Split data/endpoints.js into osm and tam

back/data/network.js

@@ -1,30 +1,20 @@
 /**
  * @file
+ *
  * Extract static information about the TaM network from OpenStreetMap (OSM):
  * tram and bus lines, stops and routes.
  *
  * Functions in this file also report and offer to correct errors that may
  * occur in OSM data.
+ *
+ * Because of the static nature of this data, it is cached in a
+ * version-controlled file `network.json` next to this file. To update it, use
+ * the `script/update-network` script.
  */
 
 const {choosePlural, joinSentence} = require('../util');
-const {queryOverpass, fetchTamTheoretical} = require('./endpoints');
+const osm = require('./sources/osm');
-
+const tam = require('./sources/tam');
-const osmViewNode = 'https://www.openstreetmap.org/node';
-
-/**
- * Create a link to add tags into JOSM.
- *
- * @param objectId Identifier for the object to add the tags to.
- * @param tags Tags to add.
- * @return Link for remotely adding the tags.
- */
-const josmAddTagToNode = (objectId, tags) =>
-    'http://127.0.0.1:8111/load_object?' + [
-        `objects=n${objectId}`,
-        'new_layer=false',
-        'addtags=' + tags.join('%7C'),
-    ].join('&');
 
 /**
  * Use theoretical passings data to guess which lines use which stops in which
@@ -40,7 +30,7 @@ const fetchStopsRefAssociations = () => new Promise((res, rej) =>
 {
     const stops = {};
 
-    fetchTamTheoretical((err, row) =>
+    tam.fetchTheoretical((err, row) =>
     {
         if (err)
         {
@@ -131,17 +121,6 @@ const matchStopNames = (fullName, abbrName) =>
     ).length;
 };
 
-/**
- * Determine if an OSM way is oneway or not.
- *
- * @param tags Set of tags of the way.
- * @return True iff. the way is oneway.
- */
-const isOneWay = tags =>
-    ('oneway' in tags && tags.oneway === 'yes')
-    || ('junction' in tags && tags.junction === 'roundabout')
-    || ('highway' in tags && tags.highway === 'motorway');
-
 /**
  * Fetch stops and lines of the network.
  *
@@ -151,7 +130,7 @@ const isOneWay = tags =>
 const fetch = async (lineRefs) =>
 {
     // Retrieve routes, ways and stops from OpenStreetMap
-    const rawData = await queryOverpass(`[out:json];
+    const rawData = await osm.runQuery(`[out:json];
 
 // Find the public transport line bearing the requested reference
 relation[network="TaM"][type="route_master"][ref~"^(${lineRefs.join('|')})$"];
@@ -169,9 +148,7 @@ out body qt;
     const elementsList = rawData.elements;
 
     // List of retrieved lines
-    const routeMasters = elementsList.filter(elt =>
+    const routeMasters = elementsList.filter(osm.isTransportLine);
-        elt.tags && elt.tags.type === 'route_master'
-    );
 
     // Retrieved objects indexed by ID
     const elements = elementsList.reduce((prev, elt) =>
@@ -208,7 +185,7 @@ out body qt;
                         console.warn(`Stop ${stop.id} is missing a “ref” tag
 Name: ${stop.tags.name}
 Part of line: ${route.tags.name}
-URI: ${osmViewNode}/${stop.id}
+URI: ${osm.viewNode(stop.id)}
 `);
 
                         // Try to identify stops matching this stop in the
@@ -262,7 +239,7 @@ URI: ${osmViewNode}/${stop.id}
 ${choosePlural(candidate.lines.length, 'line', '.s')} \
 ${joinSentence(Array.from(candidate.lines), ', ', ' and ')} going to \
 ${joinSentence(Array.from(candidate.directions), ', ', ' or ')}
-      Apply in JOSM: ${josmAddTagToNode(stop.id, ['ref=' + candidate.stopRef])}
+      Apply in JOSM: ${osm.addTagsToNode(stop.id, ['ref=' + candidate.stopRef])}
 `);
                             }
                         }
@@ -292,11 +269,7 @@ ${joinSentence(Array.from(candidate.directions), ', ', ' or ')}
 
         for (let route of rawRoutes)
         {
-            const {from, to} = route.tags;
+            const {from, to, name} = route.tags;
-
-            // Human-readable description of the route for errors
-            const routeDescription = `line ${lineRef}’s route from \
-“${route.tags.from}” to “${route.tags.to}”`;
 
             // Check that the route consists of a block of stops and platforms
             // followed by a block of routes as dictated by PTv2
@@ -309,7 +282,7 @@ ${joinSentence(Array.from(candidate.directions), ', ', ' or ')}
             ))
             {
                 throw new Error(`Members with invalid roles in between stops
-of ${routeDescription}`);
+of ${name}`);
             }
 
             if (!route.members.slice(relationPivot).every(
@@ -317,7 +290,7 @@ of ${routeDescription}`);
             ))
             {
                 throw new Error(`Members with invalid roles inside the path
-of ${routeDescription}`);
+of ${name}`);
             }
 
             // List of stops in the route, expected to be in the timetable
@@ -338,8 +311,8 @@ of ${routeDescription}`);
 
             for (let wayIndex = 0; wayIndex < ways.length; wayIndex += 1)
             {
-                const {nodes: wayNodes, tags: wayTags}
+                const way = elements[ways[wayIndex]];
-                    = elements[ways[wayIndex]];
+                const {nodes: wayNodes, tags: wayTags} = way;
                 const wayNodesSet = new Set(wayNodes);
 
                 const curNodeIndex = wayNodes.indexOf(currentNode);
@@ -357,7 +330,7 @@ of ${routeDescription}`);
                     if (nextNodeCandidates.length !== 1)
                     {
                         throw new Error(`There should be exactly one point
-connecting way n°${wayIndex} and way n°${wayIndex + 1} in ${routeDescription},
+connecting way n°${wayIndex} and way n°${wayIndex + 1} in ${name},
 but there are ${nextNodeCandidates.length}`);
                     }
 
@@ -379,10 +352,10 @@ but there are ${nextNodeCandidates.length}`);
                 else
                 {
                     // Use the way in the reverse direction
-                    if (isOneWay(wayTags))
+                    if (osm.isOneWay(way))
                     {
                         throw new Error(`Way n°${wayIndex} in
-${routeDescription} is one-way and cannot be used in reverse.`);
+${name} is one-way and cannot be used in reverse.`);
                     }
 
                     path = path.concat(
@@ -409,8 +382,7 @@ ${routeDescription} is one-way and cannot be used in reverse.`);
             }
 
             routes.push({
-                from, to,
+                from, to, name,
-                name: route.tags.name,
                 segments,
                 stops: stops.map(id => elements[id].tags.ref),
             });

back/data/sources/osm.js

@@ -0,0 +1,89 @@
+/**
+ * @file
+ *
+ * Interface with the OpenStreetMap collaborative mapping database.
+ */
+
+const axios = require('axios');
+const {isObject} = require('../../util');
+
+/**
+ * Submit a query to an Overpass endpoint.
+ *
+ * See <https://wiki.openstreetmap.org/wiki/Overpass_API/Overpass_QL> for more
+ * information on the Overpass Query Language (Overpass QL).
+ *
+ * @async
+ * @param query Query to send.
+ * @param [endpoint] Overpass endpoint to use.
+ * @return Results returned by the endpoint. If JSON output is requested in
+ * the query, the result will automatically be parsed into a JS object.
+ */
+const runQuery = (
+    query,
+    endpoint = 'https://lz4.overpass-api.de/api/interpreter'
+) => axios.post(endpoint, 'data=' + query)
+    .then(res => res.data);
+
+exports.runQuery = runQuery;
+
+/**
+ * Create a link to add tags into JOSM.
+ *
+ * The JOSM remote control must be activated and JOSM must be running for this
+ * link to work. See <https://wiki.openstreetmap.org/wiki/JOSM/RemoteControl>.
+ *
+ * @param id Identifier for the object to add the tags to.
+ * @param tags List of tags to add, in the `key=value` format.
+ * @return Link for remotely adding the tags.
+ */
+const addTagsToNode = (id, tags) =>
+    'http://127.0.0.1:8111/load_object?' + [
+        `objects=n${id}`,
+        'new_layer=false',
+        'addtags=' + tags.join('%7C'),
+    ].join('&');
+
+exports.addTagsToNode = addTagsToNode;
+
+/**
+ * Create a link to view a node.
+ *
+ * @param id Identifier for the node to view.
+ * @return Link to view this node on the OSM website.
+ */
+const viewNode = id => `https://www.openstreetmap.org/node/${id}`;
+
+exports.viewNode = viewNode;
+
+/**
+ * Determine if an OSM way is one-way or not.
+ *
+ * See <https://wiki.openstreetmap.org/wiki/Key:oneway> for details.
+ *
+ * @param tags Set of tags of the way.
+ * @return True iff. the way is one-way.
+ */
+const isOneWay = object =>
+    object.type === 'way'
+    && isObject(object.tags)
+    && (object.tags.oneway === 'yes' || object.tags.junction === 'roundabout'
+        || object.tags.highway === 'motorway');
+
+exports.isOneWay = isOneWay;
+
+/**
+ * Determine if an OSM object is a public transport line (route master).
+ *
+ * See <https://wiki.openstreetmap.org/wiki/Relation:route_master>
+ * and <https://wiki.openstreetmap.org/wiki/Public_transport#Route_Master_relations>.
+ *
+ * @param object OSM object.
+ * @return True iff. the relation is a public transport line.
+ */
+const isTransportLine = object =>
+    object.type === 'relation'
+    && isObject(object.tags)
+    && object.tags.type === 'route_master';
+
+exports.isTransportLine = isTransportLine;

back/data/sources/tam.js

@@ -2,28 +2,12 @@ const unzip = require('unzip-stream');
 const csv = require('csv-parse');
 const axios = require('axios');
 
-const overpassEndpoint = 'https://lz4.overpass-api.de/api/interpreter';
-
-/**
- * Submit an Overpass query.
- *
- * @async
- * @param query Query in Overpass QL.
- * @return Results as provided by the endpoint.
- */
-const queryOverpass = query => axios.post(
-    overpassEndpoint,
-    'data=' + query
-).then(res => res.data);
-
-exports.queryOverpass = queryOverpass;
-
 /**
  * Process a CSV stream to extract passings.
  *
  * @private
  * @param csvStream Stream containing CSV data.
- * @param callback See fetchTamRealtime for a description of the callback.
+ * @param callback See fetchRealtime for a description of the callback.
  */
 const processTamPassingStream = (csvStream, callback) =>
 {
@@ -74,14 +58,14 @@ const tamRealtimeEndpoint = 'http://data.montpellier3m.fr/node/10732/download';
  * be non-null only if an error occurred. Second argument will contain passings
  * or be null if the end was reached.
  */
-const fetchTamRealtime = (callback) =>
+const fetchRealtime = (callback) =>
 {
     axios.get(tamRealtimeEndpoint, {
         responseType: 'stream'
     }).then(res => processTamPassingStream(res.data, callback));
 };
 
-exports.fetchTamRealtime = fetchTamRealtime;
+exports.fetchRealtime = fetchRealtime;
 
 const tamTheoreticalEndpoint =
     'http://data.montpellier3m.fr/node/10731/download';
@@ -94,7 +78,7 @@ const tamTheoreticalFileName = 'offre_du_jour.csv';
  * be non-null only if an error occurred. Second argument will contain passings
  * or be null if the end was reached.
  */
-const fetchTamTheoretical = (callback) =>
+const fetchTheoretical = (callback) =>
 {
     axios.get(tamTheoreticalEndpoint, {
         responseType: 'stream'
@@ -117,4 +101,4 @@ const fetchTamTheoretical = (callback) =>
     });
 };
 
-exports.fetchTamTheoretical = fetchTamTheoretical;
+exports.fetchTheoretical = fetchTheoretical;

back/util.js

@@ -58,3 +58,13 @@ const joinSentence = (array, separator, lastSeparator) =>
 };
 
 exports.joinSentence = joinSentence;
+
+/**
+ * Check if a value is a JS object.
+ *
+ * @param value Value to check.
+ * @return True iff. `value` is a JS object.
+ */
+const isObject = value => value !== null && typeof value === 'object';
+
+exports.isObject = isObject;