1. Overview
This course provides a detailed discussion on the backend development process using Spring Boot, the implementation of login and logout features using Spring Security, and the implementation of user registration functionality. You will also learn how to create entity classes for interacting with a database.
2. What is Spring Boot?
Spring Boot is a framework for developing Java-based web applications, built on top of the Spring Framework. Spring Boot minimizes configuration and provides various features to help developers focus solely on business logic. In particular, its powerful autoconfiguration feature allows easy implementation of business logic without complex configurations.
3. What is Spring Security?
Spring Security is a framework responsible for securing Spring-based applications. It provides authentication and authorization capabilities, making it easy to set up the security of the application. In this course, you will learn how to manage user authentication and permissions using Spring Security.
4. Project Setup
In this course, we will use IntelliJ IDEA as the IDE and Maven as the project management tool. Before getting started, follow the steps below to set up the project.
- Open IntelliJ IDEA and create a new project.
- Select Maven and set the Group ID and Artifact ID. (e.g., com.example, spring-security-demo)
- Add ‘Spring Web’, ‘Spring Security’, ‘Spring Data JPA’, and ‘H2 Database’ to the Dependencies.
- After creating the project, open the
src/main/resources/application.propertiesfile and add the database configuration.
5. Database Configuration
Configure the application.properties file as follows to use the H2 database.
spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=
spring.h2.console.enabled=true
spring.jpa.hibernate.ddl-auto=create
6. Create Entity
Now, we will create an entity class for interacting with the database. Let’s create a User entity class to store user information.
import javax.persistence.*;
@Entity
@Table(name = "users")
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
@Column(nullable = false, unique = true)
private String username;
@Column(nullable = false)
private String password;
@Column(nullable = false)
private String role;
// Getters and Setters
}
7. Implement User Registration Functionality
We will implement a REST API for user registration. When a registration request comes in, we will validate the request and add the user to the database.
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class UserService {
@Autowired
private UserRepository userRepository;
public void register(User user) {
// Password encryption logic (using BCryptPasswordEncoder)
user.setPassword(passwordEncoder.encode(user.getPassword()));
userRepository.save(user);
}
}
8. Implement Login and Logout
We will configure Spring Security to implement login and logout functionalities. Authentication will be performed based on the information provided by the user.
import org.springframework.context.annotation.Bean;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {
@Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
auth.inMemoryAuthentication()
.withUser("user")
.password("{noop}password")
.roles("USER");
}
@Override
protected void configure(HttpSecurity http) throws Exception {
http
.authorizeRequests()
.antMatchers("/register").permitAll()
.anyRequest().authenticated()
.and()
.formLogin()
.loginPage("/login")
.permitAll()
.and()
.logout()
.permitAll();
}
}
9. Implement REST API
We will now implement a REST API to allow users to register and log in to the web application.
import org.springframework.web.bind.annotation.*;
@RestController
@RequestMapping("/api")
public class UserController {
@Autowired
private UserService userService;
@PostMapping("/register")
public ResponseEntity register(@RequestBody User user) {
userService.register(user);
return ResponseEntity.ok("User registered successfully");
}
@GetMapping("/login")
public String login() {
return "Login Page";
}
}
10. Testing and Verification
To test the implemented functionalities, use a tool like Postman to call the APIs below.
- User Registration: Send a POST request to
/api/registerwith user information in JSON format. - Login: After user authentication, you can access the
/loginpage.
11. Conclusion
In this course, we explored in depth the basics of backend development using Spring Boot and Spring Security, up to the implementation of user registration and login functionalities. Through this course, we hope to enhance your understanding of backend development and help you build a foundation for practical application.
12. Next Steps
Now you have the ability to build a basic backend application. We recommend the next steps include exploring authentication using JWT (JSON Web Token), designing RESTful APIs, and implementing more diverse functionalities.