Accident Management System(AMS)

Project Description

Accident Management System(AMS) is the project implemented with Event-Driven Architectural approach
that provides messages distribution across several services based on their event type, ACCIDENT_TYPE.
It is simulation of what happens when some kind of accident happens,
it can be criminal, car, fire or some kind of accident that are saved in some
(in case of default settings: accident.events) source topic.
The list of services (repositories on github):

• accident-event-stream - app that produces large amound of data as event stream and distributes them across services.
• emergency-service - app that is responsible of handling corresponding data to response an accident in emergency way
• fire-rescue-service - app that is responsible of handling corresponding data to response an accident in emergency way
• law-enforcement-service - app that is responsible of handling corresponding data to response an accident in emergency way
• statistics-service - app that collects and analyzes data

Table of Contents

• Visual
• Installation
• Usage

Visual

Used Technologies

• Event-Driven Architecture
• Java 17+
• Spring Boot 3.1.x & Spring Boot JPA
• Apache Kafka & Kafka Streams library
• Docker
• Git
• Gitlab CI/CD

Project status

Ready for use

---

Installation

Prerequisites

• Java 17+ (JAVA_HOME must be set)
• Maven 3.8+ (MAVEN_HOME must be set)
• Docker
• Docker Compose

Application starting steps

1. Create working folder and clone the repositories:

   mkdir ams
   cd ams
   git clone https://gitlab.com/projectAMS/accident-event-stream.git
   git clone https://gitlab.com/projectAMS/emergency-service.git
   git clone https://gitlab.com/projectAMS/fire-rescue-service.git
   git clone https://gitlab.com/projectAMS/police-service.git
   git clone https://gitlab.com/projectAMS/statistics-service.git
   git clone https://gitlab.com/projectAMS/gitlab-profile.git scripts
   mvn clean package -f .\accident-event-stream -am
   mvn clean package -f .\emergency-service -am
   mvn clean package -f .\fire-rescue-service -am
   mvn clean package -f .\statistics-service -am
   mvn clean package -f .\statistics-service -am

2. Run kafka cluster + confluent schema registry with docker compose:

   docker-compose -f .\scripts\docker-compose.yml up -d

3. Start AMS event stream service:

    ./scripts/start-ams-event-stream.sh

   or if windows:````

    ./scripts/start-ams-event-stream.bat

   Note: every time you run the script new instance are created.```` For simplicity, it is limited to 3 instances, subsequent instances will be idle. Same for other services.
   properties with default values:

   BOOTSTRAP_SERVERS=localhost:9092,localhost:9093
   STATE_STORE_CACHE_MAX_SIZE=0
   STATE_DIRECTORY=./state-dir
   AVRO_SUBJECT_VERSION=latest
   SCHEMA_REGISTRY_URL=http://localhost:8081
   SOURCE_TOPIC_NAME=accident.events
   DLT_SOURCE_TOPIC_NAME=accident.events-dlt
   EMERGENCY_SERVICE_TOPIC_NAME=emergency.events
   POLICE_SERVICE_TOPIC_NAME=police.events
   FIRE_RESCUE_SERVICE_TOPIC_NAME=fire-rescue.events
   STATISTICS_SERVICE_TOPIC_NAME=statistics.events

   example of properties with custom values:

   ./scripts/start-emergency-service.sh --SERVER_PORT=8081 --BOOTSTRAP_SERVERS=localhost:9092,localhost:9093 \
      --STATE_STORE_CACHE_MAX_SIZE=1000 --STATE_DIRECTORY=./custom-directory \
      --SOURCE_TOPIC_NAME=accident.events --DLT_SOURCE_TOPIC_NAME.name=accident.events-dlt

   3.1 start emergency service:

   ./scripts/start-emergency-service.sh

   or if windows:

   ./scripts/start-emergency-service.bat

   properties with default values:

   BOOTSTRAP_SERVERS=localhost:9092,localhost:9093
   SCHEMA_REGISTRY_URL=http://localhost:8081
   POSTGRES_URL=jdbc:postgresql://localhost:5432/accident_management_service
   POSTGRES_USER=postgres
   POSTGRES_PASSWORD=test
   MAIN_TOPIC_NAME=emergency.events
   DLT_TOPIC_NAME=emergency.events-dlt

   example of properties with custom values:

   ./scripts/start-emergency-service.sh --SERVER_PORT=8081 --BOOTSTRAP_SERVERS=localhost:9092,localhost:9093 \
      --POSTGRES_URL=jdbc:postgresql://localhost:5432/accident_management_service --POSTGRES_PASSWORD=testpass \
      --MAIN_TOPIC_NAME=emergency.events --DLT_TOPIC_NAME.name=emergency.events-dlt

   3.2 start fire rescue service:

   ./scripts/start-fire-resque-service.sh

   properties with default values:

    ...
    KAFKA_MAIN_TOPIC_NAME=fire-rescue.events
    KAFKA_DLT_TOPIC_NAME=fire-rescue.events-dlt

   3.3 start police service:

   ./scripts/start-police-service.sh

   properties with default values:

    ...
    KAFKA_MAIN_TOPIC_NAME=police.events
    KAFKA_DLT_TOPIC_NAME=police.events-dlt

   3.4 start statistics service:

   ./scripts/start-statistics-service.sh

   properties with default values:

    ...
    KAFKA_MAIN_TOPIC_NAME=statistics.events
    KAFKA_DLT_TOPIC_NAME=statistics.events-dlt

Usage

1. Start the stream bombarder application: [NOT FINISHED]

    ./scripts/start-stream-bombarder.sh

   delay period between iterations in seconds is calculated by:

   int wait = (int) Math.floor(random.nextDouble(1.5) * 1000.0);

   and number of events sending per iteration:

   private static List<?> getEvents(double scale) {
        List<?> events = new ArrayList<>();
        int randomInt  = new Random().nextInt(100);
        int scaled = (int)((double) randomInt * scale);
        for(int i = 0; i < scaled; ++i) {
            events.add(getAccidentModel());
        }
        return events;
    }

   properties with default values:

    bootstrap.servers=localhost:9092,localhost:9093
    client.id=stream-bombarder
    enable.idempotence=true
    schema.registry.url=http://localhost:8081
    topic=accident.events
    scale=1

   example of properties with custom values:

    ./scripts/start-stream-bombarder.sh --bootstrap.servers=localhost:9092,localhost:9093 \
        --client.id=stream-bombarder --schema.registry.url=http://localhost:8081 --scale=10