Advanced Api Template

Certainly! Below is a structured and clean code snippet for a Spring Boot application that includes the specified functionalities for a banking API. Please note that this is a simplified example, and you may need to adapt it to your specific requirements and integrate it with your database layer for persistence. ```java import org.springframework.beans.factory.annotation.Autowired; import org.springframework.http.HttpStatus; import org.springframework.http.ResponseEntity; import org.springframework.security.core.Authentication; import org.springframework.security.core.context.SecurityContextHolder; import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder; import org.springframework.web.bind.annotation.*; import javax.validation.Valid; @RestController @RequestMapping("/api/banking") public class BankingController { @Autowired private UserService userService; @Autowired private JwtTokenProvider jwtTokenProvider; @Autowired private AuthenticationManager authenticationManager; @Autowired private BCryptPasswordEncoder passwordEncoder; @PostMapping("/register") public ResponseEntity<?> registerUser(@Valid @RequestBody UserRegistrationRequest registrationRequest) { // Validate registration request, check for duplicate usernames or emails // Create a new user entity User user = new User(); user.setUsername(registrationRequest.getUsername()); user.setEmail(registrationRequest.getEmail()); user.setPassword(passwordEncoder.encode(registrationRequest.getPassword())); // Save the user to the database userService.saveUser(user); // Generate and return JWT token for successful registration String token = jwtTokenProvider.createToken(user.getUsername()); return ResponseEntity.ok(new JwtAuthenticationResponse(token)); } @PostMapping("/login") public ResponseEntity<?> loginUser(@Valid @RequestBody UserLoginRequest loginRequest) { // Authenticate the user Authentication authentication = authenticationManager.authenticate( new UsernamePasswordAuthenticationToken( loginRequest.getUsername(), loginRequest.getPassword() ) ); // Set authentication in SecurityContext SecurityContextHolder.getContext().setAuthentication(authentication); // Generate and return JWT token for successful login String token = jwtTokenProvider.createToken(loginRequest.getUsername()); return ResponseEntity.ok(new JwtAuthenticationResponse(token)); } @PostMapping("/setup-mfa") public ResponseEntity<?> setupMFA(@RequestBody MFASetupRequest mfaSetupRequest) { // Validate MFA setup request and save MFA details for the user return ResponseEntity.ok("Multi-Factor Authentication set up successfully"); } @PostMapping("/transfer-funds") public ResponseEntity<?> transferFunds(@RequestBody FundTransferRequest fundTransferRequest) { // Validate fund transfer request and process fund transfer return ResponseEntity.ok("Funds transferred successfully"); } // Exception handling for invalid requests or authentication failures @ExceptionHandler({InvalidRequestException.class, AuthenticationException.class}) public ResponseEntity<?> handleInvalidRequest(Exception ex) { return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(new ErrorResponse(ex.getMessage())); } // Exception handling for authorization failures @ExceptionHandler(AccessDeniedException.class) public ResponseEntity<?> handleAccessDeniedException(Exception ex) { return ResponseEntity.status(HttpStatus.FORBIDDEN).body(new ErrorResponse(ex.getMessage())); } // Other utility methods, if needed } ``` In this code snippet: - `UserRegistrationRequest`, `UserLoginRequest`, `MFASetupRequest`, and `FundTransferRequest` are assumed to be request DTOs (Data Transfer Objects) representing the incoming JSON payloads. - `JwtTokenProvider` is a service for JWT token generation. - `UserService` is a service that handles user-related operations like saving a new user. - `AuthenticationManager` is used to authenticate the user during login. - `BCryptPasswordEncoder` is used for password encoding. - Exception handling is demonstrated for various scenarios. Ensure to add proper dependencies in your `pom.xml` or `build.gradle` file for Spring Boot, Spring Security, JWT, validation, and any other dependencies required for your specific use case. Also, integrate the code with your data access layer for user persistence.