Init Discord OAuth2

app/server.js

@@ -0,0 +1,83 @@
+require("dotenv").config(); // charge les variables depuis .env
+
+const express = require("express");
+const session = require("express-session");
+const fetch = require("cross-fetch"); // fetch compatible Node
+const path = require("path");
+
+const app = express();
+const PORT = process.env.PORT || 3000;
+
+const CLIENT_ID = process.env.CLIENT_ID;
+const CLIENT_SECRET = process.env.CLIENT_SECRET;
+const REDIRECT_URI = process.env.REDIRECT_URI;
+
+// --- Session setup ---
+app.use(session({
+  secret: "un_secret_long_et_complexe", // change-le en production
+  resave: false,
+  saveUninitialized: true,
+}));
+
+// --- Servir le dossier public ---
+app.use(express.static(path.join(__dirname, "public")));
+
+// --- Route pour démarrer la connexion Discord ---
+app.get("/auth/discord", (req, res) => {
+  const url = `https://discord.com/api/oauth2/authorize?client_id=${CLIENT_ID}&redirect_uri=${encodeURIComponent(REDIRECT_URI)}&response_type=code&scope=identify`;
+  res.redirect(url);
+});
+
+// --- Callback après connexion Discord ---
+app.get("/auth/discord/callback", async (req, res) => {
+  const code = req.query.code;
+  if (!code) return res.send("Pas de code OAuth reçu !");
+
+  try {
+    // Échange du code contre access token
+    const data = new URLSearchParams();
+    data.append("client_id", CLIENT_ID);
+    data.append("client_secret", CLIENT_SECRET);
+    data.append("grant_type", "authorization_code");
+    data.append("code", code);
+    data.append("redirect_uri", REDIRECT_URI);
+    data.append("scope", "identify");
+
+    const tokenResponse = await fetch("https://discord.com/api/oauth2/token", {
+      method: "POST",
+      body: data,
+      headers: { "Content-Type": "application/x-www-form-urlencoded" },
+    });
+
+    const tokenJson = await tokenResponse.json();
+    const accessToken = tokenJson.access_token;
+
+    // Récupération des infos utilisateur
+    const userResponse = await fetch("https://discord.com/api/users/@me", {
+      headers: { Authorization: `Bearer ${accessToken}` },
+    });
+
+    const user = await userResponse.json();
+
+    // Stocker l'utilisateur dans la session
+    req.session.user = user;
+
+    // Rediriger vers la page HTML
+    res.redirect("/welcome.html");
+  } catch (err) {
+    console.error(err);
+    res.send("Erreur lors de la connexion Discord !");
+  }
+});
+
+// --- API pour récupérer l'objet user côté front ---
+app.get("/api/user", (req, res) => {
+  if (req.session.user) {
+    res.json(req.session.user);
+  } else {
+    res.status(401).json({ error: "Utilisateur non connecté" });
+  }
+});
+
+// --- Lancement du serveur ---
+app.listen(PORT, () => console.log(`Serveur lancé sur http://localhost:${PORT}`));