Remote IOT Sensor monitoring via MQTT and InfluxDB

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  "name": "Remote IOT Sensor monitoring via MQTT and InfluxDB",
  "tags": [],
  "nodes": [
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      "parameters": {
        "width": 340,
        "height": 120,
        "content": "MQTT trigger subscribed to a topic called wokwi-weather via a Mosquitto MQTT broker. The trigger receives the temperature and humidity payloads from a DHT22 sensor connected to a remote ESP32 microcontroller "
      },
      "typeVersion": 1
    },
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      "type": "n8n-nodes-base.stickyNote",
      "position": [
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      "parameters": {
        "height": 100,
        "content": "Javascript code to extract the temperature and humidity values to ensure correct JSON format for the database"
      },
      "typeVersion": 1
    },
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      "position": [
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      "parameters": {
        "width": 260,
        "height": 120,
        "content": "HTTP request node posts temperature and humidity data from the DHT22 sensor to the InfluxDB data bucket running on a local host http://localhost:8086"
      },
      "typeVersion": 1
    },
    {
      "id": "020858a6-7771-4322-8eb6-b83e99b3563d",
      "name": "Remote Sensor MQTT Trigger",
      "type": "n8n-nodes-base.mqttTrigger",
      "position": [
        -580,
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      ],
      "parameters": {
        "topics": "wokwi-weather",
        "options": {}
      },
      "credentials": {
        "mqtt": {
          "id": "xtd75tjk1hKlQOba",
          "name": "MQTT account"
        }
      },
      "typeVersion": 1
    },
    {
      "id": "51e6f59f-9b93-4121-8db4-7f47b929fdf5",
      "name": "Data ingest to InfluxDB bucket",
      "type": "n8n-nodes-base.httpRequest",
      "position": [
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      "parameters": {
        "url": "http://localhost:8086/api/v2/write?orgID=<Organization ID>&bucket=<InfluxDB bucket name>&precision=s",
        "body": "={{ $json.payload }}",
        "method": "POST",
        "options": {},
        "sendBody": true,
        "contentType": "raw",
        "sendHeaders": true,
        "headerParameters": {
          "parameters": [
            {
              "name": "Authorization",
              "value": "Token  <API Token value generated in InfluxDB>"
            }
          ]
        }
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      "typeVersion": 4.2
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      "name": "Payload data preparation node",
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      "parameters": {
        "jsCode": "// Try to parse the incoming message as JSON
let data;
try {
  data = JSON.parse($json.message); // $json.message is expected to be a JSON string
} catch (e) {
  // If parsing fails, throw an error
  throw new Error(\"Invalid JSON in MQTT message\");
}

// Get the topic from the input, or use a default value
const topic = $json.topic || \"unknown-topic\";

// Make sure humidity and temp are numbers
if (typeof data.humidity !== \"number\" || typeof data.temp !== \"number\") {
  throw new Error(\"Missing or invalid humidity/temp in MQTT message\");
}

// Create a formatted string like: \"topic_name humidity=45,temp=22\"
const line = `${topic} humidity=${data.humidity},temp=${data.temp}`;

// Return the result in the expected format
return [
  {
    json: {
      payload: line
    }
  }
];"
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      "typeVersion": 2
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  "pinData": {},
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  "connections": {
    "Remote Sensor MQTT Trigger": {
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    "Payload data preparation node": {
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