Project to control accounts, the functionalities that it has are transfer, get all transactions, get all received transactions, get all sent transactions and get account balance.

• Maven - Dependency Management
• JDK - Java™ Platform, Standard Edition Development Kit
• Spring Boot - Framework to easy the bootstrapping and development of new Spring Applications
• git - Free and Open-Source distributed version control system

• Postman - API Development Environment (Testing Docmentation)

There are several ways to run a Spring Boot application on your local machine. One way is to execute the main method in the com.trasnfermoney.TransferMoneyApplication class from your IDE.

• Download the zip or clone the Git repository.
• Unzip the zip file (if you downloaded one)
• Open Command Prompt and Change directory (cd) to folder containing pom.xml
• Open Eclipse
  • File -> Import -> Existing Maven Project -> Navigate to the folder where you unzipped the zip
  • Select the project
• Choose the Spring Boot Application file (search for @SpringBootApplication)
• Right Click on the file and Run as Java Application

Alternatively you can use the Spring Boot Maven plugin like so:

mvn spring-boot:run

The project has initialization information that is defined in the class com.trasnfermoney.config.DataLoader.java, the load information is:

• User id: 12345 - It has an account number 1000001 with $5000 and account number 1000003 with $500
• User id: 12346 - It has an account number 1000002 with $10000
• User id: 12347 - It has an account number 1000004 with $1000.50

After that the following transfers are made:

• From 1000001 to 1000003 with 1000
• From 1000002 to 1000004 with 1500
• From 1000004 to 1000003 with 10

And finally the final data are:

• User id: 12345 - have account number 1000001 with $4000 and account number 1000003 with $1510
• User id: 12346 - have account number 1000002 with $8500
• User id: 12347 - have account number 1000004 with $2490.50

The project (project directory) has a particular directory structure. A representative project is shown below:

.
├── Spring Elements
├── src
│   └── main
│       └── java
│           ├── com.trasnfermoney
│           ├── com.trasnfermoney.config
│           ├── com.trasnfermoney.controller
│           ├── com.trasnfermoney.exception
│           ├── com.trasnfermoney.model
│           ├── com.trasnfermoney.dto
│           ├── com.trasnfermoney.repository
│           └── com.trasnfermoney.service
├── src
│   └── main
│       └── resources
│           ├── application.properties
├── src
│   └── test
│       └── java
│           └── com.trasnfermoney
│               ├── TransferMoneyApplicationTests.java
├── JRE System Library
├── Maven Dependencies
├── src
├── target
├── mvnw
├── mvnw.cmd
├── pom.xml
└── README.md

• config — to configurate the API prefix and load the data with going to start the application ;

• model — to hold our entities;

• dto — to hold our data transfer objects;

• repositoriy — to communicate with memory data (Accounts and Users);

• service — to hold our business logic;

• exception — to hold our personalized exceptions;

• controller — to listen to the client;

• resources/application.properties - It contains application-wide properties. Spring reads the properties defined in this file to configure your application. You can define server’s default port, server’s context path, database URLs etc, in this file.

• test/ - contains unit and integration tests

• pom.xml - contains all the project dependencies

The REST API to the example app is described below.

POST /create/

curl --location --request POST 'http://localhost:8080/api/create' \
--header 'Content-Type: application/json' \
--data-raw '{
"account": 123456789,
"balance": 45450.00,
"owner": 7612333392
}'

HTTP/1.1 201 CREATED

[]

POST /transfer

curl --location --request POST 'http://localhost:8080/api/transfer' \
--header 'Content-Type: application/json' \
--data-raw '{
"fromAccount": 1000001,
"toAccount": 1000003,
"amount": 10.54
}'

HTTP/1.1 200 OK

[]

GET /{userId}/accounts/{accountNumber}/balance

curl --location --request GET 'http://localhost:8080/api/7612333392/accounts/123456789/balance'

HTTP/1.1 200 OK

{
    "balance": {
        "account": 123456789,
        "balance": 45450.0,
        "owner": 7612333392,
        "createdAt": "2020-02-24T05:28:17.040+0000"
    }
}

GET /{userId}/accounts/{accountNumber}/transactions/all

curl --location --request GET 'http://localhost:8080/api/12345/accounts/1000001/transactions/all'

HTTP/1.1 200 OK

{
    "transactions": [
        {
            "fromAccount": 1000001,
            "toAccount": 1000003,
            "amount": 1000.0,
            "sentAt": "2020-02-24T05:46:12.095+0000"
        }
    ]
 }

GET /{userId}/accounts/{accountId}/transactions/received

curl --location --request GET 'http://localhost:8080/api/12345/accounts/1000003/transactions/received'

HTTP/1.1 200 OK

{
	    "transactions": [
	        {
	            "fromAccount": 1000001,
	            "toAccount": 1000003,
	            "amount": 1000.0,
	            "sentAt": "2020-02-24T05:46:12.095+0000"
	        },
	        {
	            "fromAccount": 1000004,
	            "toAccount": 1000003,
	            "amount": 10.0,
	            "sentAt": "2020-02-24T05:46:12.095+0000"
	        }
	    ]
	}

GET /{userId}/accounts/{accountId}/transactions/sent

curl --location --request GET 'http://localhost:8080/api/12345/accounts/1000001/transactions/sent'

HTTP/1.1 200 OK

{
    "transactions": [
        {
            "fromAccount": 1000001,
            "toAccount": 1000003,
            "amount": 1000.0,
            "sentAt": "2020-02-24T05:46:12.095+0000"
        }
    ]
}