moneymate

MoneyMate - A Rest API for money transfers between internal users and accounts.

• Built in Java 8 / Dropwizard / JDBI / H2 (in memory).
• No Spring libraries were used / abused.
• Requires Maven

Usage

Clone this git repository

git clone https://github.com/genericmethod/moneymate.git

Navigate to the working directory

cd moneymate

Build the jar

mvn package

Execute the jar

java -jar target/moneymate-api-1.0.0-SNAPSHOT.jar server money-mate.yml

Execute the above in a using a single command

git clone https://github.com/genericmethod/moneymate.git && cd moneymate && mvn package && java -jar target/moneymate-api-1.0.0-SNAPSHOT.jar server money-mate.yml

Server starts on port 8080

Endpoints

- GET     /v1/users - get all users
- POST    /v1/users - create a user
- DELETE  /v1/users/{id} - delete a user by his id
- PUT     /v1/users/{id} - update a user
- GET     /v1/users/{username} - get a user by username
- GET     /v1/users/{username}/account - get a user account
- GET     /v1/accounts - get all accounts
- POST    /v1/accounts - add an account
- GET     /v1/accounts/{id} - get an account by id
- PUT     /v1/accounts/{id} - update an account
- GET     /v1/accounts/{id}/balance - get account balance
- DELETE  /v1/accounts/{username} - delete an account by username
- PUT     /v1/accounts/{username}/deposit - deposit money into an account
- PUT     /v1/accounts/{username}/withdraw - withdraw money from an account
- POST    /v1/transfers - transfer money between accounts

Http Status Code Summary

200 OK - Everything worked as expected
204 No Content - Everything worked as expected and not additional content was sent back
422 Unprocessable Entity - The request might have missing / incorrect parameters or failed certain conditions
404 Not Found - The requested resource does not exist

Account Resources

GET /v1/accounts

Example

Request

GET /v1/accounts

Response

[
  {
    "id": 1,
    "username": "chris",
    "description": "salary account",
    "balance": 888,
    "currency": "EUR"
  },
  {
    "id": 2,
    "username": "mark",
    "description": "salary account",
    "balance": 888,
    "currency": "EUR"
  }
]

POST /v1/accounts

Example

Request

POST /v1/accounts

Body

{
  "username":"vlad",
  "description":"description",
  "balance":123.00,
  "currency":"EUR"
}

Response

{
  "username":"vlad",
  "description":"description",
  "balance":123.00,
  "currency":"EUR"
}

GET /v1/accounts/{id}

Example

Request

GET /v1/accounts/1

Response

{
  "username":"vlad",
  "description":"description",
  "balance":123.00,
  "currency":"EUR"
}

PUT /v1/accounts/{id}

Example

Request

PUT /v1/accounts/{id}

Body

{
  "id":1,
  "username":"vlad",
  "description":"updated description",
  "balance":123.00,
  "currency":"EUR"
}

Response

{
  "id":1,
  "username":"vlad",
  "description":"updated description",
  "balance":123.00,
  "currency":"EUR"
}

GET /v1/accounts/{id}/balance

Example

Request

GET /v1/accounts/1/balance

Response

{
  "amount": 123,
  "currency": "EUR"
}

DELETE /v1/accounts/{username}

Example

Request

DELETE  /v1/accounts/vlad

Response

STATUS 204 OK

PUT /v1/accounts/{username}/withdraw

Example

Request

PUT /v1/accounts/vlad/withdraw

Body

{
  "amount": 10,
  "currency": "EUR"
}

Response

{
  "id": 1,
  "username": "vlad",
  "description": "description",
  "balance": 113,
  "currency": "EUR"
}

PUT /v1/accounts/{username}/deposit

Example

Request

PUT /v1/accounts/vlad/deposit

Body

{
  "amount": 10,
  "currency": "EUR"
}

Response

{
  "id": 2,
  "username": "mark",
  "description": "salary account",
  "balance": 1031.22,
  "currency": "EUR"
}

User Resources

GET /v1/users

Example

Request

GET /v1/users

Response

[
  {
    "id": 1,
    "username": "vlad",
    "email": "[email protected]"
  },
  {
    "id": 2,
    "username": "nik",
    "email": "[email protected]"
  }
]

POST /v1/users

Example

Request

POST /v1/users

Body

 {
    "username": "nik",
    "email": "[email protected]"
 }

Response

 {
     "id": 2,
     "username": "nik",
     "email": "[email protected]"
 }

DELETE /v1/users/{id}

Example

Request

DELETE /v1/users/4

Response

STATUS 204

PUT /v1/users/{id}

Example

Request

PUT /v1/users/2

Body

 {
    "id": 2,
    "username": "nik",
    "email": "[email protected]"
 }

Response

 {
    "id": 2,
    "username": "nik",
    "email": "[email protected]"
 }

GET /v1/users/{username}

Example

Request

GET /v1/users/vlad

Response

{
  "id": 1,
  "username": "vlad",
  "email": "[email protected]"
}

GET /v1/users/{username}/account

Example

Request

GET /v1/users/vlad/account

Response

{
  "id": 1,
  "username": "vlad",
  "description": "salary account",
  "balance": 888,
  "currency": "EUR"
}

Transferring Money

POST /v1/transfers

Example

Request

POST /v1/transfers

Body

{
  "amount":123.00,
  "currency":"EUR",
  "sourceAccountId":"1",
  "destinationAccountId":"2"
}

Response

STATUS 204

Next Steps

• Store transactions for each withdraw / deposit / transfer
• Enrich documentation
• Add further database constraints
• Implement versioning using headers as well apart from path
• Further inline documentation / info logs
• API Health checks
• Use a money library to handle monetary values - joda-money / java-money
• Use Wiremock and Rest-Assured for integration testing

In retrospect could have used a smaller framework such as SparkJava