Panduan Lengkap Node-RED untuk IoT: Visual Programming Otomasi

// ========================================
// Flow 1: Monitoring Suhu + Otomasi Kipas
// ========================================
//
// [mqtt-in] ──▶ [function: proses_suhu] ──▶ [ui_gauge]
//                                        ──▶ [ui_chart]
//                                        ──▶ [function: otomasi_kipas]
//                                                  │
//                              ┌──────────────────┤
//                              ▼                  ▼
//                        [function: ON]    [function: OFF]
//                              │                  │
//                              ▼                  ▼
//                        [mqtt-out]          [mqtt-out]
//                     kipas: ON            kipas: OFF

// ========================================
// Node Function: proses_suhu
// ========================================
var data = msg.payload;
var suhu = parseFloat(data.suhu);
var kelembaban = parseFloat(data.kelembaban);
var timestamp = new Date().toLocaleTimeString('id-ID');

// Simpan ke global untuk diakses API
global.set('suhuTerkini', suhu);
global.set('kelembabanTerkini', kelembaban);
global.set('terakhirUpdate', timestamp);

// Kirim data untuk gauge
gauge_msg = { payload: suhu };
node.send([gauge_msg, null, null, null]);

// Kirim data untuk chart
chart_msg = {
  payload: [
    { series: ["Suhu", "Kelembaban"],
      data: [[suhu], [kelembaban]],
      labels: [timestamp] }
  ]
};
node.send([null, chart_msg, null, null]);

// Kirim suhu untuk logika otomasi
otomasi_msg = { payload: { suhu: suhu } };
node.send([null, null, otomasi_msg, null]);

// ========================================
// Node Function: otomasi_kipas
// ========================================
var suhu = msg.payload.suhu;
var thresholdHidup = 30;  // Suhu di atas 30°C: kipas ON
var thresholdMati = 27;   // Suhu di bawah 27°C: kipas OFF
var statusKipas = global.get('statusKipas') || 'off';

if (suhu >= thresholdHidup && statusKipas === 'off') {
  // Aktifkan kipas
  global.set('statusKipas', 'on');
  node.send([{
    payload: JSON.stringify({ status: "on",
      suhuAktif: suhu }),
    topic: "actuator/kipas/rumah"
  }, null]);
} else if (suhu <= thresholdMati && statusKipas === 'on') {
  // Matikan kipas
  global.set('statusKipas', 'off');
  node.send([null, {
    payload: JSON.stringify({ status: "off",
      suhuMatikan: suhu }),
    topic: "actuator/kipas/rumah"
  }]);
}

// ========================================
// Flow 2: Kontrol Lampu via Dashboard
// ========================================
//
// [ui_switch] ──▶ [function] ──▶ [mqtt-out]
//                                   Topic: actuator/lampu/rumah
//
// Node Function:
//   msg.topic = "actuator/lampu/rumah";
//   msg.payload = JSON.stringify({
//     status: msg.payload ? "on" : "off",
//     timestamp: new Date().toISOString()
//   });
//   return msg;
//
// ui_switch config:
//   Group: Kontrol Lampu
//   Label: "Lampu Ruang Tamu"
//   On Payload: true
//   Off Payload: false
//   On Icon: lightbulb (fa-lightbulb)
//   Off Icon: lightbulb-o (fa-lightbulb-o)
//
// ========================================
// Flow 2b: Kontrol via Timer/Schedule
// ========================================
//
// [ui_timepicker] ──▶ [function] ──▶ [change] ──▶ [mqtt-out]
//                                              Topic: actuator/lampu/schedule
//
// Timer bisa dikirim ke ESP32 untuk
// scheduling lokal di mikrokontroler.

// ========================================
// Flow 3: HTTP API untuk Status Rumah
// ========================================
//
// Endpoint 1: GET /api/status
// [http-in GET] ──▶ [function] ──▶ [http-response]
//
// Function:
//   msg.payload = {
//     suhu: global.get("suhuTerkini") || 0,
//     kelembaban: global.get("kelembabanTerkini") || 0,
//     lampu: global.get("statusLampu") || "off",
//     kipas: global.get("statusKipas") || "off",
//     lastUpdate: global.get("terakhirUpdate") || "-",
//     timestamp: new Date().toISOString()
//   };
//   msg.headers = { "Content-Type": "application/json" };
//   return msg;
//
// Endpoint 2: POST /api/alert
// [http-in POST] ──▶ [function: validate] ──▶ [mqtt-out]
//                                      └──▶ [http-response]
//
// Bisa dipanggil dari aplikasi mobile atau
// monitoring service seperti Grafana.

// ========================================
// Flow 4: Dashboard Lengkap
// ========================================
//
// Tab: "Monitoring Rumah"
// │
// ├── Group: "Sensor Suhu & Kelembaban"
// │   ├── [ui_gauge]     Suhu (°C)
// │   ├── [ui_gauge]     Kelembaban (%)
// │   ├── [ui_chart]     Histori Suhu
// │   └── [ui_text]      Status Terakhir
// │
// ├── Group: "Kontrol Perangkat"
// │   ├── [ui_switch]    Lampu Ruang Tamu
// │   ├── [ui_switch]    Lampu Kamar
// │   ├── [ui_slider]    Kecerahan Lampu (0-100)
// │   └── [ui_dropdown]  Mode Kipas (Auto/Manual/OFF)
// │
// └── Group: "Status Sistem"
//     ├── [ui_text]      Status MQTT Broker
//     ├── [ui_text]      Uptime Node-RED
//     └── [ui_text]      Jumlah Device Online