Statistics calculation

API

Start the service

    mvn spring-boot:run

Execute tests

    mvn clean -U verify

Install

    mvn clean -U install

Endpoints

Add transaction

Every Time a new transaction happened, this endpoint will be called.

Request

POST /transactions

{
    "amount": 12.3,
    "timestamp": 1478192204000
}

Field	Description
amount	Transaction amount
timestamp	Transaction time in epoch in millis in UTC time zone (this is not current timestamp)

Response

Http Status	Description
201	Transaction successfully added
204	Transaction is older than 60 seconds

Get statistics

Get the statistic based on the transactions which happened in the last 60 seconds.

Request

GET /statistics

Response

{
    "sum": 1000,
    "avg": 100,
    "max": 200,
    "min": 50,
    "count": 10
}

Field	Description
sum	Is a double specifying the total sum of transaction value in the last 60 seconds
avg	Is a double specifying the average amount of transaction value in the last 60 seconds
max	Is a double specifying single highest transaction value in the last 60 seconds
min	Is a double specifying single lowest transaction value in the last 60 seconds
count	Is a long specifying the total number of transactions happened in the last 60 seconds

Configuration

# Configure port to use

server:
  port: 9000

# Precision in millisecods to calculate statitics.
# Min value 1
# Max value 1000

statistics.precision-milliseconds: 10

Docker support

Create Image

mvn clean package docker:build

Execute image

docker-compose up