floortjetjeertes/krachbankapi

How floortjetjeertes/krachbankapi works

KrachBank API is a Spring Boot banking backend. Clients authenticate or register, then call REST endpoints for users, accounts, and transactions. Controllers validate and translate requests, services apply banking operations, and JPA repositories persist users, accounts, and transfers in the documented H2 store. JWT security protects authenticated requests. The sampled files confirm controller ownership and several integrations; service-to-repository links reflect the corresponding implementation modules, while transaction business rules were not sampled.

Components 24

REST API

Authentication Controller src/main/java/com/krachbank/api/controllers/AuthenticationController.java
Account Controller src/main/java/com/krachbank/api/controllers/AccountController.java
Transaction Controller src/main/java/com/krachbank/api/controllers/TransactionController.java
User Controller src/main/java/com/krachbank/api/controllers/UserController.java
Request DTOs src/main/java/com/krachbank/api/dto/DTO.java

Domain Services

Authentication Service src/main/java/com/krachbank/api/service/AuthenticationServiceJpa.java
User Service src/main/java/com/krachbank/api/service/UserServiceJpa.java
Account Service src/main/java/com/krachbank/api/service/AccountServiceJpa.java
Transaction Service src/main/java/com/krachbank/api/service/TransactionJpa.java

Persistence Layer

User Repository src/main/java/com/krachbank/api/repository/UserRepository.java
Authentication Repository src/main/java/com/krachbank/api/repository/AuthenticationRepository.java
Account Repository src/main/java/com/krachbank/api/repository/AccountRepository.java
Transaction Repository src/main/java/com/krachbank/api/repository/TransactionRepository.java
H2 Database
Database Seeder src/main/java/com/krachbank/api/seeders/DatabaseSeeder.java

Security

JWT Service src/main/java/com/krachbank/api/service/JwtService.java
JWT Filter src/main/java/com/krachbank/api/security/JwtAuthenticationFilter.java
Web Security src/main/java/com/krachbank/api/configuration/WebSecurityConfiguration.java
User Details Loader src/main/java/com/krachbank/api/service/UserDetailsServiceImpl.java

Banking Domain

Account Model src/main/java/com/krachbank/api/models/Account.java
Transaction Model src/main/java/com/krachbank/api/models/Transaction.java
User Model src/main/java/com/krachbank/api/models/User.java
IBAN Generator src/main/java/com/krachbank/api/configuration/IBANGenerator.java

Other components

API Client

Connections 32

API Client → Authentication Controller: sends credentials
API Client → Account Controller: manages accounts
API Client → Transaction Controller: submits transfers
API Client → User Controller: manages users
Authentication Controller → Request DTOs: reads requests
Account Controller → Request DTOs: returns DTOs
Transaction Controller → Request DTOs: maps DTOs
User Controller → Request DTOs: returns DTOs
Authentication Controller → User Service: registers users
Authentication Controller → Authentication Service: authenticates users
Account Controller → IBAN Generator: generates IBANs
Account Controller → Account Service: manages accounts
Transaction Controller → Account Service: resolves accounts
Transaction Controller → Transaction Service: creates transfers
User Controller → User Service: manages users
User Controller → Account Service: loads accounts
Authentication Service → Authentication Repository: finds credentials
Authentication Service → JWT Service: creates tokens
User Service → User Repository: stores users
Account Service → Account Repository: stores accounts
Transaction Service → Transaction Repository: stores transfers
JWT Filter → JWT Service: validates tokens
JWT Filter → User Details Loader: loads principals
Web Security → JWT Filter: dispatches filter
User Details Loader → User Repository: loads users
User Repository → H2 Database: persists users
Authentication Repository → H2 Database: persists users
Account Repository → H2 Database: persists accounts
Transaction Repository → H2 Database: persists transfers
Database Seeder → User Repository: seeds users
Database Seeder → Account Repository: seeds accounts
Database Seeder → Transaction Repository: seeds transfers

Drawn by GitDiagram on September 22, 2026 from the repository's file tree, README and source files. Read as Markdown