since January 1st 1970 00:00:00 UTC).
-    optional uint64 last_modified_time = 6;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features and
-    // modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-
-  message SelectedTrips {
-    // A list of trips affected with this replacement that all have the same new `shape_id`. A `TripUpdate` with `schedule_relationship=REPLACEMENT` must not already exist for the trip.
-    repeated string trip_ids = 1;
-    // The ID of the new shape for the modified trips in this SelectedTrips. 
-    // May refer to a new shape added using a `Shape` message in the same GTFS-RT feed, or to an existing shape defined in the GTFS-Static feed’s shapes.txt. 
-    // If it refers to a `Shape` entity in the real-time feed, the value of this field should be the one of the `shape_id` inside the entity, and _not_ the `id` of `FeedEntity`.
-    optional string shape_id = 2;
-
-    // The extensions namespace allows 3rd-party developers to extend the
-    // GTFS Realtime Specification in order to add and evaluate new features and
-    // modifications to the spec.
-    extensions 1000 to 1999;
-
-    // The following extension IDs are reserved for private use by any organization.
-    extensions 9000 to 9999;
-  }
-
-  // A list of selected trips affected by this TripModifications.
-  repeated SelectedTrips selected_trips = 1;
-
-  // A list of start times in the real-time trip descriptor for the trip_id defined in trip_ids. 
-  // Useful to target multiple departures of a trip_id in a frequency-based trip.
-  repeated string start_times = 2;
-
-  // Dates on which the modifications occurs, in the YYYYMMDD format. Producers SHOULD only transmit detours occurring within the next week.
-  // The dates provided should not be used as user-facing information, if a user-facing start and end date needs to be provided, they can be provided in the linked service alert with `service_alert_id`
-  repeated string service_dates = 3;
-
-  // A list of modifications to apply to the affected trips. 
-  repeated Modification modifications = 4;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-// Select a stop by stop sequence or by stop_id. At least one of the two values must be provided.
-message StopSelector {
-  // Must be the same as in stop_times.txt in the corresponding GTFS feed.
-  optional uint32 stop_sequence = 1;
-  // Must be the same as in stops.txt in the corresponding GTFS feed.
-  optional string stop_id = 2;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
-
-// NOTE: This field is still experimental, and subject to change. It may be formally adopted in the future.
-message ReplacementStop {
-  // The difference in seconds between the arrival time at this stop and the arrival time at the reference stop. The reference stop is the stop prior to start_stop_selector. If the modification begins at the first stop of the trip, then the first stop of the trip is the reference stop.
-  // This value MUST be monotonically increasing and may only be a negative number if the first stop of the original trip is the reference stop.
-  optional int32 travel_time_to_stop = 1;
-
-  // The replacement stop ID which will now be visited by the trip. May refer to a new stop added using a GTFS-RT `Stop` message in the same GTFS-RT feed, or to an existing stop defined in the (CSV) GTFS feed’s `stops.txt`.
-  // If it refers to a `Shape` entity in the real-time feed, the value of this field should be the one of the `stop_id` inside the entity, and _not_ the `id` of `FeedEntity`. The replacement stop MUST have `location_type=0` (routable stops).
-  optional string stop_id = 2;
-
-  // The extensions namespace allows 3rd-party developers to extend the
-  // GTFS Realtime Specification in order to add and evaluate new features and
-  // modifications to the spec.
-  extensions 1000 to 1999;
-
-  // The following extension IDs are reserved for private use by any organization.
-  extensions 9000 to 9999;
-}
\ No newline at end of file