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Central Monitoring Service

The central-monitoring-service is a Spring Boot application that consumes Kafka messages to monitor temperature and humidity data. It prints alerts when the configurable thresholds for humidity and temperature are exceeded.

Table of Contents

• Requirements
• Project Structure
• Configuration
• Setup
• Running the Service
• Alerting Logic
• Customization

Requirements

Before running the service, ensure you have the following installed:

• Java 11+
• Maven
• Docker (for Kafka and Zookeeper) or a Kafka setup

Project Structure

.
├── src
│   ├── main
│   │   ├── java
│   │   │   └── com.central
│   │   │       ├── config
│   │   │       │   └── KafkaConsumerConfig.java
│   │   │       ├── listener
│   │   │       │   └── SensorEventListener.java
│   │   │       └── CentralMonitoringServiceApplication.java
│   │   └── resources
│   │       └── application.yml
└── pom.xml

• KafkaConsumerConfig.java: Configures the Kafka consumer properties.
• MonitoringService.java: Contains the business logic for monitoring humidity and temperature data based on configurable thresholds.
• application.yml: Configures Kafka topics, consumer settings, and sensor thresholds.

Configuration

The application.yml file allows you to configure Kafka properties, topics, and sensor thresholds. Here is an example configuration:

spring:
  application:
    name: central-monitoring-service
  sensor:
    threshold:
      humidity: 50
      temperature: 35
  kafka:
    consumer:
      bootstrap-servers: 127.0.0.1:9092
      groupid: central-service
      key-serializer: org.apache.kafka.common.serialization.StringSerializer
      value-serializer: org.apache.kafka.common.serialization.StringSerializer
      topic: sensor-topic

Setup

1. Clone the repository:

git clone https://github.com/vinkvii/central-monitoring-service.git
cd central-monitoring-service

2. Build the project using Maven:

mvn clean install

3. Run Kafka and Zookeeper:

You can use Docker Compose to quickly spin up Kafka and Zookeeper:

docker-compose up

Alternatively, you can run Kafka locally by following the Kafka Quickstart Guide.

4. Configure Kafka:

Ensure the application.yml file has the correct Kafka bootstrap server address.

Running the Service

You can run the service using the following command:

mvn spring-boot:run

The service will begin consuming messages from the Kafka topic (e.g., sensor-topic).

Alerting Logic

The service monitors the Kafka topic for sensor data and prints alerts based on the configured threshold values.

• Humidity: If the received humidity value crosses the configured threshold in application.yml, a message will be printed.
• Temperature: If the received temperature value crosses the configured threshold in application.yml, a message will be printed.

Example output:

ALERT: Humidity sensor h1 exceeded threshold with value 55
ALERT: Temperature sensor t1 exceeded threshold with value 32

Customization

You can customize the following:

• Thresholds: Modify the threshold values in the application.yml file:

  sensor:
    threshold:
      humidity: 50
      temperature: 35

• Kafka Topics: Change the topic to which the service listens in the application.yml file.

spring:
  kafka:
    consumer:
      bootstrap-servers: 127.0.0.1:9092
      groupid: central-service
      key-serializer: org.apache.kafka.common.serialization.StringSerializer
      value-serializer: org.apache.kafka.common.serialization.StringSerializer
      topic: sensor-topic

Feel free to adjust the service further to meet your specific monitoring needs.