Banking API using Spring Boot, Spring Security, and JWT

A simple yet secure banking REST API built with Spring Boot, featuring JWT authentication, role-based access control, and transaction management. This project demonstrates backend development principles like layered architecture, secure authentication, database integration, clear documentation.

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Tech Stack

• Java 21
• Spring Boot 3
• Spring Security (JWT)
• Spring Data JPA (Hibernate)
• PostgreSQL
• Maven
• Lombok
• Validation & Exception Handler
• JUnit & Mockito
• Springdoc-OpenAPI (Swagger)

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⚙️ How to Run

# 1. Clone the repository
git clone https://github.com/zaidnshr1/BankingApp.git
cd BankingApp

# 2. Configure database & JWT Key in application.properties
spring.datasource.url=jdbc:postgresql://localhost:5432/yourdb (also create a database in your postgres)
spring.datasource.username=youruser
spring.datasource.password=yourpass
spring.jpa.hibernate.ddl-auto=update
spring.jpa.show-sql=true
application.security.jwt.secret-key=404E635266556A586E3272357538782F413F4428472B4B6250645367566B5970
application.security.jwt.expiration=86400000

# 3. Build the project
mvn clean install

# 4. Run the application
mvn spring-boot:run

# 5. Go to the PostgreSql
insert into roles (id, name) values (1, ROLE_CLIENT), (2, ROLE_ADMIN);

Server runs at:
http://localhost:8080

Main Endpoints

🔓 Public

POST /api/v1/auth/register-admin Register Admin account
POST /api/v1/auth/login Authenticate and receive JWT token

🔒 Private (Requires JWT)

Admin (Jwt From Login Admin)

POST /api/v1/admin/register-user Admin Register Client account
PUT /api/v1/admin/disable-account Admin Disable Client Account

Client (Jwt From Login Client)

POST //api/v1/account/deposit Client can deposit money
POST /api/v1/account/transfer Transfer to another accounts
GET /api/v1/account/history/{accountNumber} View transaction history
GET /api/v1/account/{accountNumber} View Account details
PUT /api/v1/account/edit-profile Update first or last name

📷 DOCUMENTATION

Creating Admin Account

the constraints:

• firstName : Not Null
• lastName : Not Null
• username : 8 characters
• preferredAccountNumber : 8 characters
• initialPin : 6 characters

1st, you can try to create an Admin account. it's public for easily setup purposes. As Admin, you can creating and disable the Client Account.

Admin Login

the constraints:

• username : Not Null
• initialPin : Not Null

2nd, if you want to create client account and then having transaction, you need the client account. To have client account, you need to create it as Admin. So, please login as Admin first :

• Go to POST /api/v1/auth/login
• Put the right username and pinNumber you already create before.
• Server will validating and generating the token if you pass the right username & password.
• Copy the token and scroll up to Authorize, click the button and paste the token for authorize.

Admin Creating Client Account

the constraints:

• adminAccountNumber : Not Null
• firstName : Not Null
• lastName: Not Null
• username : 8 Characters
• initialPin : 6 Characters
• preferredAccountNumber : 8 Characters

3rd, Creating the 1st client account. After that, you can have the initial balance which 0.

Client Login

the constraints:

• username : Not Null
• initialPin : Not Null

4th, Right now you are not will be admin anymore. You need being a client to have a transaction. So :

• Go to POST /api/v1/auth/login again
• Gain the token
• Remove the Admin token you login before, chane it by paste the client token

Deposit Money

the constraints:

• accountNumber : Not Null
• amount : Not Null

5th, You want to have a transaction right? you need money to transaction. So, you can deoposit goto POST //api/v1/account/deposit

About Account/Profile

6th, after deposit if you want to see your wallet is topped up or not just hit GET `/api/v1/account/{accountNumber} and you will see the money already added or not.

Transfer To Another Account

the constraints:

• sourceAccountNumber : 8 Characters
• targetAccountNumber : 8 Characters
• amount: Not Null
• description : nullable

7th, Now, you can transaction to another account if you know the target accountNumber.

• Go to POST /api/v1/account/transfer
• Make sure, if you want to transfer a person dont leave less than 15000 in your bank. It will rollback.
• If success, the your transaction has recorded into transaction history

View Transaction History

the constraints:

• accountNumber : 8 Characters
• page : (auto 0 or 1st page)
• size: (auto 10 per page)

8th, After having transaction you can see the proof or history in GET /api/v1/account/{accountNumber}

Change First / Last Name

8th, User can change the first or last name.