This is a RESTful API to hold transactions and provide realtime statistics for the last 60 seconds.
This endpoint is called to create a new transaction.
Request:
{
"amount": "12.3343",
"timestamp": "2018-07-17T09:59:51.312Z"
}
Where:
amount – transaction amount; a string of arbitrary length that is parsable as a BigDecimal timestamp – transaction time in the ISO 8601 format YYYY-MM-DDThh:mm:ss.sssZ in the UTC timezone (this is not the current timestamp)
Returns: Empty body with one of the following:
201 – in case of success
204 – if the transaction is older than 60 seconds
400 – if the JSON is invalid
422 – if any of the fields are not parsable or the transaction date is in the future
This endpoint returns the statistics based on the transactions that happened in the last 60 seconds. It executes in constant time and memory (O(1)).
Response:
{
"sum": "1000.00",
"avg": "100.53",
"max": "200000.49",
"min": "50.23",
"count": 10
}
Where:
sum – a BigDecimal specifying the total sum of transaction value in the last 60 seconds
avg – a BigDecimal specifying the average amount of transaction value in the last 60 seconds
max – a BigDecimal specifying single highest transaction value in the last 60 seconds
min – a BigDecimal specifying single lowest transaction value in the last 60 seconds
count – a long specifying the total number of transactions that happened in the last 60 seconds
All BigDecimal values always contain exactly two decimal places and use HALF_ROUND_UP
rounding. eg: 10.345 is returned as 10.35 10.8 is returned as 10.80
This endpoint causes all existing transactions to be deleted
The endpoint should accept an empty request body and return a 204 status code.
Clone this repository
git clone https://github.com/sojida/Transaction-Statistics.git
Install packages
npm install
Environment Variables
cp example.env .env
npm run start:dev
npm start
The application listens on port 4000 by default.