[GTFS-Fares v2] Add Distance-Based Fares

gtfs/spec/en/reference.md

@@ -63,6 +63,8 @@ This section defines terms that are used throughout this document.
 * **Sub-journey** - Two or more legs that comprise a subset of a journey.
 * **Fare product** - Purchassable fare products that can be used to pay for or validate travel.
 * **Effective Fare Leg** - A sub-journey of two or more legs that should be treated as a single leg for matching rules in [fare_leg_rules.txt](#fare_leg_rulestxt) for the purposes of fare calculation.
+* **Distance Unit** (or Fare distance unit) - Any unit used to calculate the fare for distance-based fare structures. The unit can be a distance measure (e.g., meters, kilometers, miles) or any other incremental unit (e.g., number of stops crossed). The distance unit does not necessarily correspond to a physical measure of distance. It may also be adjusted by adding or subtracting arbitrary values to represent fare discounts or supplements.
+* **Distance-Based Leg** - A leg whose fare is based on the distance units traveled. In [fare_leg_rules.txt](#fare_leg_rulestxt), a distance-based leg is a leg that has at least `fare_leg_rules.min_distance_units` or `fare_leg_rules.max_distance_units` assigned (not empty).
 
 
 ### Presence
@@ -304,6 +306,7 @@ Primary key (`trip_id`, `stop_sequence`)
 |  `continuous_pickup` | Enum | **Conditionally Forbidden** | Indicates that the rider can board the transit vehicle at any point along the vehicle’s travel path as described by [shapes.txt](#shapestxt), from this `stop_time` to the next `stop_time` in the trip’s `stop_sequence`. Valid options are: <br><br>`0` - Continuous stopping pickup. <br>`1` or empty - No continuous stopping pickup. <br>`2` - Must phone agency to arrange continuous stopping pickup. <br>`3` - Must coordinate with driver to arrange continuous stopping pickup.  <br><br>If this field is populated, it overrides any continuous pickup behavior defined in [routes.txt](#routestxt). If this field is empty, the `stop_time` inherits any continuous pickup behavior defined in [routes.txt](#routestxt).<br><br>**Conditionally Forbidden**:<br>- **Forbidden** if `start_pickup_drop_off_window` or `end_pickup_drop_off_window` are defined.<br> - Optional otherwise. |
 |  `continuous_drop_off` | Enum | **Conditionally Forbidden** | Indicates that the rider can alight from the transit vehicle at any point along the vehicle’s travel path as described by [shapes.txt](#shapestxt), from this `stop_time` to the next `stop_time` in the trip’s `stop_sequence`. Valid options are: <br><br>`0` - Continuous stopping drop off. <br>`1` or empty - No continuous stopping drop off. <br>`2` - Must phone agency to arrange continuous stopping drop off. <br>`3` - Must coordinate with driver to arrange continuous stopping drop off. <br><br>If this field is populated, it overrides any continuous drop-off behavior defined in [routes.txt](#routestxt). If this field is empty, the `stop_time` inherits any continuous drop-off behavior defined in [routes.txt](#routestxt).<br><br>**Conditionally Forbidden**:<br>- **Forbidden** if `start_pickup_drop_off_window` or `end_pickup_drop_off_window` are defined.<br> - Optional otherwise. |
 |  `shape_dist_traveled` | Non-negative float | Optional | Actual distance traveled along the associated shape, from the first stop to the stop specified in this record. This field specifies how much of the shape to draw between any two stops during a trip. Must be in the same units used in [shapes.txt](#shapestxt). Values used for `shape_dist_traveled` must increase along with `stop_sequence`; they must not be used to show reverse travel along a route.<br><br>Recommended for routes that have looping or inlining (the vehicle crosses or travels over the same portion of alignment in one trip). See [`shapes.shape_dist_traveled`](#shapestxt). <hr>*Example: If a bus travels a distance of 5.25 kilometers from the start of the shape to the stop,`shape_dist_traveled`=`5.25`.*|
+|  `fare_distance_units_traveled` | Non-negative integer | Conditionally Required | Fare distance units traveled along the trip, from the first stop to the stop specified in this record. `fare_distance_units_traveled` is used to match a fare leg rule from [fare_leg_rules.txt](#fare_leg_rulestxt) whose distance interval [`min_distance_units`, `max_distance_units`] includes the `fare_distance_units_traveled` covered so far in the journey starting from the stop that the rider boards at (the difference between `fare_distance_units_traveled` at the destination and `fare_distance_units_traveled` at the origin of the trip). <br><br> `fare_distance_units_traveled` does not have to be in the same unit as `stop_times.shape_dist_traveled`. <br><br> If the fare is calculated based on the distance covered by the route shape, `fare_distance_units_traveled` may correspond to `stop_times.shape_dist_traveled` (measured in meters) or to its rounded value (floor or ceiling), depending on the fare structure. If the fare is calculated based on stops, `fare_distance_units_traveled` may represent the number of stops crossed. `fare_distance_units_traveled` may also be adjusted by adding or subtracting arbitrary values to represent fare discounts or supplements. <br><br> **Conditionally Required** <br>- Required if the `route_id` of the `trip_id` of this stop time is part of a `network_id` which is associated to a distance-based `leg_group_id` in `fare_leg_rules.txt`.<br> - Forbidden otherwise.|
 |  `timepoint` | Enum | Optional | Indicates if arrival and departure times for a stop are strictly adhered to by the vehicle or if they are instead approximate and/or interpolated times. This field allows a GTFS producer to provide interpolated stop-times, while indicating that the times are approximate. Valid options are:<br><br>`0` - Times are considered approximate. <br>`1` - Times are considered exact. <br><br> All records of [stop_times.txt](#stop_timestxt) with defined arrival or departure times should have timepoint values populated. If no timepoint values are provided, all times are considered exact. |
 | `pickup_booking_rule_id` | Foreign ID referencing `booking_rules.booking_rule_id` | Optional | Identifies the boarding booking rule at this stop time.<br><br>Recommended when `pickup_type=2`. |
 | `drop_off_booking_rule_id` | Foreign ID referencing `booking_rules.booking_rule_id` | Optional | Identifies the alighting booking rule at this stop time.<br><br>Recommended when `drop_off_type=2`. |
@@ -463,7 +466,7 @@ Used to describe the range of fares available for purchase by riders or taken in
 
 File: **Optional**
 
-Primary key (`network_id, from_area_id, to_area_id, from_timeframe_group_id, to_timeframe_group_id, fare_product_id`)
+Primary key (`network_id, from_area_id, to_area_id, from_timeframe_group_id, to_timeframe_group_id, min_distance_units, max_distance_units, fare_product_id`)
 
 Fare rules for individual legs of travel.
 
@@ -477,6 +480,8 @@ To process the cost of a leg:
     - `fare_leg_rules.to_area_id`
     - `fare_leg_rules.from_timeframe_group_id`
     - `fare_leg_rules.to_timeframe_group_id`
+    - `fare_leg_rules.min_distance_units`
+    - `fare_leg_rules.max_distance_units`
 <br/>
 
 2. If the leg exactly matches a record in [fare_leg_rules.txt](#fare_leg_rulestxt) based on the characteristics of travel, that record must be processed to determine the cost of the leg. This file handles empty entries in two ways: empty semantics OR rule_priority.
@@ -507,6 +512,8 @@ To process the cost of a leg:
 | `to_area_id` | Foreign ID referencing `areas.area_id` | Optional | Identifies an arrival area.<br><br>If the `rule_priority` field does not exist AND there are no matching `fare_leg_rules.to_area_id` values to the `area_id` being filtered, empty `fare_leg_rules.to_area_id` will be matched by default.<br><br> An empty entry in `fare_leg_rules.to_area_id` corresponds to all areas defined in `areas.area_id` excluding the ones listed under `fare_leg_rules.to_area_id`<br><br>If the `rule_priority` field exists in the file, an empty `fare_leg_rules.to_area_id` indicates that the arrival area of the leg does not affect the matching of this rule.<br><br>When matching against an [effective fare leg of multiple legs](#fare_leg_join_rulestxt), the last leg of the effective fare leg is used for determining the arrival area. |
 |  `from_timeframe_group_id` | Foreign ID referencing `timeframes.timeframe_group_id` | Optional |  Defines the timeframe for the fare validation event at the start of the fare leg.<br><br>The “start time” of the fare leg is the time at which the event is scheduled to occur.  For example, the time could be the scheduled departure time of a bus at the start of a fare leg where the rider boards and validates their fare. For the rule matching semantics below, the start time is computed in local time, as determined by [Local Time Semantics](#localtimesemantics) of [timeframes.txt](#timeframestxt).  The stop or station of the fare leg’s departure event should be used for timezone resolution, where appropriate.<br><br>For a fare leg rule that specifies a `from_timeframe_group_id`, that rule will match a particular leg if there exists at least one record in [timeframes.txt](#timeframestxt) where all of the following conditions are true<br>- The value of `timeframe_group_id` is equal to the `from_timeframe_group_id` value.<br>- The set of days identified by the record’s `service_id` contains the “current day” of the fare leg’s start time.<br>- The “time-of-day” of the fare leg's start time is greater than or equal to the record’s `timeframes.start_time` value and less than the `timeframes.end_time` value.<br><br>An empty `fare_leg_rules.from_timeframe_group_id` indicates that the start time of the leg does not affect the matching of this rule.<br><br>When matching against an [effective fare leg of multiple legs](#fare_leg_join_rulestxt), the first leg of the effective fare leg is used for determining the starting fare validation event. |
 |  `to_timeframe_group_id` |  Foreign ID referencing `timeframes.timeframe_group_id` | Optional |  Defines the timeframe for the fare validation event at the end of the fare leg.<br><br>The “end time” of the fare leg is the time at which the event is scheduled to occur.  For example, the time could be the scheduled arrival time of a bus at the end of a fare leg where the rider gets off and validates their fare.  For the rule matching semantics below, the end time is computed in local time, as determined by [Local Time Semantics](#localtimesemantics) of [timeframes.txt](#timeframestxt).  The stop or station of the fare leg’s arrival event should be used for timezone resolution, where appropriate.<br><br>For a fare leg rule that specifies a `to_timeframe_group_id`, that rule will match a particular leg if there exists at least one record in [timeframes.txt](#timeframestxt) where all of the following conditions are true<br>- The value of `timeframe_group_id` is equal to the `to_timeframe_group_id` value.<br>- The set of days identified by the record’s `service_id` contains the “current day” of the fare leg’s end time.<br>- The “time-of-day” of the fare leg's end time is greater than or equal to the record’s `timeframes.start_time` value and less than the `timeframes.end_time` value.<br><br>An empty `fare_leg_rules.to_timeframe_group_id` indicates that the end time of the leg does not affect the matching of this rule.<br><br>When matching against an [effective fare leg of multiple legs](#fare_leg_join_rulestxt), the last leg of the effective fare leg is used for determining the ending fare validation event. |
+| `min_distance_units` | Non-negative integer | Optional | Minimum travel distance units required for the fare leg rule. `min_distance_units` is included in the lower bound of the interval.<br><br>For a fare leg rule that specifies a `min_distance_units`, the leg rule will match a particular leg where `min_distance_units` is less than or equal to the leg's `stop_times.fare_distance_units_traveled` (or sum of `stop_times.fare_distance_units_traveled` for effective fare legs).<br><br> Only `stop_times.fare_distance_units_traveled` can be used to match legs for distance-based leg rules, `stop_times.stop_sequence` and `stop_times.shape_dist_traveled` cannot be used to match legs. <br><br> If the lowest distance bound is zero, `fare_leg_rules.min_distance_units` can be empty. Otherwise, `fare_leg_rules.min_distance_units` must be less than `fare_leg_rules.max_distance_units`.|
+| `max_distance_units` | Non-negative integer | Optional | Maximum travel distance units required for the fare leg rule. `max_distance_units` is excluded from the upper bound of the interval. <br><br>For a fare leg rule that specifies a `max_distance_units`, the leg rule will match a particular leg where `max_distance_units` is strictly greater than the leg's `stop_times.fare_distance_units_traveled` (or sum of `stop_times.fare_distance_units_traveled` for effective fare legs).<br><br> Only `stop_times.fare_distance_units_traveled` can be used to match legs for distance-based leg rules, `stop_times.stop_sequence` and `stop_times.shape_dist_traveled` cannot be used to match legs.<br><br> If the upper distance bound is undefined (i.e., the conceptual upper limit), `fare_leg_rules.max_distance_units` can be empty. Otherwise, `fare_leg_rules.max_distance_units` must be greater than `fare_leg_rules.min_distance_units`.|
 | `fare_product_id` | Foreign ID referencing `fare_products.fare_product_id` | **Required** | The fare product required to travel the leg. |
 | `rule_priority` | Non-negative integer | Optional | Defines the order of priority in which matching rules are applied to legs, allowing certain rules to take precedence over others. When multiple entries in `fare_leg_rules.txt` match, the rule or set of rules with the highest value for `rule_priority` will be selected.<br><br>An empty value for `rule_priority` is treated as zero. |
 
@@ -520,13 +527,17 @@ For a sub-journey of two consecutive legs with a transfer, if the transfer match
 - Unless overridden explicitly by `from_stop_id` and `to_stop_id`, the last station of the pre-transfer leg and the first station of the post-transfer leg must be the same for the record.
 - If a matching predicate field value is blank or unspecified for a particular record in the file, then that field should be ignored for the purposes of matching.
 - When a sub-journey contains consecutive transfers that each match a join rule, then the entire sub-journey should be considered as a single **effective fare leg**.
+- In the case of distance-based legs, the effective leg's total distance is the sum of the distances of its legs.
 
 |  Field Name | Type | Presence | Description |
 |  ------ | ------ | ------ | ------ |
-| `from_network_id` | Foreign ID referencing `routes.network_id` or `networks.network_id`| **Required** | Matches a pre-transfer leg that uses the specified route network.  If specified, the same `to_network_id` must also be specified. |
-| `to_network_id` | Foreign ID referencing `routes.network_id` or `networks.network_id`| **Required** | Matches a post-transfer leg that uses the specified route network.  If specified, the same `from_network_id` must also be specified. |
+| `from_network_id` | Foreign ID referencing `routes.network_id` or `networks.network_id`| **Required** | Matches a pre-transfer leg that uses the specified route network.  If specified, the same `to_network_id` must also be specified.<br><br>If `to_network_id` is associated with at least one distance-based `leg_group_id` in `fare_leg_rules.txt`, then `from_network_id` needs to be associated with at least one distance-based `leg_group_id` in `fare_leg_rules.txt`. (A distance-based leg cannot be joined with a leg that is not distance-based).|
+| `to_network_id` | Foreign ID referencing `routes.network_id` or `networks.network_id`| **Required** | Matches a post-transfer leg that uses the specified route network.  If specified, the same `from_network_id` must also be specified.<br><br>If `from_network_id` is associated with at least one distance-based `leg_group_id` in `fare_leg_rules.txt`, then `to_network_id` needs to be associated with at least one distance-based `leg_group_id` in `fare_leg_rules.txt`. (A distance-based leg cannot be joined with a leg that is not distance-based).|
 | `from_stop_id` | Foreign ID referencing `stops.stop_id`| **Conditionally Required** | Matches a pre-transfer leg that ends at the specified stop (`location_type=0` or empty) or station (`location_type=1`).<br><br>Conditionally Required:<br> - **Required** if `to_stop_id` is defined.<br> - Optional otherwise. |
 | `to_stop_id` | Foreign ID referencing `stops.stop_id`| **Conditionally Required** | Matches a post-transfer leg that starts at the specified stop (`location_type=0` or empty) or station (`location_type=1`).<br><br>Conditionally Required:<br> - **Required** if `from_stop_id` is defined.<br> - Optional otherwise. |
+| `duration_limit` | Positive integer | **Optional** | Defines the duration limit of the transfer between the legs that constitute the effective leg. <br><br>Must be expressed in integer increments of seconds.<br><br>If there is no duration limit, `fare_leg_join_rules.duration_limit` must be empty. |
+| `duration_limit_type` | Enum | **Conditionally Required** | Defines the relative start and end of `fare_leg_join_rules.duration_limit`.<br><br>Valid options are:<br>`0` - Between the departure fare validation of the first leg in the effective leg and the arrival fare validation of the last leg in the effective leg.<br>`1` - Between the departure fare validation of the first leg in the effective leg and the departure fare validation of the last leg in the effective leg.<br>`2` - Between the arrival fare validation of the first leg in the effective leg and the departure fare validation of the last leg in the effective leg.<br>`3` - Between the arrival fare validation of the first leg in the effective leg and the arrival fare validation of the last leg in the effective leg.<br><br>When an effective leg with the same `from_network_id` and `to_network_id` is matched multiple times consecutively within a multi-leg journey, the `duration_limit` specified by the effective leg should be measured starting from the first matched leg.<br><br>Conditionally Required:<br>- **Required** if `fare_leg_join_rules.duration_limit` is defined.<br>- **Forbidden** if `fare_leg_join_rules.duration_limit` is empty. |
+
 
 ### fare_transfer_rules.txt