🌱 Azure Farming IoT - Infrastructure Deployment

IoT infrastructure in Azure with Terraform, seamlessly integrating with existing backend resources.

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🚀 Overview

This Terraform script automates the deployment of an IoT-based smart farming system on Azure. The setup includes:

• IoT Hub → Serves as the MQTT broker for ESP32-based devices.
• Cosmos DB (MongoDB API) → Stores IoT sensor data.
• Azure Function App → Processes messages from IoT Hub and stores them in Cosmos DB.
• Storage Account → Used for function logs and metadata storage.

Note: Device Provisioning Service (DPS) can be included in future, to automate device registrations.

📌 Prerequisites

Before running Terraform, ensure that you have:

• Terraform installed (>=1.3)
• Azure CLI authenticated (az login)
• An active Azure Subscription (e.g., "Azure for Students")

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🛠 Deployment Steps

1️⃣ Initialize Terraform

terraform init

2️⃣ Preview Deployment Changes

terraform plan

3️⃣ Deploy Resources

terraform apply -auto-approve

4️⃣ Verify Deployment

Check deployed resources in Azure:

terraform state list

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📡 Setting Up IoT Devices in Azure IoT Hub

1️⃣ Create an IoT Device

az iot hub device-identity create --hub-name azurefarming-iothub --device-id ESP32-Device

2️⃣ Get Device Connection String

az iot hub device-identity show-connection-string --hub-name azurefarming-iothub --device-id ESP32-Device

3️⃣ Test MQTT Message Publishing

Simulate an ESP32 device sending telemetry:

curl -X POST https://azurefarming-function.azurewebsites.net/api/iot_event_handler -H "Content-Type: application/json" -d '{"temperature": 25, "humidity": 50}'

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🔗 Exposing IoT Data to the Web

1️⃣ Fetch IoT Device Status via API

Once the Azure Function is deployed, the backend API can fetch IoT device status:

curl -X GET "https://azurefarming-function.azurewebsites.net/api/device/{device_id}/status"

2️⃣ Sending Commands to IoT Devices

The web application can send control commands (e.g., turning on water pumps):

curl -X POST "https://azurefarming-function.azurewebsites.net/api/device/{device_id}/command" \
     -H "Content-Type: application/json" \
     -d '{"command": "water_on"}'

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🛑 Destroying Resources

To remove all deployed Azure resources:

terraform destroy -auto-approve

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📌 Why This Architecture?

✅ Modular Deployment → IoT Hub, Cosmos DB, and Functions are separately deployed for flexibility.

✅ Scalable → The system is designed to handle multiple devices and large data volumes.

✅ Web-Ready → The function API exposes IoT data to web and mobile applications.

✅ Secure Communication → IoT Hub ensures authenticated MQTT messaging for devices.

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🚀 Next Steps

1️⃣ Run the Terraform script ✅

2️⃣ Test MQTT communication with IoT Hub

3️⃣ Verify that IoT data is being stored in Cosmos DB

4️⃣ Expose the Function API for frontend integration