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// 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;
}
// Metadata about a feed, included in feed messages.
message FeedHeader {
// Version of the feed specification.
// The current version is 2.0.
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;
// 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;
}
// 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;
// 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;
}
//
// 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;
// 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;
}
// 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;
// The relation between this StopTime 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.
SCHEDULED = 0;
// The stop is skipped, i.e., the vehicle will not stop at this stop.
// Arrival and departure are optional.
SKIPPED = 1;
// No data is given for this stop. The main intention for this value is to
// give the predictions only for part of a trip, i.e., if the last update
// for a trip has a NO_DATA specifier, then StopTimes 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;
}
optional ScheduleRelationship schedule_relationship = 5
[default = SCHEDULED];
// 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;
}
// 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;
// Moment at which the vehicle's real-time progress was measured. 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;
// 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;
}
// 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 degree of passenger occupancy of the vehicle. This field is still
// experimental, and subject to change. It may be formally adopted in the
// future.
enum OccupancyStatus {
// The vehicle is considered empty by most measures, and has few or no
// passengers onboard, but is still accepting passengers.
EMPTY = 0;
// The vehicle has a relatively large percentage of seats available.
// What percentage of free seats out of the total seats available is to be
// considered large enough to fall into this category is determined at the
// discretion of the producer.
MANY_SEATS_AVAILABLE = 1;
// The vehicle has a relatively small percentage of seats available.
// What percentage of free seats out of the total seats available is 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 can currently accommodate only standing passengers.
STANDING_ROOM_ONLY = 3;
// The vehicle can currently accommodate only standing passengers
// and has limited space for them.
CRUSHED_STANDING_ROOM_ONLY = 4;
// The vehicle is considered full by most measures, but may still be
// allowing passengers to board.
FULL = 5;
// The vehicle is not accepting additional passengers.
NOT_ACCEPTING_PASSENGERS = 6;
}
optional OccupancyStatus occupancy_status = 9;
// 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;
}
// 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.
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.
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;
}
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;
// 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;
}
//
// 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;
}
// 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;
}
// 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.
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. This field is
// still experimental, and subject to change. It may be formally adopted in
// the future.
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;
// 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.
ADDED = 1;
// A trip that is running with no schedule associated to it, for example, if
// there is no schedule at all.
UNSCHEDULED = 2;
// A trip that existed in the schedule but was removed.
CANCELED = 3;
}
optional ScheduleRelationship schedule_relationship = 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;
}
// 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;
// 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;
}
// 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;
// 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;
}
// 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;
}
// 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;
}