Planned lessonJNR-036-L03

Users from the database

Lesson 3 of 8
Junior

On This Lesson 4 topics

In this lesson
Planned topics
Draft outline details
Practice

This lesson is planned. The outline below lists the topics it will cover. The full lesson has not been published yet.

In this lesson

authenticate against users stored in the Shop database.

Planned topics

UserDetailsService has one method: loadUserByUsername. It returns a UserDetails (name, password hash, authorities).
Load the user with a repository; throw UsernameNotFoundException if missing.
Spring Security compares the submitted password with the stored hash using a PasswordEncoder.
Map your role column to authorities; hasRole("ADMIN") looks for ROLE_ADMIN.
Never store plain passwords (next module covers hashing).

Draft outline details

Demonstration

java

@Service
class DbUserDetailsService implements UserDetailsService {
    public UserDetails loadUserByUsername(String email) {
        var u = users.findByEmail(email).orElseThrow(() -> new UsernameNotFoundException("no user"));
        return User.withUsername(u.getEmail()).password(u.getPasswordHash())
                   .roles(u.getRole()).build();
    }
}

Check your understanding

What does hasRole("ADMIN") look for?

Show answer

The authority ROLE_ADMIN.

Practice

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