IoT Developer Skill

I help you build IoT applications, connect sensors and devices, and create smart home/industrial IoT solutions.

What I Do

Device Integration:

Microcontroller programming (Arduino, ESP32) Sensor reading and data collection Actuator control (motors, LEDs, relays) Hardware interfacing

Communication:

MQTT messaging WebSocket connections REST API integration Bluetooth/WiFi connectivity

IoT Platforms:

Real-time dashboards Device management Data logging Alerts and automation MQTT Basics (Web Client) npm install mqtt

// lib/mqtt-client.ts import mqtt from 'mqtt'

export class MQTTClient { private client: mqtt.MqttClient

constructor(brokerUrl: string) { this.client = mqtt.connect(brokerUrl, { clientId: web_${Math.random().toString(16).slice(3)}, clean: true, connectTimeout: 4000 })

this.client.on('connect', () => {
  console.log('MQTT connected')
})

this.client.on('error', error => {
  console.error('MQTT error:', error)
})

}

subscribe(topic: string, callback: (message: string) => void) { this.client.subscribe(topic, err => { if (err) console.error('Subscribe error:', err) })

this.client.on('message', (receivedTopic, message) => {
  if (receivedTopic === topic) {
    callback(message.toString())
  }
})

}

publish(topic: string, message: string) { this.client.publish(topic, message) }

disconnect() { this.client.end() } }

Usage:

'use client' import { useEffect, useState } from 'react' import { MQTTClient } from '@/lib/mqtt-client'

export function TemperatureDashboard() { const [temperature, setTemperature] = useState(0) const [humidity, setHumidity] = useState(0)

useEffect(() => { const mqtt = new MQTTClient('ws://broker.hivemq.com:8000/mqtt')

mqtt.subscribe('home/temperature', (msg) => {
  setTemperature(parseFloat(msg))
})

mqtt.subscribe('home/humidity', (msg) => {
  setHumidity(parseFloat(msg))
})

return () => mqtt.disconnect()

}, [])

return (

Temperature

{temperature}°C

  <div className="p-6 bg-white rounded-lg shadow">
    <h3 className="text-gray-600">Humidity</h3>
    <p className="text-4xl font-bold">{humidity}%</p>
  </div>
</div>

) }

Arduino/ESP32 Code Temperature Sensor (DHT22) // ESP32 + DHT22 Temperature/Humidity Sensor

include

define DHTPIN 4

define DHTTYPE DHT22

const char ssid = "YOUR_WIFI_SSID"; const char password = "YOUR_WIFI_PASSWORD"; const char* mqtt_server = "broker.hivemq.com";

WiFiClient espClient; PubSubClient client(espClient); DHT dht(DHTPIN, DHTTYPE);

void setup() { Serial.begin(115200); dht.begin();

// Connect to WiFi WiFi.begin(ssid, password); while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println("WiFi connected");

// Connect to MQTT client.setServer(mqtt_server, 1883); }

void loop() { if (!client.connected()) { reconnect(); } client.loop();

// Read sensor float temperature = dht.readTemperature(); float humidity = dht.readHumidity();

// Publish to MQTT if (!isnan(temperature)) { client.publish("home/temperature", String(temperature).c_str()); }

if (!isnan(humidity)) { client.publish("home/humidity", String(humidity).c_str()); }

delay(5000); // Publish every 5 seconds }

void reconnect() { while (!client.connected()) { if (client.connect("ESP32Client")) { Serial.println("MQTT connected"); } else { delay(5000); } } }

Smart Home Dashboard 'use client' import { useEffect, useState } from 'react' import { MQTTClient } from '@/lib/mqtt-client'

interface Device { id: string name: string type: 'light' | 'sensor' | 'thermostat' status: string | number }

export function SmartHomeDashboard() { const [devices, setDevices] = useState([ { id: '1', name: 'Living Room Light', type: 'light', status: 'off' }, { id: '2', name: 'Temperature', type: 'sensor', status: 22 }, { id: '3', name: 'Thermostat', type: 'thermostat', status: 20 } ])

const [mqtt, setMqtt] = useState(null)

useEffect(() => { const client = new MQTTClient('ws://broker.hivemq.com:8000/mqtt')

// Subscribe to device topics
client.subscribe('home/light/1', (msg) => {
  updateDevice('1', msg)
})

client.subscribe('home/temperature', (msg) => {
  updateDevice('2', parseFloat(msg))
})

setMqtt(client)

return () => client.disconnect()

}, [])

const updateDevice = (id: string, status: string | number) => { setDevices(prev => prev.map(device => device.id === id ? { ...device, status } : device )) }

const toggleLight = (id: string) => { const device = devices.find(d => d.id === id) if (device && mqtt) { const newStatus = device.status === 'on' ? 'off' : 'on' mqtt.publish(home/light/${id}, newStatus) updateDevice(id, newStatus) } }

return (

Smart Home

  <div className="grid md:grid-cols-2 lg:grid-cols-3 gap-4">
    {devices.map((device) => (
      <div key={device.id} className="p-6 bg-white rounded-lg shadow">
        <h3 className="font-semibold mb-2">{device.name}</h3>

        {device.type === 'light' && (
          <button
            onClick={() => toggleLight(device.id)}
            className={`px-4 py-2 rounded ${
              device.status === 'on'
                ? 'bg-yellow-400 text-black'
                : 'bg-gray-300'
            }`}
          >
            {device.status === 'on' ? '💡 ON' : '🌑 OFF'}
          </button>
        )}

        {device.type === 'sensor' && (
          <p className="text-2xl font-bold">{device.status}°C</p>
        )}

        {device.type === 'thermostat' && (
          <div>
            <p className="text-xl">Target: {device.status}°C</p>
            <div className="flex gap-2 mt-2">
              <button className="px-3 py-1 bg-blue-600 text-white rounded">
                -
              </button>
              <button className="px-3 py-1 bg-blue-600 text-white rounded">
                +
              </button>
            </div>
          </div>
        )}
      </div>
    ))}
  </div>
</div>

) }

WebSocket Real-Time Sensor Data // app/api/sensor-stream/route.ts export async function GET(req: Request) { const encoder = new TextEncoder()

const stream = new ReadableStream({ start(controller) { const interval = setInterval(async () => { // Simulate sensor data (or read from actual IoT device) const temperature = 20 + Math.random() * 10 const humidity = 40 + Math.random() * 20

    const data = `data: ${JSON.stringify({
      temperature,
      humidity,
      timestamp: new Date().toISOString()
    })}\n\n`

    controller.enqueue(encoder.encode(data))
  }, 1000)

  req.signal.addEventListener('abort', () => {
    clearInterval(interval)
    controller.close()
  })
}

})

return new Response(stream, { headers: { 'Content-Type': 'text/event-stream', 'Cache-Control': 'no-cache', Connection: 'keep-alive' } }) }

When to Use Me

Perfect for:

Building smart home systems Creating industrial IoT solutions Implementing sensor networks Developing device dashboards Automating physical processes

I'll help you:

Connect IoT devices Implement MQTT protocols Read sensor data Build real-time dashboards Control actuators What I'll Create 🌡️ Sensor Integration 💡 Smart Device Control 📊 IoT Dashboards 📡 MQTT Communication 🏠 Smart Home Systems 🏭 Industrial IoT

Let's connect the physical and digital worlds!

iot-developer

安装

Temperature

include

include

include

define DHTPIN 4

define DHTTYPE DHT22

Smart Home