Restful API for transaction statistics. The main use case for our API is to calculate realtime statistic from the last 60 seconds. There will be three APIs, one of them is called every time a transaction is made. It is also the sole input of this rest API. The second one returns the statistic based of the transactions of the last 60 seconds.Third one is to delete all transactions.

mvn spring-boot:run

mvn test

POST /transactions : Every Time a new transaction happened, this endpoint will be called.

GET /statistics : Returns the statistic based on the transactions which happened in the last 60 seconds.

DELETE /transactions : Delete all transactions

According to the current time, the container provides all valid TransactionStatisticsAggregator(s) Statistics are calculated by iterating on all valid aggregators.

Every Time a new transaction happened, this endpoint will be called. Body: { "amount": 12.3, "timestamp": 1478192204000 }

Where: amount - transaction amount timestamp - transaction time in epoch in millis in UTC time zone (this is not current timestamp) Returns: Empty body with either 201 or 204. 201 - in case of success 204 - if transaction is older than 60 seconds Where: amount is a double specifying the amount time is a long specifying unix time format in milliseconds

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

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

Where: 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