Update network fetching to be more generic

This commit is contained in:
Mattéo Delabre 2022-07-04 22:40:29 -04:00
parent aeef4b5ae9
commit 17d36a032c
Signed by: matteo
GPG Key ID: AE3FBD02DC583ABB
4 changed files with 1437 additions and 26851 deletions

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@ -3,8 +3,13 @@
import * as network from '../src/tam/network.js'; import * as network from '../src/tam/network.js';
import fs from 'fs/promises'; import fs from 'fs/promises';
const lines = ['1', '2', '3', '4']; /** Geographical bounds of the Montpellier metropolitan area. */
const data = await network.fetch(lines); const bounds = [
"43.49552248630757", "3.660507202148437",
"43.73736766145917", "4.092750549316406",
];
const data = await network.fetch("TaM", "tram", bounds);
await fs.writeFile( await fs.writeFile(
new URL("../src/tam/network.json", import.meta.url), new URL("../src/tam/network.json", import.meta.url),

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@ -17,33 +17,24 @@ import * as util from "../util.js";
import * as osm from "./sources/osm.js"; import * as osm from "./sources/osm.js";
/** /**
* Route of a line of a transport network. * Rectangle area of geographical points.
* @typedef {Object} Route *
* @property {string} from Name of the starting point of the route. * Should contain four values, [lat1, lon1, lat2, lon2], corresponding to two
* @property {string} to Name of the ending point of the route. * opposed corners of the rectangle.
* @property {string?} via Optional name of a major intermediate * @typedef {Array.<string>} Bounds
* stop of the route.
* @property {string} name Human-readable name of the line.
*/
/**
* Line of a transport network.
* @typedef {Object} Line
* @property {string} color Hexadecimal color code of this line.
* @property {Array.<Route>} routes Routes of this line.
*/ */
/** /**
* Stop in a transport network (as a GeoJSON feature point). * Stop in a transport network (as a GeoJSON feature point).
* @typedef {Object} Stop * @typedef {Object} Stop
* @property {string} type Always equal to "Feature". * @property {string} type Always equal to "Feature".
* @property {string} id Stop identifier (unique in each network.). * @property {string} id Stop identifier (unique in each network).
* @property {Object} properties * @property {Object} properties
* @property {string} properties.name Human-readable name of the stop. * @property {string} properties.name Human-readable name of the stop.
* @property {string} properties.node Associated node ID in OpenStreetMap. * @property {string} properties.node Associated node ID in OpenStreetMap.
* @property {Array.<Array.[string,number]>} properties.routes * @property {Array.<Array.[string,number]>} properties.routes
* List of transport lines using this stop (as pairs of * List of transport lines using this stop (as pairs containing the
* line and route identifiers). * line number and line route identifier).
* @property {Object} geometry * @property {Object} geometry
* @property {string} geometry.type Always equal to "Point" * @property {string} geometry.type Always equal to "Point"
* @property {Array.<number>} geometry.coordinates * @property {Array.<number>} geometry.coordinates
@ -51,295 +42,66 @@ import * as osm from "./sources/osm.js";
*/ */
/** /**
* Planned segment routing between two stops of a transport network * Find all public transport stops matching a set of criteria.
* (as a GeoJSON feature line string). * @param {string} network Name of the public transport network
* @typedef {Object} Segment * to which the stops must belong.
* @property {string} type Always equal to "Feature". * @param {string} type Type of public transport vehicle.
* @property {string} id Segment identifier (format: `{begin}-{end}`). * @param {Bounds} bounds Area in which stops are searched.
* @property {Object} properties * @return {Object.<string,Stop>} List of stops indexed by their ID.
* @property {string} properties.begin ID of the stop at the beginning.
* @property {string} properties.end ID of the stop at the end.
* @property {number} properties.length Length of this segment (meters).
* @property {Array.<Array.[string,number]>} properties.routes
* List of transport lines using this segment (as pairs of
* line identifiers and line direction numbers).
* @property {Object} geometry
* @property {string} geometry.type Always equal to "LineString".
* @property {Array.<Array.<number>>} geometry.coordinates
* Sequence of points forming this segment (as longitude/latitude pairs).
*/ */
const fetchStops = async (network, type, bounds) => {
const filter = osm.buildFilter({
public_transport: "stop_position",
ref: true,
network,
[type]: "yes",
});
const elementsList = (await osm.runQuery(`[out:json];
node${filter}(${bounds});
out body qt;
`)).elements;
const stops = {};
for (const stop of elementsList) {
stops[stop.tags.ref] = turfHelpers.point([
stop.lon,
stop.lat,
], {
name: stop.tags.name,
node: stop.id.toString(),
routes: [],
}, {
id: stop.tags.ref,
});
}
return stops;
};
/** /**
* Edge of the graph for navigating between stops. * Route between two OpenStreetMap nodes.
* @typedef {Object} NavigationEdge * @typedef {Object} NavigationEdge
* @property {string} type Always equal to "Feature". * @property {string} type Always equal to "Feature".
* @property {Object} properties * @property {Object} properties
* @property {string} properties.begin ID of the stop or node at the beginning. * @property {string} properties.begin ID of the node at the beginning.
* @property {string} properties.end ID of the stop or node at the end. * @property {string} properties.end ID of the node at the end.
* @property {number} properties.length Length of this edge (meters). * @property {number} properties.length Length of this path (meters).
* @property {Object} geometry * @property {Object} geometry
* @property {string} geometry.type Always equal to "LineString". * @property {string} geometry.type Always equal to "LineString".
* @property {Array.<Array.<number>>} geometry.coordinates * @property {Array.<Array.<number>>} geometry.coordinates
* Sequence of points forming this edge (as longitude/latitude pairs). * Sequence of points along this route (as longitude/latitude pairs).
*/ */
/** /**
* Graph for navigating between stops. * Navigation graph between OpenStreetMap nodes.
* @typedef {Object.<string,Object.<string,NavigationEdge>>} Navigation * @typedef {Object.<string,Object.<string,NavigationEdge>>} Navigation
*/ */
/** /**
* Information about a public transport network. * Assemble a raw navigation graph from OSM data.
* @typedef {Object} Network * @param {Array.<Object>} elementsList List of elements retrieved from OSM.
* @property {Object.<string,Stop>} stops List of stops. * @param {Object.<string,Object>} elementsById OSM elements indexed by ID.
* @property {Object.<string,Line>} lines List of lines.
* @property {Object.<string,Segment>} segments List of segments.
* @property {Navigation} navigation
* Graph for out-of-route navigation between stops.
*/
/**
* Retrieve raw routes, ways and stops from OpenStreetMap for the given
* transport lines.
* @param {Array.<string>} lineRefs List of lines to fetch.
* @return {Array.<Object>} List of objects returned by OSM.
*/
// Retrieve routes, ways and stops from OpenStreetMap
const queryLines = async lineRefs => {
return (await osm.runQuery(`[out:json];
// Find the public transport lines bearing the requested references
relation[network="TaM"][type="route_master"][ref~"^(${lineRefs.join("|")})$"];
(
._;
// Recursively fetch routes, ways and stops inside the lines
>>;
// Find adjacent tracks (used for out-of-route navigation)
complete {
way(around:0)[railway="tram"];
};
>;
);
out body qt;
`)).elements;
};
/**
* Assemble information about lines, stops and segments from the raw
* OpenStreetMap data.
* @param {Array.<Object>} elementsList List of nodes retrieved from OSM.
* @param {Object.<string,Object>} elementsById OSM nodes indexed by their ID.
* @return {Object} Assembled information about lines, stops and segments.
*/
const processRoutes = (elementsList, elementsById) => {
const lines = {};
const stops = {};
const segments = {};
const routeMasters = elementsList.filter(osm.isTransportLine);
// Extract lines, associated stops and planned routes
for (const routeMaster of routeMasters) {
const lineRef = routeMaster.tags.ref;
const color = routeMaster.tags.colour || "#000000";
const routes = [];
for (const [routeRef, data] of routeMaster.members.entries()) {
const routeId = data.ref;
const route = elementsById[routeId];
const { from, via, to, name } = route.tags;
const state = route.tags.state || "normal";
// Add missing stops to the global stops object
for (const { ref, role } of route.members) {
if (role === "stop") {
const stop = elementsById[ref];
if (!("ref" in stop.tags)) {
throw new Error(`Stop ${stop.id}
(${osm.viewNode(stop.id)}) on line ${route.tags.name} is missing
a ref tag`);
}
if (!(stop.tags.ref in stops)) {
stops[stop.tags.ref] = turfHelpers.point([
stop.lon,
stop.lat
], {
name: stop.tags.name,
node: ref.toString(),
routes: [[lineRef, routeRef]],
}, {
id: stop.tags.ref,
});
} else {
stops[stop.tags.ref].properties.routes.push([
lineRef,
routeRef
]);
}
}
}
// Check that the route consists of a block of stops and platforms
// followed by a block of routes as dictated by PTv2
const relationPivot = route.members.findIndex(
({ role }) => role === ""
);
if (!route.members.slice(0, relationPivot).every(
({ role }) => role === "stop" || role === "platform"
)) {
throw new Error(`Members with invalid roles in between stops
of ${name}`);
}
if (!route.members.slice(relationPivot).every(
({ role }) => role === ""
)) {
throw new Error(`Members with invalid roles inside the path
of ${name}`);
}
// List of stops in the route, expected to be in the timetable
// order as per PTv2 and to be traversed in order by the sequence
// of ways extracted below
const lineStops = route.members.slice(0, relationPivot)
.filter(({ role }) => role === "stop")
.map(({ ref }) => ref);
// List of ways making up the routes path through its stops
// with each way connected to the next through a single point
const ways = route.members.slice(relationPivot)
.map(({ ref }) => ref);
// Merge all used ways in a single path
let path = [];
let currentNode = lineStops[0];
for (let wayIndex = 0; wayIndex < ways.length; wayIndex += 1) {
const way = elementsById[ways[wayIndex]];
const { nodes: wayNodes } = way;
const wayNodesSet = new Set(wayNodes);
const curNodeIndex = wayNodes.indexOf(currentNode);
// If not the last way, find a connection point to the next way
// (there should be exactly one)
let nextNode = null;
let nextNodeIndex = null;
if (wayIndex + 1 < ways.length) {
const nextNodeCandidates = elementsById[ways[wayIndex + 1]]
.nodes.filter(node => wayNodesSet.has(node));
if (nextNodeCandidates.length !== 1) {
throw new Error(`There should be exactly one point
connecting way n°${wayIndex} and way n°${wayIndex + 1} in ${name},
but there are ${nextNodeCandidates.length}`);
}
nextNode = nextNodeCandidates[0];
nextNodeIndex = wayNodes.indexOf(nextNode);
} else {
nextNodeIndex = wayNodes.length;
}
if (curNodeIndex < nextNodeIndex) {
// Use the way in its normal direction
path = path.concat(
wayNodes.slice(curNodeIndex, nextNodeIndex)
);
} else {
// Use the way in the reverse direction
if (osm.isOneWay(way)) {
throw new Error(`Way n°${wayIndex} in
${name} is one-way and cannot be used in reverse.`);
}
path = path.concat(
wayNodes.slice(nextNodeIndex + 1, curNodeIndex + 1)
.reverse()
);
}
currentNode = nextNode;
}
// Split the path into segments between stops
for (let stopIdx = 0; stopIdx + 1 < lineStops.length; ++stopIdx) {
const begin = elementsById[lineStops[stopIdx]].tags.ref;
const beginIdx = path.indexOf(lineStops[stopIdx]);
const end = elementsById[lineStops[stopIdx + 1]].tags.ref;
const endIdx = path.indexOf(
lineStops[stopIdx + 1],
beginIdx
) + 1;
const id = `${begin}-${end}`;
const nodesIds = path.slice(beginIdx, endIdx);
if (id in segments) {
if (!util.arraysEqual(
nodesIds,
segments[id].properties.nodesIds
)) {
throw new Error(`Segment ${id} is defined as a
different sequence of nodes in two or more lines.`);
}
segments[id].properties.routes.push([lineRef, routeRef]);
} else {
segments[id] = turfHelpers.lineString(nodesIds.map(
nodeId => [
elementsById[nodeId].lon,
elementsById[nodeId].lat
]
), {
// Keep track of the original sequence of nodes to
// compare with duplicates
nodesIds,
routes: [[lineRef, routeRef]],
begin: begin,
end: end,
}, { id });
segments[id].properties.length = (
1000 * turfLength(segments[id]));
}
}
routes.push({
from,
via,
to,
name,
state
});
}
lines[lineRef] = {
color,
routes
};
}
// Remove OSM nodes from segments that were only used for checking validity
for (const segment of Object.values(segments)) {
delete segment.properties.nodesIds;
}
return { lines, stops, segments };
};
/**
* Create a graph for navigating between stops.
* @param {Array.<Object>} elementsList List of nodes retrieved from OSM.
* @param {Object.<string,Object>} elementsById OSM nodes indexed by their ID.
* @return {Object} Resulting graph and reverse arcs. * @return {Object} Resulting graph and reverse arcs.
*/ */
const createNavigationGraph = (elementsList, elementsById) => { const createNavigationGraph = (elementsList, elementsById) => {
@ -364,7 +126,7 @@ const createNavigationGraph = (elementsList, elementsById) => {
let to = obj.nodes[i + 1].toString(); let to = obj.nodes[i + 1].toString();
let path = [from, to]; let path = [from, to];
// Make sure we cant jump between rails at railway crossings // Make sure we dont switch between rails at railway crossings
if (i + 2 < obj.nodes.length if (i + 2 < obj.nodes.length
&& osm.isRailwayCrossing(elementsById[to])) { && osm.isRailwayCrossing(elementsById[to])) {
const next = obj.nodes[i + 2].toString(); const next = obj.nodes[i + 2].toString();
@ -390,18 +152,17 @@ const createNavigationGraph = (elementsList, elementsById) => {
}; };
/** /**
* Identify intermediate nodes of the navigation graph that can be simplified. * Identify intermediate nodes that can be simplified in a navigation graph.
* @param {Set.<string>} stopsSet OSM IDs of stop nodes. * @param {Set.<string>} keep ID of nodes that must be kept.
* @param {Navigation} navigation Input navigation graph. * @param {Navigation} navigation Input navigation graph.
* @param {Object.<string,Set.<string>>} navigationReverse Reverse arcs. * @param {Object.<string,Set.<string>>} navigationReverse Reverse arcs.
* @return {Set.<string>} Set of compressible nodes. * @return {Set.<string>} Set of compressible nodes.
*/ */
const findCompressibleNodes = (stopsSet, navigation, navigationReverse) => { const findCompressibleNodes = (keep, navigation, navigationReverse) => {
const compressible = new Set(); const compressible = new Set();
for (const nodeId in navigation) { for (const nodeId in navigation) {
if (stopsSet.has(nodeId)) { if (keep.has(nodeId)) {
// Keep stop nodes
continue; continue;
} }
@ -667,14 +428,11 @@ const cleanUpIsolatedNodes = (navigation, navigationReverse) => {
/** /**
* Remove and relink nodes that connect only two nodes or less. * Remove and relink nodes that connect only two nodes or less.
* @param {Object.<string,Stop>} stops List of stops. * @param {Set.<string>} keep ID of nodes that must be kept.
* @param {Navigation} navigation Input navigation graph. * @param {Navigation} navigation Input navigation graph.
* @param {Object.<string,Set.<string>>} navigationReverse Reverse arcs. * @param {Object.<string,Set.<string>>} navigationReverse Reverse arcs.
*/ */
const compressNavigationGraph = (stops, navigation, navigationReverse) => { const compressNavigationGraph = (keep, navigation, navigationReverse) => {
const stopsSet = new Set(
Object.values(stops).map(stop => stop.properties.node)
);
let compressible = null; let compressible = null;
let didCompress = true; let didCompress = true;
@ -683,7 +441,7 @@ const compressNavigationGraph = (stops, navigation, navigationReverse) => {
while (didRemove) { while (didRemove) {
compressible = findCompressibleNodes( compressible = findCompressibleNodes(
stopsSet, navigation, navigationReverse keep, navigation, navigationReverse
); );
didRemove = removeDeadEnds( didRemove = removeDeadEnds(
navigation, navigationReverse, compressible navigation, navigationReverse, compressible
@ -721,24 +479,186 @@ const makeNavigationSegments = (navigation, elementsById) => {
}; };
/** /**
* Fetch information about the network. * Fetch the network of routes that connect the given nodes.
* @param {Array.<string>} lineRefs List of lines to fetch. * @param {Set.<string>} nodes ID of nodes to connect.
* @returns {Network} Network metadata extracted from OSM. * @param {string} type Type of public transport vehicle.
* @param {Bounds} bounds Rectangle bounding the network.
* @return {Navigation} Resulting graph.
*/ */
export const fetch = async lineRefs => { const fetchNavigationGraph = async (nodes, type, bounds) => {
const elementsList = await queryLines(lineRefs); const filter = osm.buildFilter(osm.vehicleWayFilter(type));
const elementsList = (await osm.runQuery(`[out:json];
way${filter}(${bounds});
(._; >;);
out body qt;
`)).elements;
const elementsById = elementsList.reduce((prev, elt) => { const elementsById = elementsList.reduce((prev, elt) => {
prev[elt.id] = elt; prev[elt.id] = elt;
return prev; return prev;
}, {}); }, {});
const { lines, stops, segments } = processRoutes(elementsList, elementsById);
const { navigation, navigationReverse } = createNavigationGraph( const { navigation, navigationReverse } = createNavigationGraph(
elementsList, elementsById elementsList, elementsById
); );
compressNavigationGraph(stops, navigation, navigationReverse); compressNavigationGraph(nodes, navigation, navigationReverse);
makeNavigationSegments(navigation, elementsById); makeNavigationSegments(navigation, elementsById);
return { navigation, lines, stops, segments }; return navigation;
};
/**
* Route of a line of a transport network.
* @typedef {Object} Route
* @property {string} from Name of the starting point of the route.
* @property {string} to Name of the ending point of the route.
* @property {string?} via Optional name of a major intermediate
* stop of the route.
* @property {string} name Human-readable name of the route.
* @property {Array.<string>} stops Sequence of stop IDs along the route.
*/
/**
* Line of a transport network.
* @typedef {Object} Line
* @property {string} color Hexadecimal color code of the line.
* @property {Array.<Route>} routes Routes of the line.
*/
/**
* Find all public transport lines and routes matching a set of criteria.
* @param {string} network Name of the public transport network
* to which the lines must belong.
* @param {string} type Type of public transport vehicle.
* @param {Bounds} bounds Area bounding the public transport network.
* @return {Object.<string,Line>} Assembled information about lines and routes.
*/
const queryLines = async (network, type, bounds) => {
const routeFilter = osm.buildFilter({
type: "route",
route: type,
network,
});
const masterFilter = osm.buildFilter({
type: "route_master",
route_master: type,
network,
});
const elementsList = (await osm.runQuery(`[out:json];
relation${routeFilter}(${bounds});
relation${masterFilter}(br);
(._; >>;);
out body;
`)).elements;
const elementsById = elementsList.reduce((prev, elt) => {
prev[elt.id] = elt;
return prev;
}, {});
const lines = {};
const routeMasters = elementsList.filter(osm.isTransportLine);
// Extract lines, associated stops and planned routes
for (const routeMaster of routeMasters) {
const lineRef = routeMaster.tags.ref;
const color = routeMaster.tags.colour.toUpperCase() || "#000000";
const routes = [];
for (const [routeRef, data] of routeMaster.members.entries()) {
const routeId = data.ref;
const route = elementsById[routeId];
const { from, via, to, name } = route.tags;
// Check that the route consists of a block of stops and platforms
// followed by a block of routes as dictated by PTv2
const relationPivot = route.members.findIndex(
({ role }) => role === ""
);
if (!route.members.slice(0, relationPivot).every(
({ role }) => osm.isInitialRouteRole(role)
)) {
throw new Error(`Members with invalid roles in between stops \
of ${name}`);
}
if (!route.members.slice(relationPivot).every(
({ role }) => role === ""
)) {
throw new Error(`Members with invalid roles inside the path \
of ${name}`);
}
// List of stops in the route, expected to be in the timetable
// order as per PTv2
const stops = route.members.slice(0, relationPivot)
.filter(({ role }) => role === "stop")
.map(({ ref }) => elementsById[ref].tags.ref);
routes.push({
from,
...(via && { via }),
to,
name,
stops,
});
}
lines[lineRef] = {
color,
routes
};
}
return lines;
};
/**
* Record which lines use which stops.
* @param {Object.<string,Stop>} stops List of stops.
* @param {Object.<string,Line>} lines List of lines.
*/
const recordStops = (stops, lines) => {
for (const [lineRef, line] of Object.entries(lines)) {
for (const [routeRef, route] of line.routes.entries()) {
for (const stop of route.stops) {
const routes = stops[stop].properties.routes;
if (routes.findIndex(([testLineRef, testRouteRef]) =>
lineRef === testLineRef && routeRef === testRouteRef
) === -1) {
routes.push([lineRef, routeRef]);
}
}
}
}
};
/**
* Information about a public transport network.
* @typedef {Object} Network
* @property {Object.<string,Stop>} stops List of stops.
* @property {Object.<string,Line>} lines List of lines.
* @property {Object.<string,Segment>} segments List of segments.
* @property {Navigation} navigation Graph for navigating between stops.
*/
/**
* Fetch information about a public transport network.
* @param {string} network Name of the public transport network.
* @param {string} type Type of public transport vehicle.
* @param {Bounds} bounds Area bounding the public transport network.
* @returns {Network} Network metadata extracted from OSM.
*/
export const fetch = async (network, type, bounds) => {
const stops = await fetchStops(network, type, bounds);
const stopIds = new Set(
Object.values(stops).map(stop => stop.properties.node)
);
const navigation = await fetchNavigationGraph(stopIds, type, bounds);
const lines = await queryLines(network, type, bounds);
recordStops(stops, lines);
return { navigation, stops, lines };
}; };

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@ -7,10 +7,65 @@
import axios from "axios"; import axios from "axios";
import { isObject } from "../../util.js"; import { isObject } from "../../util.js";
/** Replace a value for use in an Overpass query. */
export const escape = value =>
value.replace("'", "\\'").replace('"', '\\"').replace("\\", "\\\\");
/**
* Transform a set of tag queries into an Overpass set of filters.
*
* @param {Object} tags A set of tag queries.
* @return {string} Corresponding Overpass filter.
*/
export const buildFilter = tags => Object.entries(tags).filter(
([key, value]) => {
return value !== undefined && value !== null;
}
).map(
([key, value]) => {
if (value === true) {
return `[${key}]`;
}
if (value === false) {
return `[!${key}]`;
}
if (value === "") {
// See <https://github.com/drolbr/Overpass-API/issues/92>
return `[${key}~"^$"]`;
}
return `[${key}="${escape(value)}"]`
}
).join("");
/**
* Get the appropriate tag query for matching ways that can be used by a given
* public transport vehicle.
* @param {string} type Type of public transport vehicle.
* @return {Object} Set of tag queries.
*/
export const vehicleWayFilter = type => {
switch (type) {
case "bus":
return {highway: true};
case "train":
case "subway":
case "light_rail":
case "tram":
return {railway: type};
default:
throw new Error(`Unknown vehicle type: ${type}`);
}
};
/** /**
* Submit a query to an Overpass endpoint. * Submit a query to an Overpass endpoint.
* *
* See <https://wiki.osm.org/Overpass_API/Overpass_QL> for more * @see <https://wiki.osm.org/Overpass_API/Overpass_QL> for more
* information on the Overpass Query Language (Overpass QL). * information on the Overpass Query Language (Overpass QL).
* @async * @async
* @param {string} query Query to send. * @param {string} query Query to send.
@ -22,10 +77,11 @@ import { isObject } from "../../util.js";
export const runQuery = ( export const runQuery = (
query, query,
endpoint = "https://lz4.overpass-api.de/api/interpreter" endpoint = "https://lz4.overpass-api.de/api/interpreter"
) => ( ) => {
axios.post(endpoint, `data=${query}`) console.log("Running query:", query);
.then(res => res.data) return axios.post(endpoint, `data=${query}`)
); .then(res => res.data);
};
/** /**
* Create a link to view a node. * Create a link to view a node.
@ -37,7 +93,7 @@ export const viewNode = id => `https://www.osm.org/node/${id}`;
/** /**
* Determine if an OSM way is one-way or not. * Determine if an OSM way is one-way or not.
* *
* See <https://wiki.osm.org/Key:oneway> for details. * @see <https://wiki.osm.org/Key:oneway>
* @param {Object} obj OSM way object. * @param {Object} obj OSM way object.
* @returns {boolean} Whether the way is one-way. * @returns {boolean} Whether the way is one-way.
*/ */
@ -51,7 +107,7 @@ export const isOneWay = obj => (
/** /**
* Determine if a node is a railway crossing or not. * Determine if a node is a railway crossing or not.
* *
* See <https://wiki.osm.org/Tag:railway=railway_crossing> for details. * @see <https://wiki.osm.org/Tag:railway=railway_crossing>
* @param {Object} obj OSM node object. * @param {Object} obj OSM node object.
* @return {boolean} Whether the node is a railway crossing. * @return {boolean} Whether the node is a railway crossing.
*/ */
@ -64,8 +120,8 @@ export const isRailwayCrossing = obj => (
/** /**
* Determine if an OSM object is a public transport line (route master). * Determine if an OSM object is a public transport line (route master).
* *
* See <https://wiki.osm.org/Relation:route_master> * @see <https://wiki.osm.org/Relation:route_master>
* and <https://wiki.osm.org/Public_transport#Route_Master_relations>. * @see <https://wiki.osm.org/Public_transport#Route_Master_relations>
* @param {Object} obj OSM relation object. * @param {Object} obj OSM relation object.
* @returns {boolean} Whether the relation is a public transport line. * @returns {boolean} Whether the relation is a public transport line.
*/ */
@ -74,3 +130,17 @@ export const isTransportLine = obj => (
isObject(obj.tags) && isObject(obj.tags) &&
obj.tags.type === "route_master" obj.tags.type === "route_master"
); );
/**
* Determine if a public transport route member has a valid role for
* the initial segment of stops and platforms according to PTv2.
*
* @see <https://wiki.openstreetmap.org/wiki/Public_transport#Service_routes>
* @param {string} role Role to check.
* @returns {boolean} Whether the role is valid.
*/
export const isInitialRouteRole = role => (
role === "stop" || role === "stop_entry_only" || role === "stop_exit_only"
|| role === "platform" || role === "platform_entry_only"
|| role === "platform_exit_only"
);