How to update multiple mongo collections inside the same function in spring webflux?

Question

There are 2 collections in my mongoDB:

1. collection which contains user phone number and wwhether it is verified or not? 集合？

{
   _id: '12123',
   phones: [ 
      {
         phoneNumber: '1234567890',
         verified: false
      }
   ]
}

2. collection which contains the verification code mapped by id from user collection as . 集合，其中包含由用户集合中的id映射为的验证码。

{
   _id: '1111',
   userId: '12123',
   token: '4545'
}

I'm creating an endpoint in Spring WebFlux to verify the phone number. The endpoint receives the and . 和 。 If the token in the collection matches the token sent by the user, then update the verified to true in user collection.

I'm trying to write a single function that would be called by this endpoint and make the required changes.

I tried in the following code but the verified status is not updating to true.

   public Mono<VerifyPhoneToken> verifyPhoneNumber(String id, String verificationCode) {
        return verifyPhoneTokensRepository.findByUserId(id)
                .flatMap(vpt -> {
                    if (verificationCode.equals(vpt.getToken())) {
                        usersRepository.findById(id)
                                .flatMap(user -> {
                                    user.getPhones().get(0).setVerified(true);
                                    return usersRepository.save(user);
                                });
                        return verifyPhoneTokensRepository.save(vpt);
                    }
                    return null;
                });
    }

Also, I would like to know if return null can be handled in a better way.

Answer 1

im guessing your problem is when you are calling the usersRepository you are not handling the return thus breaking the event chain. You should try something like:

public Mono<VerifyPhoneToken> verifyPhoneNumber(String id, String verificationCode) {
    return verifyPhoneTokensRepository.findByUserId(id)
            .flatMap(vpt -> {
                if (verificationCode.equals(vpt.getToken())) {
                    return updateUser(id)
                            .then(verifyPhoneTokensRepository.save(vpt));
                }
                return Mono.empty();
            });
}

private Mono<User> updateUser(String id) {
    return usersRepository.findById(id)
            .flatMap(user -> {
                user.getPhones().get(0).setVerified(true);
                return usersRepository.save(user);
            });
}

using then to chain on your action. Also dont return null return Mono<Void> (Mono.empty())