Inserting data into related table with thymeleaf - spring

Question

I have table user and table wallet, table wallet have userId so they are connected.
I created controller like this:
#PostMapping("/user/{user_id}/wallets")
public ResponseEntity<?> createWallet(#PathVariable(value = "user_id") Long user_id,
#RequestBody Wallet walletRequest) {
if (walletRepository.existsByUserIdAndWalletName(user_id, walletRequest.getWalletName())) {
return ResponseEntity.badRequest().body(new MessageResponse("You already have wallet with that name, choose another!"));
}
Wallet comment = userRepository.findById(user_id).map(tutorial -> {
walletRequest.setUser(tutorial);
return walletRepository.save(walletRequest);
}).orElseThrow(() -> new IllegalArgumentException("Not found user with id = " + user_id));
return new ResponseEntity<>(comment, HttpStatus.CREATED);
}
And that works fine when I go in postman and hit API /api/user/1/wallets with the appropriate JSON body, I mean wallet is added to user with ID 1.
But I dont know how to transform this to consume in Thymeleaf?
This is all stuff that is related to this thing:
First of all API to show new wallet form:
#GetMapping("/showNewWalletForm")
public String showNewWalletForm(Model model) {
Wallet wallet = new Wallet();
model.addAttribute("wallet", wallet);
return "new_wallet";
}
Form inside html:
<form action="#" th:action="#{/api/wallet/saveWallet}" th:object="${wallet}" method="POST">
<input type="text" th:field="*{walletName}" placeholder="Wallet name" class="form-control mb-4 col-4">
<input type="text" th:field="*{initialBalance}" placeholder="Enter balance" class="form-control mb-4 col-4">
<button type="submit" class="btn btn-info col-2"> Save Wallet</button>
</form>
And API to save wallet:
#PostMapping("/saveWallet")
public String saveWallet(#ModelAttribute("wallet") Wallet wallet) {
// save employee to database
walletService.saveWallet(wallet);
return "redirect:/";
}
Obviously I'm getting Column 'user_id' cannot be null since I didnt set it anywhere as I did in postman.
This is Wallet class:
#Entity
#Table(name = "wallet")
public class Wallet {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#NotEmpty(message = "Please, insert a wallet name")
private String walletName;
private double initialBalance;
#ManyToOne(fetch = FetchType.LAZY, optional = false)
#JoinColumn(name = "user_id", nullable = false)
#OnDelete(action = OnDeleteAction.CASCADE)
#JsonIgnore
private User user;

Answer 1

To make this work, you need to be able to fetch the logged-in user and since this is something you will need often, I suggest that you create a Spring managed class.
#Component("CurrentUserUtility")
public class CurrentUserUtility {
public static UserDetailsImpl getCurrentUser() {
Authentication tAuthentication = getAuthentication();
if (tAuthentication != null) {
return (UserDetailsImpl) getAuthentication().getPrincipal();
} else {
return null;
}
}
private static Authentication getAuthentication() {
return SecurityContextHolder.getContext().getAuthentication();
}
}
UserDetailsImpl is the class implementing the UserDetails interface and this class should have a userId field (or any other field such as username or email that can be used to uniquely identify the current user).
Now, the only thing you need to do in you controller before saving a new wallet is retrieve the current user using the above utility class.
#PostMapping("/saveWallet")
public String saveWallet(#ModelAttribute("wallet") Wallet wallet) {
//user_id shoudn't be null after the next line
wallet.setUser(userRepository.findById( CurrentUserUtility.getCurrentUser().getUserId() ));
walletService.saveWallet(wallet);
return "redirect:/";
}