feat: Building the app in it's first version

server.js

@@ -0,0 +1,66 @@
+'use strict';
+
+const path = require('path');
+const express = require('express');
+const { gregorianToRepublican } = require('./src/republicanCalendar');
+
+const app = express();
+const port = process.env.PORT || 3000;
+
+app.use(express.static(path.join(__dirname, 'public')));
+app.use('/locales', express.static(path.join(__dirname, 'locales')));
+
+function nowUtc() {
+  const now = new Date();
+  return {
+    year: now.getUTCFullYear(),
+    month: now.getUTCMonth() + 1,
+    day: now.getUTCDate(),
+  };
+}
+
+function convertAndRespond(res, gregorianDate) {
+  try {
+    const republicanDate = gregorianToRepublican(gregorianDate);
+    res.json({ ok: true, republicanDate });
+  } catch (error) {
+    if (error.message === 'BEFORE_EPOCH') {
+      res.status(400).json({
+        ok: false,
+        error: 'BEFORE_EPOCH',
+        message: 'The Republican calendar begins on 22 September 1792.',
+      });
+      return;
+    }
+    res.status(400).json({
+      ok: false,
+      error: 'INVALID_DATE',
+      message: 'The given date does not exist in the Gregorian calendar.',
+    });
+  }
+}
+
+app.get('/api/today', (req, res) => {
+  convertAndRespond(res, nowUtc());
+});
+
+app.get('/api/convert', (req, res) => {
+  const year = Number.parseInt(req.query.year, 10);
+  const month = Number.parseInt(req.query.month, 10);
+  const day = Number.parseInt(req.query.day, 10);
+
+  if (!Number.isInteger(year) || !Number.isInteger(month) || !Number.isInteger(day)) {
+    res.status(400).json({
+      ok: false,
+      error: 'INVALID_DATE',
+      message: 'year, month and day query parameters are required integers.',
+    });
+    return;
+  }
+
+  convertAndRespond(res, { year, month, day });
+});
+
+app.listen(port, () => {
+  console.log(`Calendrier republicain server listening on port ${port}`);
+});