Add show-courses script

This commit is contained in:
Mattéo Delabre 2021-05-11 17:20:12 +02:00
parent ef6b4b9741
commit 6b7333c46b
Signed by: matteo
GPG Key ID: AE3FBD02DC583ABB
6 changed files with 225 additions and 104 deletions

89
script/show-courses Executable file
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@ -0,0 +1,89 @@
#!/usr/bin/env node
const courses = require('../src/tam/courses');
const network = require('../src/tam/network.json');
const {displayTime} = require('../src/util');
const process = require('process');
const path = require('path');
/**
* Convert stop ID to human-readable stop name.
*
* If the stop ID is not known, the ID will be kept as-is.
*/
const getStopName = stopId =>
{
if (stopId in network.stops)
{
return network.stops[stopId].properties.name;
}
return stopId;
};
/** Create a string representing a course for printing. */
const courseToString = course =>
{
let result = `Course #${course.id}
Line ${course.line} - Direction ${course.direction} - Bound for ${getStopName(course.finalStopId)}
Next stops:
`;
for (let [stopId, time] of course.passings)
{
result += `${displayTime(new Date(time))} - ${getStopName(stopId)}\n`;
}
return result;
};
/** Show user help. */
const doHelp = () =>
{
const name = "./" + path.relative(process.cwd(), process.argv[1]);
process.stdout.write(`Usage: ${name} TYPE [COURSE]
Show TaM courses data.
Set TYPE to 'realtime' to fetch real-time data (limited time scope) or to
'theoretical' to fetch planned courses for the day.
Set COURSE to a valid course ID to limit the output to a given course.
`);
};
/** Print realtime information for a course or all courses. */
const doPrint = async (kind, courseId) =>
{
const results = await courses.fetch(kind);
if (courseId)
{
if (courseId in results)
{
console.log(courseToString(results[courseId]));
}
else
{
console.log('Unknown course');
}
}
else
{
for (let course of Object.values(results))
{
console.log(courseToString(course));
console.log("======\n");
}
}
};
const argv = process.argv.slice(2);
if (argv.length === 0)
{
doHelp();
process.exit(1);
}
doPrint(argv[0], argv[1]);

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@ -1,12 +1,12 @@
const express = require("express"); const express = require("express");
const realtime = require("../tam/realtime"); const courses = require("../tam/courses");
const app = express(); const app = express();
const port = 4321; const port = 4321;
app.get("/courses", async(req, res) => { app.get("/courses", async(req, res) => {
res.header("Access-Control-Allow-Origin", "*"); res.header("Access-Control-Allow-Origin", "*");
return res.json(await realtime.fetch()); return res.json(await courses.fetch("realtime"));
}); });
app.listen(port, () => console.info(`App listening on port ${port}`)); app.listen(port, () => console.info(`App listening on port ${port}`));

123
src/tam/courses.js Normal file
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const path = require("path");
const fs = require("fs").promises;
const tam = require("./sources/tam");
const network = require("./network.json");
/**
* Information about the course of a vehicle.
* @typedef {Object} Course
* @property {string} id Unique identifier for this course.
* @property {string} line Transport line number.
* @property {string} finalStop Final stop to which the course is headed.
* @property {Array.<Array>} passings Next stations to which
* the vehicle will stop, associated to the passing timestamp, ordered by
* increasing passing timestamp.
*/
/** Parse time information relative to the current date. */
const parseTime = (time, reference) =>
{
const [hours, minutes, seconds] = time.split(':').map(x => parseInt(x, 10));
const result = new Date(reference);
result.setHours(hours);
result.setMinutes(minutes);
result.setSeconds(seconds);
if (reference > result.getTime()) {
// Timestamps in the past refer to the next day
result.setDate(result.getDate() + 1);
}
return result;
};
/**
* Fetch information about courses in the TaM network.
*
* @param {string} kind Pass 'realtime' to get real-time information,
* or 'theoretical' to get planned courses for the day.
* @returns {Object.<string,Course>} Mapping from active course IDs to
* information about each course.
*/
const fetch = async (kind = 'realtime') => {
const courses = {};
const passings = (
kind === 'realtime'
? tam.fetchRealtime()
: tam.fetchTheoretical()
);
const timing = (await passings.next()).value;
// Aggregate passings relative to the same course
for await (const passing of passings) {
const {
course: id,
routeShortName: line,
stopId,
destArCode: finalStopId,
} = passing;
const direction = (
'direction' in passing
? passing.direction
: passing.directionId
);
const departureTime = (
'delaySec' in passing
? timing.lastUpdate + parseInt(passing.delaySec, 10) * 1000
: parseTime(passing.departureTime, timing.lastUpdate)
);
if (!(id in courses)) {
courses[id] = {
id,
line,
direction,
finalStopId,
passings: {},
};
}
if (!(stopId in courses[id].passings) ||
courses[id].passings[stopId] < departureTime) {
// Only consider passings with an increased passing time
// or for stops not seen before
courses[id].passings[stopId] = departureTime;
}
}
// Filter courses to only keep those referring to known data
for (const courseId of Object.keys(courses)) {
const course = courses[courseId];
if (!(course.line in network.lines)) {
delete courses[courseId];
} else {
for (const stopId of Object.keys(course.passings)) {
if (!(stopId in network.stops)) {
delete courses[courseId];
break;
}
}
}
}
// Order next passings by increasing passing time
for (const course of Object.values(courses)) {
course.passings = (
Object.entries(course.passings).sort(
([, time1], [, time2]) => time1 - time2
)
);
if (course.finalStopId === undefined) {
course.finalStopId = course.passings[course.passings.length - 1][0];
}
}
return courses;
};
exports.fetch = fetch;

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@ -1,100 +0,0 @@
const tam = require("./sources/tam");
const network = require("./network.json");
// Time at which the course data needs to be updated next
let nextUpdate = null;
// Current information about courses
let currentCourses = null;
/**
* Information about the course of a vehicle.
* @typedef {Object} Course
* @property {string} id Unique identifier for this course.
* @property {string} line Transport line number.
* @property {string} finalStop Final stop to which the course is headed.
* @property {Array.<Array>} nextPassings Next stations to which
* the vehicle will stop, associated to the passing timestamp, ordered by
* increasing passing timestamp.
*/
/**
* Fetch real-time information about active courses in the TaM network.
*
* New data will only be fetched from the TaM server once every minute,
* otherwise pulling from the in-memory cache.
* @returns {Object.<string,Course>} Mapping from active course IDs to
* information about each course.
*/
const fetch = async() => {
if (nextUpdate === null || Date.now() >= nextUpdate) {
const courses = {};
const passings = tam.fetchRealtime();
const timing = (await passings.next()).value;
nextUpdate = timing.nextUpdate;
// Aggregate passings relative to the same course
for await (const passing of passings) {
const {
course: id,
routeShortName: line,
stopId,
destArCode: finalStop
} = passing;
const arrivalTime = (
timing.lastUpdate +
parseInt(passing.delaySec, 10) * 1000
);
if (!(id in courses)) {
courses[id] = {
id,
line,
finalStop,
// Initially accumulate passings in an object
// to prevent duplicates
nextPassings: { [stopId]: arrivalTime }
};
} else if (!(stopId in courses[id].nextPassings) ||
courses[id].nextPassings[stopId] < arrivalTime) {
// Only consider passings with an increased passing time
// or for stops not seen before
courses[id].nextPassings[stopId] = arrivalTime;
}
}
// Filter courses to only keep those referring to known data
for (const courseId of Object.keys(courses)) {
const course = courses[courseId];
if (!(course.line in network.lines)) {
delete courses[courseId];
} else {
for (const stopId of Object.keys(course.nextPassings)) {
if (!(stopId in network.stops)) {
delete courses[courseId];
break;
}
}
}
}
// Order next passings by increasing passing time
for (const courseId of Object.keys(courses)) {
courses[courseId].nextPassings = (
Object.entries(courses[courseId].nextPassings).sort(
([, time1], [, time2]) => time1 - time2
)
);
}
currentCourses = courses;
}
return currentCourses;
};
exports.fetch = fetch;

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@ -59,8 +59,9 @@ class Course {
updateData(data) { updateData(data) {
this.line = data.line; this.line = data.line;
this.finalStop = data.finalStop; this.direction = data.direction;
this.nextPassings = data.nextPassings; this.finalStop = data.finalStopId;
this.nextPassings = data.passings;
const now = Date.now(); const now = Date.now();

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@ -63,3 +63,11 @@ const unzipFile = (data, fileName) => new Promise((res, rej) => {
}); });
exports.unzipFile = unzipFile; exports.unzipFile = unzipFile;
const displayTime = date => [
date.getHours(),
date.getMinutes(),
date.getSeconds()
].map(number => number.toString().padStart(2, "0")).join(":");
exports.displayTime = displayTime;