Implement Bodenfeuchte app: MQTT listener, SQLite storage, chart UI, Docker

- Custom Next.js server starts MQTT listener on boot
- Subscribes to zigbee2mqtt/Bodenfeuchte_1, stores soil_moisture in SQLite
- API route /api/data returns last 6 hours of measurements
- Frontend shows current value + Recharts line chart, auto-refresh every 60s
- Dockerfile + docker-compose with persistent volume for SQLite DB

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -35,6 +35,12 @@ yarn-error.log*
 .env.local
 .env.*.local
 
+# sqlite data
+/data/*.db
+
+# compiled server
+/dist
+
 # vercel
 .vercel
 

Dockerfile

@@ -0,0 +1,27 @@
+FROM node:20-alpine AS deps
+WORKDIR /app
+COPY package*.json ./
+RUN npm ci --omit=dev
+
+FROM node:20-alpine AS builder
+WORKDIR /app
+COPY package*.json ./
+RUN npm ci
+COPY . .
+RUN npm run build
+RUN npx tsc --project tsconfig.server.json
+
+FROM node:20-alpine AS runner
+WORKDIR /app
+ENV NODE_ENV=production
+
+COPY --from=deps /app/node_modules ./node_modules
+COPY --from=builder /app/.next ./.next
+COPY --from=builder /app/dist ./dist
+COPY --from=builder /app/public ./public
+COPY package*.json ./
+
+RUN mkdir -p data
+
+EXPOSE 3000
+CMD ["node", "dist/server.js"]

app/api/data/route.ts

@@ -0,0 +1,8 @@
+import { getLast6Hours } from '@/lib/db';
+
+export const dynamic = 'force-dynamic';
+
+export async function GET() {
+  const rows = getLast6Hours();
+  return Response.json(rows);
+}

app/page.tsx

@@ -1,65 +1,106 @@
-import Image from "next/image";
+'use client';
+
+import { useEffect, useState } from 'react';
+import {
+  LineChart,
+  Line,
+  XAxis,
+  YAxis,
+  CartesianGrid,
+  Tooltip,
+  ResponsiveContainer,
+} from 'recharts';
+
+type Measurement = {
+  timestamp: number;
+  soil_moisture: number;
+};
+
+function formatTime(ts: number): string {
+  return new Date(ts).toLocaleTimeString('de-DE', {
+    hour: '2-digit',
+    minute: '2-digit',
+  });
+}
 
 export default function Home() {
+  const [data, setData] = useState<Measurement[]>([]);
+  const [lastUpdate, setLastUpdate] = useState<string>('');
+
+  const fetchData = async () => {
+    const res = await fetch('/api/data');
+    const json: Measurement[] = await res.json();
+    setData(json);
+    setLastUpdate(new Date().toLocaleTimeString('de-DE'));
+  };
+
+  useEffect(() => {
+    fetchData();
+    const interval = setInterval(fetchData, 60_000);
+    return () => clearInterval(interval);
+  }, []);
+
+  const latest = data.at(-1);
+
   return (
-    <div className="flex flex-col flex-1 items-center justify-center bg-zinc-50 font-sans dark:bg-black">
+    <main className="min-h-screen bg-gray-950 text-gray-100 p-8">
-      <main className="flex flex-1 w-full max-w-3xl flex-col items-center justify-between py-32 px-16 bg-white dark:bg-black sm:items-start">
+      <h1 className="text-2xl font-semibold mb-1">Bodenfeuchte</h1>
-        <Image
+      <p className="text-sm text-gray-400 mb-6">
-          className="dark:invert"
+        Letzte 6 Stunden · Aktualisierung: {lastUpdate || '…'}
-          src="/next.svg"
+      </p>
-          alt="Next.js logo"
+
-          width={100}
+      {latest && (
-          height={20}
+        <div className="mb-8 inline-block bg-gray-800 rounded-xl px-6 py-4">
-          priority
+          <span className="text-5xl font-bold text-green-400">
-        />
+            {latest.soil_moisture.toFixed(1)}
-        <div className="flex flex-col items-center gap-6 text-center sm:items-start sm:text-left">
+          </span>
-          <h1 className="max-w-xs text-3xl font-semibold leading-10 tracking-tight text-black dark:text-zinc-50">
+          <span className="text-2xl text-gray-400 ml-2">%</span>
-            To get started, edit the page.tsx file.
+          <p className="text-xs text-gray-500 mt-1">
-          </h1>
+            {formatTime(latest.timestamp)} Uhr
-          <p className="max-w-md text-lg leading-8 text-zinc-600 dark:text-zinc-400">
-            Looking for a starting point or more instructions? Head over to{" "}
-            <a
-              href="https://vercel.com/templates?framework=next.js&utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-              className="font-medium text-zinc-950 dark:text-zinc-50"
-            >
-              Templates
-            </a>{" "}
-            or the{" "}
-            <a
-              href="https://nextjs.org/learn?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
-              className="font-medium text-zinc-950 dark:text-zinc-50"
-            >
-              Learning
-            </a>{" "}
-            center.
           </p>
         </div>
-        <div className="flex flex-col gap-4 text-base font-medium sm:flex-row">
+      )}
-          <a
+
-            className="flex h-12 w-full items-center justify-center gap-2 rounded-full bg-foreground px-5 text-background transition-colors hover:bg-[#383838] dark:hover:bg-[#ccc] md:w-[158px]"
+      <div className="bg-gray-900 rounded-2xl p-4" style={{ height: 360 }}>
-            href="https://vercel.com/new?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
+        {data.length === 0 ? (
-            target="_blank"
+          <div className="flex items-center justify-center h-full text-gray-500">
-            rel="noopener noreferrer"
+            Noch keine Daten vorhanden
-          >
+          </div>
-            <Image
+        ) : (
-              className="dark:invert"
+          <ResponsiveContainer width="100%" height="100%">
-              src="/vercel.svg"
+            <LineChart data={data} margin={{ top: 8, right: 16, bottom: 8, left: 0 }}>
-              alt="Vercel logomark"
+              <CartesianGrid strokeDasharray="3 3" stroke="#374151" />
-              width={16}
+              <XAxis
-              height={16}
+                dataKey="timestamp"
-            />
+                tickFormatter={formatTime}
-            Deploy Now
+                stroke="#6b7280"
-          </a>
+                tick={{ fontSize: 12 }}
-          <a
+                minTickGap={40}
-            className="flex h-12 w-full items-center justify-center rounded-full border border-solid border-black/[.08] px-5 transition-colors hover:border-transparent hover:bg-black/[.04] dark:border-white/[.145] dark:hover:bg-[#1a1a1a] md:w-[158px]"
+              />
-            href="https://nextjs.org/docs?utm_source=create-next-app&utm_medium=appdir-template-tw&utm_campaign=create-next-app"
+              <YAxis
-            target="_blank"
+                domain={[0, 100]}
-            rel="noopener noreferrer"
+                unit="%"
-          >
+                stroke="#6b7280"
-            Documentation
+                tick={{ fontSize: 12 }}
-          </a>
+                width={45}
-        </div>
+              />
-      </main>
+              <Tooltip
-    </div>
+                formatter={(v) => [`${Number(v).toFixed(1)} %`, 'Bodenfeuchte']}
+                labelFormatter={(ts) => formatTime(Number(ts))}
+                contentStyle={{ background: '#1f2937', border: 'none', borderRadius: 8 }}
+              />
+              <Line
+                type="monotone"
+                dataKey="soil_moisture"
+                stroke="#4ade80"
+                strokeWidth={2}
+                dot={false}
+                activeDot={{ r: 4 }}
+              />
+            </LineChart>
+          </ResponsiveContainer>
+        )}
+      </div>
+    </main>
   );
 }

docker-compose.yml

@@ -0,0 +1,13 @@
+services:
+  bodenfeuchte:
+    build: .
+    ports:
+      - "3000:3000"
+    volumes:
+      - bodenfeuchte-data:/app/data
+    env_file:
+      - .env
+    restart: unless-stopped
+
+volumes:
+  bodenfeuchte-data:

lib/db.ts

@@ -0,0 +1,37 @@
+import Database from 'better-sqlite3';
+import path from 'path';
+
+const DB_PATH = path.join(process.cwd(), 'data', 'bodenfeuchte.db');
+
+let db: Database.Database;
+
+export function getDb(): Database.Database {
+  if (!db) {
+    db = new Database(DB_PATH);
+    db.exec(`
+      CREATE TABLE IF NOT EXISTS measurements (
+        id        INTEGER PRIMARY KEY AUTOINCREMENT,
+        timestamp INTEGER NOT NULL,
+        soil_moisture REAL NOT NULL
+      );
+      CREATE INDEX IF NOT EXISTS idx_timestamp ON measurements(timestamp);
+    `);
+  }
+  return db;
+}
+
+export function insertMeasurement(soilMoisture: number): void {
+  const stmt = getDb().prepare(
+    'INSERT INTO measurements (timestamp, soil_moisture) VALUES (?, ?)'
+  );
+  stmt.run(Date.now(), soilMoisture);
+}
+
+export function getLast6Hours(): { timestamp: number; soil_moisture: number }[] {
+  const since = Date.now() - 6 * 60 * 60 * 1000;
+  return getDb()
+    .prepare(
+      'SELECT timestamp, soil_moisture FROM measurements WHERE timestamp >= ? ORDER BY timestamp ASC'
+    )
+    .all(since) as { timestamp: number; soil_moisture: number }[];
+}

lib/mqtt-listener.ts

@@ -0,0 +1,35 @@
+import mqtt from 'mqtt';
+import { insertMeasurement } from './db';
+
+const TOPIC = 'zigbee2mqtt/Bodenfeuchte_1';
+
+export function startMqttListener(): void {
+  const client = mqtt.connect({
+    host: process.env.MQTT_BROKER ?? 'nuccy',
+    port: Number(process.env.MQTT_PORT ?? 1882),
+    username: process.env.MQTT_USER ?? 'rxf',
+    password: process.env.MQTT_PASSWORD ?? '',
+  });
+
+  client.on('connect', () => {
+    console.log('[MQTT] Connected, subscribing to', TOPIC);
+    client.subscribe(TOPIC);
+  });
+
+  client.on('message', (_topic, payload) => {
+    try {
+      const data = JSON.parse(payload.toString());
+      const value = data?.soil_moisture;
+      if (typeof value === 'number') {
+        insertMeasurement(value);
+        console.log('[MQTT] Stored soil_moisture:', value);
+      }
+    } catch {
+      console.error('[MQTT] Failed to parse message');
+    }
+  });
+
+  client.on('error', (err) => {
+    console.error('[MQTT] Error:', err.message);
+  });
+}

package.json

@@ -3,24 +3,30 @@
   "version": "0.1.0",
   "private": true,
   "scripts": {
-    "dev": "next dev",
+    "dev": "ts-node --project tsconfig.server.json server.ts",
     "build": "next build",
-    "start": "next start",
+    "start": "node dist/server.js",
+    "build:server": "tsc --project tsconfig.server.json",
     "lint": "eslint"
   },
   "dependencies": {
+    "better-sqlite3": "^12.10.0",
+    "mqtt": "^5.15.1",
     "next": "16.2.6",
     "react": "19.2.4",
-    "react-dom": "19.2.4"
+    "react-dom": "19.2.4",
+    "recharts": "^3.8.1"
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4",
+    "@types/better-sqlite3": "^7.6.13",
     "@types/node": "^20",
     "@types/react": "^19",
     "@types/react-dom": "^19",
     "eslint": "^9",
     "eslint-config-next": "16.2.6",
     "tailwindcss": "^4",
+    "ts-node": "^10.9.2",
     "typescript": "^5"
   }
 }

server.ts

@@ -0,0 +1,19 @@
+import { createServer } from 'http';
+import { parse } from 'url';
+import next from 'next';
+import { startMqttListener } from './lib/mqtt-listener';
+
+const dev = process.env.NODE_ENV !== 'production';
+const app = next({ dev });
+const handle = app.getRequestHandler();
+
+app.prepare().then(() => {
+  startMqttListener();
+
+  createServer((req, res) => {
+    const parsedUrl = parse(req.url ?? '/', true);
+    handle(req, res, parsedUrl);
+  }).listen(3000, () => {
+    console.log('> Ready on http://localhost:3000');
+  });
+});

tsconfig.server.json

@@ -0,0 +1,17 @@
+{
+  "compilerOptions": {
+    "target": "ES2020",
+    "module": "commonjs",
+    "moduleResolution": "node",
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "strict": true,
+    "outDir": "dist",
+    "rootDir": ".",
+    "paths": {
+      "@/*": ["./*"]
+    }
+  },
+  "include": ["server.ts", "lib/**/*.ts"],
+  "exclude": ["node_modules", ".next"]
+}