Setting Up

This is a Spring Boot Application requires Java & Maven setup on the system. The Application uses MYSQL as database.

Steps to follow

• Setup MySQL. From the app directory run SQL script

mysql -u <username> -p <database_name> < scripts/oye.sql

• Edit src/main/resources/application.properties with your MySQL credentials.

spring.datasource.username=<username>
spring.datasource.password=<your-password>

• If IntelliJ is available, import this project as Maven project, it will automatically detect run configuration. Run Application.
• Or run from CLI using mvn spring-boot:run

After running, app will be available at http://localhost:8080

On clicking Connect button, you will start recieving real time location of drivers on web page at http://localhost:8080

To Find drivers in radius of 'r' say 200m use API - *GET 'http://localhost:8080/driver/find/range?radius=100&latitude=0.00&longitude=0.00'

Web Page Snippet Post Websocket connection

Overall Architecture

The web controller consists of two parts

• REST API
• Websocket: To push locations of all drivers every 1s.

Database stores one table called drivers, which stores following attributes

• driverId
• name
• latitude (till 7 decimals) - current lat of driver
• longitude (till 7 decimals) - current longitude of driver

REST APIs enable creating/updating/reading drivers. For find drivers within radius 'r' application uses MySql's ST_Distance_Sphere which is offered as Spatial Convenience Function from MySql 5.7

Websocket provides a channel called /topic/updates to which as WS client can subscribe. App has a scheduler which pushes location of drivers to the channel every 1s.

Code Structure

• controller - Code REST APIs exposed, defining request, response of APIs. ScheduledTasks.java is a scheduler to push all driver locations every 1s.
• service - Conatains business logic. TrackerService.java has business logic & db interactions.
• repository - Interface that actually interacts with DB calls via JPA.
• entity - Java classes that map to database objects.
• dto - API Request & Response Java objects
• config - Websocket & objectmapper config.

Testing

Didn't get time for Unit testing. Did fuctional testing with API calls. For real time updates made a small HTML page available at http://localhost:8080 which on clicking connect starts displaying realtime cordinates of drivers. Time Spent - Around 45 mins

REST APIs

Postman Collection - https://www.getpostman.com/collections/fe46b26aba3eb83ddab8

Following are the APIs

• POST /driver/add - To add new driver

Request
Status 201

curl --location --request POST 'http://localhost:8080/driver/add' \
--header 'Content-Type: application/json' \
--data-raw '{
    "name": "Hawkeye",
    "latitude": -0.00101,
    "longitude": -0.00101
}'

{
    "driverId": "689baf3c-f022-4711-b053-7b47328ae0f7",
    "name": "Hawkeye",
    "latitude": -0.00101,
    "longitude": -0.00101
}

• GET /driver/{driverId} - To get driver details

Request

curl --location --request GET 'http://localhost:8080/driver/689baf3c-f022-4711-b053-7b47328ae0f7'

Status 200
{
    "driverId": "689baf3c-f022-4711-b053-7b47328ae0f7",
    "name": "Hawkeye",
    "latitude": -0.0010100,
    "longitude": -0.0010100
}

• GET /driver/find/range - Find drivers in range

Request

curl --location --request GET 'http://localhost:8080/driver/find/range?radius=100&latitude=0.00&longitude=0.00'

Response
Status 200
{
    "drivers": [
        {
            "driverId": "9c7836c3-25eb-4174-a2d3-768fa72b7e5a",
            "name": "Spidey",
            "latitude": 0.0001000,
            "longitude": 0.0001000
        },
        {
            "driverId": "bbc7acb9-6e5c-47d6-86b4-abb3394f1b91",
            "name": "Thor",
            "latitude": 0.0001200,
            "longitude": 0.0001100
        }
    ]
}

• POST /driver/add - Update Driver (Should be a PUT request ideally)

curl --location --request POST 'http://localhost:8080/driver/add' \
--header 'Content-Type: application/json' \
--data-raw '{
    "driverId": "6025e2ee-e529-42d5-a64e-e1d15b22547d",
    "name": "Hulk",
    "latitude": -0.00301,
    "longitude": -0.00001
}'

Status 201
{
    "driverId": "6025e2ee-e529-42d5-a64e-e1d15b22547d",
    "name": "Hulk",
    "latitude": -0.00301,
    "longitude": -0.00001
}

• GET /driver/all - Update Driver

Request
curl --location --request GET 'http://localhost:8080/driver/all'

Response
[
    {
        "driverId": "6025e2ee-e529-42d5-a64e-e1d15b22547d",
        "name": "Hulk",
        "latitude": -0.0030100,
        "longitude": -0.0000100
    },
    {
        "driverId": "689baf3c-f022-4711-b053-7b47328ae0f7",
        "name": "Hawkeye",
        "latitude": -0.0010100,
        "longitude": -0.0010100
    },
    {
        "driverId": "9c7836c3-25eb-4174-a2d3-768fa72b7e5a",
        "name": "Spidey",
        "latitude": 0.0001000,
        "longitude": 0.0001000
    },
    {
        "driverId": "b7552562-020c-42b9-a475-1e0f1164f37d",
        "name": "Iron Man",
        "latitude": 0.0101000,
        "longitude": 0.0020000
    },
    {
        "driverId": "bbc7acb9-6e5c-47d6-86b4-abb3394f1b91",
        "name": "Thor",
        "latitude": 0.0001200,
        "longitude": 0.0001100
    }
]