I have created the APIs for following operations.
- Creating and fetching accounts.
- Credit money into account.
- Transfer money between accounts.
One of the major requirement for this service was that it should be light weight thats why I have chosen the tech stack keeping in mind the memory footprint and througput of librariees used, I have avoided libraries that are known to eat RAM.
Second requirement was regarding the in memory datastore and thread safety.
- Spark
- JOOQ
- H2
- Flyway
- Google Guice
- I am using H2 (In memory) database, every time we start the application it gives us a prestine database.
- Account, Ledger and Transaction tables are being used to provide a consistent and verifiable data store.
- Long is the unit of money not Double, so 10.75$ is represented as 1075 cents.
- For simplicity, I am not taking care of currencies. I am assuming that all accounts deal in same currency.
- mvn -Pjooq-generate
- mvn clean package
- java -jar ./target/moneytransfer-jar-with-dependencies.jar
- mvn -Pjooq-generate
- mvn clean test
| Request | Response |
|---|---|
| curl -X PUT http://localhost:8080/accounts \ -H 'Accept: /' \ -H 'Content-Type: application/json' \ -H 'Host: localhost:8080' \ -d '{"name": "Prashant"}' |
{ "uuid" : "8757ff87-16f4-4a84-bb16-a1db7650e467", "name" : "Prashant", "balance" : 0 } |
| curl -X PUT http://localhost:8080/accounts \ -H 'Accept: /' \ -H 'Content-Type: application/json' \ -H 'Host: localhost:8080' \ -d '{"name": "Karan"}' |
{ "uuid" : "da751052-1cd5-441c-8c85-9e638dc9d3df", "name" : "Karan", "balance" : 0 } |
| curl -X POST http://localhost:8080/accounts/8757ff87-16f4-4a84-bb16-a1db7650e467/credit \ -H 'Accept: /' \ -H 'Content-Type: application/json' \ -H 'Host: localhost:8080' \ -d '{ "amount": 5000 }' |
{ "uuid" : "8757ff87-16f4-4a84-bb16-a1db7650e467", "name" : "Prashant", "balance" : 5000 } |
| curl -X POST http://localhost:8080/accounts/8757ff87-16f4-4a84-bb16-a1db7650e467/transfer \ -H 'Accept: /' \ -H 'Content-Type: application/json' \ -H 'Host: localhost:8080' \ -d '{"to": "da751052-1cd5-441c-8c85-9e638dc9d3df", "amount": 1000}' |
{ "uuid" : "8757ff87-16f4-4a84-bb16-a1db7650e467", "name" : "Prashant", "balance" : 4000 } |
| curl -X GET http://localhost:8080/accounts/da751052-1cd5-441c-8c85-9e638dc9d3df \ -H 'Accept: /' \ -H 'Host: localhost:8080' |
{ "uuid" : "da751052-1cd5-441c-8c85-9e638dc9d3df", "name" : "Karan", "balance" : 1000 } |
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