initial commit

src/db.ts

@@ -0,0 +1,22 @@
+import { Pool } from 'pg';
+import dotenv from 'dotenv';
+
+dotenv.config();
+
+export const pgPool = new Pool({
+  host: process.env.POSTGRES_HOST,
+  port: Number(process.env.POSTGRES_PORT || 5432),
+  database: process.env.POSTGRES_DB,
+  user: process.env.POSTGRES_USER,
+  password: process.env.POSTGRES_PASSWORD,
+});
+
+export async function initDb(): Promise<void> {
+  await pgPool.query(`
+    CREATE TABLE IF NOT EXISTS motd (
+      id SERIAL PRIMARY KEY,
+      message TEXT NOT NULL,
+      created_at TIMESTAMP NOT NULL DEFAULT NOW()
+    )
+  `);
+}

src/http/motd.ts

@@ -0,0 +1,85 @@
+import { Express } from 'express';
+import { redisClient } from '../index.js';
+import { pgPool } from '../db.js';
+
+
+export async function httpMotd(app: Express) {
+
+  app.get('/motd', async (_req, res) => {
+    try {
+      const cached = await redisClient.get('motd:current');
+      if (cached) {
+        return res.json({
+          source: 'redis',
+          message: cached,
+        });
+      }
+
+      const result = await pgPool.query(
+        `
+        SELECT message
+        FROM motd
+        ORDER BY created_at DESC, id DESC
+        LIMIT 1
+        `
+      );
+
+      if (result.rowCount === 0) {
+        return res.status(404).json({
+          error: 'No MOTD set',
+        });
+      }
+
+      const message = result.rows[0].message as string;
+      await redisClient.set('motd:current', message, {
+        EX: 60,
+      });
+
+      return res.json({
+        source: 'postgres',
+        message,
+      });
+    } catch (error) {
+      console.error(error);
+      return res.status(500).json({
+        error: 'Internal server error',
+      });
+    }
+  });
+
+  app.post('/motd', async (req, res) => {
+    try {
+      const message = req.body?.message;
+
+      if (typeof message !== 'string' || message.trim() === '') {
+        return res.status(400).json({
+          error: 'message must be a non-empty string',
+        });
+      }
+
+      const trimmedMessage = message.trim();
+
+      await pgPool.query(
+        `
+        INSERT INTO motd (message)
+        VALUES ($1)
+        `,
+        [trimmedMessage]
+      );
+
+      await redisClient.set('motd:current', trimmedMessage, {
+        EX: 60,
+      });
+
+      return res.status(201).json({
+        message: 'MOTD updated',
+        motd: trimmedMessage,
+      });
+    } catch (error) {
+      console.error(error);
+      return res.status(500).json({
+        error: 'Internal server error',
+      });
+    }
+  });
+}

src/index.ts

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+import dotenv from 'dotenv';
+import express from 'express';
+import { createClient } from 'redis';
+import { initDb } from './db.js';
+import { httpMotd } from './http/motd.js';
+
+dotenv.config();
+
+const app = express();
+app.use(express.json());
+
+const port = Number(3000);
+
+export const redisClient = createClient({
+  url: process.env.REDIS_URL,
+});
+
+redisClient.on('error', (err) => {
+  console.error('Redis error:', err);
+});
+
+async function main(): Promise<void> {
+  await redisClient.connect();
+  await initDb();
+
+  await httpMotd(app);
+
+  app.listen(port, () => {
+    console.log(`Listening on port ${port}`);
+  });
+}
+
+main().catch((error) => {
+  console.error('Failed to start app:', error);
+  process.exit(1);
+});