implement basic express server + api

backend/src/api.js

@@ -0,0 +1,77 @@
+import { Router } from "express";
+
+const router = Router();
+
+router.get("/healthcheck", (req, res) => {
+    res.json({ status: "ok" })
+});
+
+router.post("/scores", async (req, res) => {
+    const { name, game, score } = req.body;
+
+    if (!name || !game || !Number.isFinite(score) || !Number.isInteger(score) || score < 0) {
+        return res.status(400).json({ error: "Missing or invalid parameters" });
+    }
+
+    const conn = await pool.getConnection();
+
+    try {
+        await conn.beginTransaction();
+
+        const [userRows] = await conn.query(
+            `INSERT INTO users (name) VALUES (?)`,
+            [name]
+        );
+        const userId = userRows.insertId;
+
+        const [gameRows] = await conn.query(
+            `INSERT INTO games (name) VALUES (?) ON DUPLICATE KEY UPDATE id=LAST_INSERT_ID(id)`,
+            [game]
+        );
+        const gameId = gameRows.insertId;
+
+        await conn.query(
+            `
+            INSERT INTO scores (user_id, game_id, score)
+            VALUES (?, ?, ?)
+            ON DUPLICATE KEY UPDATE score = GREATEST(score, VALUES(score))
+            `,
+            [userId, gameId, score]
+        );
+
+        await conn.commit();
+        res.json({ success: true });
+    } catch (err) {
+        await conn.rollback();
+        console.error(err);
+        res.status(500).json({ error: "Database error" });
+    } finally {
+        conn.release();
+    }
+});
+
+router.get("/leaderboard/:game", async (req, res) => {
+    const gameName = req.params.game;
+
+    try {
+        const [rows] = await pool.query(
+            `
+            SELECT u.name AS user, s.score, s.created_at
+            FROM scores s
+            JOIN users u ON s.user_id = u.id
+            JOIN games g ON s.game_id = g.id
+            WHERE g.name = ?
+            ORDER BY s.score DESC, s.created_at ASC
+            LIMIT 10
+            `,
+            [gameName]
+        );
+
+        res.json({ leaderboard: rows });
+    } catch (err) {
+        console.error(err);
+        res.status(500).json({ error: "Database error" });
+    }
+});
+
+export default router;

backend/src/index.js

@@ -1,5 +1,22 @@
 import dotenv from 'dotenv';
+import express from 'express';
+import path from 'path';
+import { fileURLToPath } from 'url';
+import apiRouter from './api.js';
 dotenv.config();
-const db = await import('./db.js');
 
-db.initDB();
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.join(path.dirname(__filename), ".."); // going back a dir cuz code is in src/
+const db = await import('./db.js'); // dynamic import because otherwise dotenv will not work correctly
+const app = express();
+
+db.initDB();
+
+app.use(express.static(path.join(__dirname, "public"), {
+  dotfiles: "ignore"
+}));
+app.use("/api", apiRouter);
+
+const server = app.listen(0, () => {
+  console.log(`Server running on http://localhost:${server.address().port}`);
+});