Services Deep Dive

User Service (UserServiceImpl)

The UserServiceImpl is the orchestrator for all user lifecycle events.

1. User Registration (register)

This is a multi-step orchestration:

1. Duplicate Check: Verifies if the email or primary contact already exists in MongoDB.
2. Mapping: Uses UserMapper to convert RegisterDto to a User entity.
3. User ID Generation: Creates a unique userId using a SHA-256 hash.
4. Save User: Persists the initial User document to MongoDB.
5. Keycloak Sync: Calls the Auth Service to create the identity record.
6. Progress Tracking: Saves the initial RegistrationProgress record.
7. Security Setup: Initializes an empty SecurityDetails record.
8. Kafka Event: Publishes the first user-create-event.

2. Profile Management (updateUser)

Handles both status changes and profile updates:

• Locking: If isLockUser is true, sets status to BLOCKED and emits a Kafka event.
• Contacts: Manages primary and secondary contact numbers without deleting history.
• Addresses: Manages permanent and residential addresses, replacing existing ones of the same type.

Security Details Service (SecurityDetailsServiceImpl)

Manages sensitive security metadata and account integrity.

1. Update Security Credentials

Merges new security questions and answers into the SecurityDetails document. It then triggers the UserValidator to check if the registration is complete.

2. Login Failure Handling

Increments the loginFailedAttempts counter.

if (loginFailed) {
    securityDetails.setLoginFailedAttempts(securityDetails.getLoginFailedAttempts() + 1);
    if (securityDetails.getLoginFailedAttempts() >= 5) {
        // Trigger account block
        userService.updateUser(userId, new UserUpdateDto(true, null, null));
    }
}

Registration Engine (UserValidator)

The UserValidator is not a service but a utility consumed by the service layer. It acts as a state transition listener:

• Step 1 Complere?: Advance to ADD_ADDRESS.
• Step 2 Complete?: Advance to ADD_SECURITY_CREDENTIALS.
• Step 3 Complete?: Set status to REGISTRATION_COMPLETE.