Spring Boot Backend Development Course, Implementing Login and Logout with Spring Security, User Registration, Adding Dependencies

This course covers the basics of backend development using Spring Boot and explains how to implement login, logout, and user registration functionalities through Spring Security.

1. What is Spring Boot?

Spring Boot is an application framework based on the Spring Framework that helps developers set up and run Spring applications more easily. It minimizes the complex setup process and provides an embedded server, allowing developers to quickly build applications. Its main features include:

  • Auto Configuration: Developers can run their applications using default values without having to write configuration files.
  • Dependency Management: Required libraries can be easily added through Maven or Gradle.
  • Control over Dependencies: You can pin specific versions of libraries.

2. Creating a Project

There are various ways to create a new project using Spring Boot, but the easiest way to get started is to use Spring Initializr. Let’s follow the steps below to create a project.

  1. Access Spring Initializr
  2. Select Project: Maven Project
  3. Select Language: Java
  4. Select Spring Boot: Latest Version
  5. Input Group: com.example
  6. Input Artifact: demo
  7. Select Dependencies: Spring Web, Spring Security, Spring Data JPA, H2 Database
  8. Click Generate to download the ZIP file

3. Understanding Project Structure

When you open the generated project, you can see the following main directory and file structure.

    ├── src
    │   ├── main
    │   │   ├── java
    │   │   │   └── com
    │   │   │       └── example
    │   │   │           └── demo
    │   │   │               ├── DemoApplication.java
    │   │   │               └── configuration
    │   │   │                   └── SecurityConfig.java
    │   │   └── resources
    │   │       ├── application.properties
    │   │       └── static
    │   └── test
    ├── pom.xml
    

Here, the DemoApplication.java file is the main application file, and application.properties is the configuration file.

4. Adding Dependencies

The project we created includes the necessary libraries as Maven dependencies. Let’s open the pom.xml file to check the added dependencies.

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>
        </dependency>
    </dependencies>
    

5. Implementing Registration Functionality

To allow users to register, we need to save and manage user information. For this purpose, we will create a user entity using JPA and set up the connection to the database.

5.1 Creating the User Entity

First, let’s create an entity class called User. This class holds user information.

    package com.example.demo.model;

    import javax.persistence.*;

    @Entity
    public class User {
        @Id
        @GeneratedValue(strategy = GenerationType.IDENTITY)
        private Long id;
        
        private String username;
        private String password;
        private String email;

        // Getters and Setters
    }
    

5.2 Creating UserRepository

Now, we will create a UserRepository interface to save and retrieve user information from the database.

    package com.example.demo.repository;

    import com.example.demo.model.User;
    import org.springframework.data.jpa.repository.JpaRepository;

    public interface UserRepository extends JpaRepository {
        User findByUsername(String username);
    }
    

5.3 Writing the Registration Service

We will write a service class to handle the registration logic.

    package com.example.demo.service;

    import com.example.demo.model.User;
    import com.example.demo.repository.UserRepository;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;

    @Service
    public class UserService {
        @Autowired
        private UserRepository userRepository;

        public User registerNewUser(User user) {
            return userRepository.save(user);
        }
    }
    

6. Configuring Spring Security

Now we will set up Spring Security to implement login and logout functionalities.

6.1 Creating SecurityConfig Class

We will create a class for security configuration.

    package com.example.demo.configuration;

    import com.example.demo.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    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;

    @Configuration
    @EnableWebSecurity
    public class SecurityConfig extends WebSecurityConfigurerAdapter {
        @Autowired
        private UserService userService;

        @Override
        protected void configure(AuthenticationManagerBuilder auth) throws Exception {
            auth.userDetailsService(userService);
        }

        @Override
        protected void configure(HttpSecurity http) throws Exception {
            http
                .authorizeRequests()
                    .antMatchers("/register", "/h2-console/**").permitAll()
                    .anyRequest().authenticated()
                .and()
                .formLogin()
                    .loginPage("/login")
                    .permitAll()
                .and()
                .logout()
                    .permitAll();
        }
    }
    

7. Implementing Registration and Login Controllers

We will write a controller to handle registration and login functionalities.

7.1 Creating AuthController Class

    package com.example.demo.controller;

    import com.example.demo.model.User;
    import com.example.demo.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.PostMapping;

    @Controller
    public class AuthController {
        @Autowired
        private UserService userService;

        @GetMapping("/register")
        public String showRegistrationForm(Model model) {
            model.addAttribute("user", new User());
            return "register";
        }

        @PostMapping("/register")
        public String registerUser(User user) {
            userService.registerNewUser(user);
            return "redirect:/login";
        }

        @GetMapping("/login")
        public String login() {
            return "login";
        }
    }
    

8. Creating Login/Logout Pages

Now we will create the login and registration pages. Create login.html and register.html files under the src/main/resources/templates folder.

8.1 register.html

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>User Registration</title>
    </head>
    <body>
        <h1>User Registration</h1>
        <form action="/register" method="post">
            <label>Username: </label><input type="text" name="username"><br>
            <label>Password: </label><input type="password" name="password"><br>
            <label>Email: </label><input type="email" name="email"><br>
            <input type="submit" value="Register">
        </form>
    </body>
    </html>
    

8.2 login.html

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Login</title>
    </head>
    <body>
        <h1>Login</h1>
        <form action="/login" method="post">
            <label>Username: </label><input type="text" name="username"><br>
            <label>Password: </label><input type="password" name="password"><br>
            <input type="submit" value="Login">
        </form>
    </body>
    </html>
    

9. Running the Application

Now that all configurations are complete, enter the following command in the terminal to run the application.

    mvn spring-boot:run
    

Open your browser and navigate to http://localhost:8080/register to proceed with the registration. You can then access the application by logging in.

10. Conclusion and Next Steps

In this course, we learned how to build a backend application using Spring Boot and implement basic login and registration functionalities with Spring Security. Now you can build upon this basic structure to add various features such as API token-based authentication and OAuth2 integration.

Suggested Next Steps

  • Implement API REST
  • Add JWT (JSON Web Token) based authentication
  • Enhance authentication with OAuth2
  • Create a complete application with frontend integration

Make great use of what you learned in this course to create fantastic projects!

Author: [Your Name]

Published Date: [Publish Date]

Spring Boot Backend Development Course, Implementing Login and Logout with Spring Security, Membership Registration, Writing Controllers

This course guides you through the process of developing backend applications using Spring Boot and implementing login, logout, and signup features through Spring Security. You will understand the basic structure of Spring Boot and the concepts of Spring Security, and you will write actual code to implement these features.

Chapter 1: What is Spring Boot?

Spring Boot is a lightweight application development tool based on the Spring framework. Using Spring Boot, you can easily build production-level Spring applications. In this chapter, we will explore the features and advantages of Spring Boot and how to install it.

1.1 Features of Spring Boot

  • Auto Configuration: Spring Boot automatically configures settings according to the application’s requirements.
  • Standalone: Spring Boot applications can be run without separate server installations.
  • Dependency Management: You can easily manage library dependencies using Maven or Gradle.
  • Presets: It provides various Spring Boot starters for starting new applications.

Chapter 2: Setting Up a Spring Boot Project

We will use Spring Initializr to set up the project. This tool allows you to easily add dependencies and initial configurations.

2.1 Using Spring Initializr

  1. Access the Spring Initializr website.
  2. Enter the project metadata (Group, Artifact, Name, etc.).
  3. Select the required dependencies (Spring Web, Spring Security, etc.).
  4. Unzip the downloaded ZIP file and open it in your IDE.

Chapter 3: Understanding the Basics of Spring Security

Spring Security is a framework that provides powerful and comprehensive authentication and authorization capabilities. In this chapter, we will understand the basic concepts of Spring Security and learn how to implement login and logout.

3.1 Authentication and Authorization

Authentication is the process of verifying a user’s identity, while Authorization is the process of verifying a user’s permissions to perform specific actions.

Chapter 4: Implementing Signup Features

Now you are ready to implement a simple signup feature. We will set up the necessary model, controller, and service layers.

4.1 Creating the User Model

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;

@Entity
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;
    private String username;
    private String password;

    // Getters and Setters
}

4.2 Implementing the Signup API

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping("/api/auth")
public class AuthController {

    @Autowired
    private UserService userService;

    @PostMapping("/register")
    public ResponseEntity register(@RequestBody User user) {
        return userService.register(user);
    }
}

Chapter 5: Implementing Login and Logout Features

With the signup feature implemented, we will now set up the login and logout features. We will implement the authentication process using Spring Security.

5.1 Configuring Spring Security

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
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;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;

@Configuration
@EnableWebSecurity
public class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
        auth.inMemoryAuthentication()
            .withUser("user").password(passwordEncoder().encode("password")).roles("USER");
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.csrf().disable()
            .authorizeRequests()
            .antMatchers("/api/auth/register").permitAll()
            .anyRequest().authenticated()
            .and()
            .httpBasic();
    }

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();
    }
}

5.2 Implementing the Login API

The login API can be handled using the basic functionalities of Spring Security. You can create a custom login page or utilize the default authentication of Spring Security.

Chapter 6: Writing Controllers

Finally, we will write a RESTful API controller to manage communication with the client. We will define and implement requirements for each endpoint.

6.1 Implementing the User API

import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping("/api/users")
public class UserController {

    @GetMapping("/{id}")
    public ResponseEntity getUser(@PathVariable Long id) {
        // logic to get user by id
    }

    @PutMapping("/{id}")
    public ResponseEntity updateUser(@PathVariable Long id, @RequestBody User user) {
        // logic to update user
    }
}

Conclusion

Through this course, you have learned the basics of backend development using Spring Boot and the concepts of authentication and authorization through Spring Security. I hope you continue to develop and expand upon the additional features you need.

Spring Boot Backend Development Course, Implement Login and Logout with Spring Security, User Registration, Create Entities

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.

  1. Open IntelliJ IDEA and create a new project.
  2. Select Maven and set the Group ID and Artifact ID. (e.g., com.example, spring-security-demo)
  3. Add ‘Spring Web’, ‘Spring Security’, ‘Spring Data JPA’, and ‘H2 Database’ to the Dependencies.
  4. After creating the project, open the src/main/resources/application.properties file 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.

  1. User Registration: Send a POST request to /api/register with user information in JSON format.
  2. Login: After user authentication, you can access the /login page.

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.

References and Recommended Resources

Spring Boot Backend Development Course, Implementing Login and Logout with Spring Security, User Registration, Running Tests

Hello! In this course, we will learn how to develop a backend application using Spring Boot and implement user authentication functionality through Spring Security. This course is suitable for beginners to intermediate learners, and each step will be explained in detail.

1. What is Spring Boot?

Spring Boot is a Java-based framework that simplifies the complex configurations of the existing Spring framework, making it easier to develop applications. It features auto-configuration and allows for quick project starts through various starter dependencies.

1.1 Features of Spring Boot

  • Auto-configuration: Automatically configures settings as needed, reducing the need for developers to manually set them up.
  • Starter dependencies: Provides pre-configured dependencies to easily use multiple libraries.
  • Production-ready: Facilitates deployment and operation through an embedded server, monitoring tools, etc.

2. Setting Up a Project

To set up a Spring Boot project, you can use an IDE like IntelliJ IDEA or set it up directly using Spring Initializr. Here, we will create a project using Spring Initializr.

2.1 Using Spring Initializr

  1. Visit Spring Initializr.
  2. Configure as follows:
    • Project: Gradle Project
    • Language: Java
    • Spring Boot: 2.5.4 (select an appropriate version)
    • Group: com.example
    • Artifact: demo
    • Dependencies: Spring Web, Spring Data JPA, Spring Security, H2 Database, Lombok
  3. Click the Generate button to download the project.

3. Introduction to Key Libraries and Technologies

Now that the project is created, let’s briefly introduce each library and technology.

3.1 Spring Web

Spring Web is a module for developing web applications. It supports RESTful web services and the MVC pattern.

3.2 Spring Data JPA

Spring Data JPA is a module designed to simplify interactions with databases, based on JPA (Java Persistence API). It allows for processing databases in an object-oriented manner using ORM (Object Relational Mapping).

3.3 Spring Security

Spring Security is a powerful security framework that supports authentication and authorization in applications. It provides access control for specific URLs, user authentication, and session management features.

3.4 H2 Database

H2 Database is a lightweight in-memory database written in Java. It can be very useful in development and testing stages.

4. Implementing User Registration Feature

The user registration feature is one of the basic functionalities of the application, responsible for storing user information in the database.

4.1 Creating Entity Class

Create a User entity class to store user information.

        
        package com.example.demo.model;

        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 email;

            // Getters and Setters
        }
        
        

4.2 Creating Repository Interface

Create a UserRepository interface that can interact with the database.

        
        package com.example.demo.repository;

        import com.example.demo.model.User;
        import org.springframework.data.jpa.repository.JpaRepository;

        public interface UserRepository extends JpaRepository {
            User findByUsername(String username);
        }
        
        

4.3 Creating Registration Service

Create a UserService class to handle the registration logic.

        
        package com.example.demo.service;

        import com.example.demo.model.User;
        import com.example.demo.repository.UserRepository;
        import org.springframework.beans.factory.annotation.Autowired;
        import org.springframework.security.crypto.password.PasswordEncoder;
        import org.springframework.stereotype.Service;

        @Service
        public class UserService {
            @Autowired
            private UserRepository userRepository;

            @Autowired
            private PasswordEncoder passwordEncoder;

            public void registerUser(User user) {
                user.setPassword(passwordEncoder.encode(user.getPassword()));
                userRepository.save(user);
            }
        }
        
        

4.4 Creating Registration Controller

Create a UserController to handle HTTP requests.

        
        package com.example.demo.controller;

        import com.example.demo.model.User;
        import com.example.demo.service.UserService;
        import org.springframework.beans.factory.annotation.Autowired;
        import org.springframework.web.bind.annotation.*;

        @RestController
        @RequestMapping("/api/users")
        public class UserController {
            @Autowired
            private UserService userService;

            @PostMapping("/register")
            public String register(@RequestBody User user) {
                userService.registerUser(user);
                return "Registration successful";
            }
        }
        
        

5. Configuring Spring Security

Now we will configure Spring Security to implement login and logout features.

5.1 Implementing WebSecurityConfigurerAdapter

Create a class for Spring Security configuration. Inherit from WebSecurityConfigurerAdapter to implement security settings.

        
        package com.example.demo.config;

        import com.example.demo.service.CustomUserDetailsService;
        import org.springframework.beans.factory.annotation.Autowired;
        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;
        import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
        import org.springframework.security.crypto.password.PasswordEncoder;

        @EnableWebSecurity
        public class SecurityConfig extends WebSecurityConfigurerAdapter {
            @Autowired
            private CustomUserDetailsService userDetailsService;

            @Override
            protected void configure(AuthenticationManagerBuilder auth) throws Exception {
                auth.userDetailsService(userDetailsService).passwordEncoder(passwordEncoder());
            }

            @Override
            protected void configure(HttpSecurity http) throws Exception {
                http.csrf().disable()
                    .authorizeRequests()
                    .antMatchers("/api/users/register").permitAll()
                    .anyRequest().authenticated()
                    .and()
                    .formLogin()
                    .loginPage("/login")
                    .permitAll()
                    .and()
                    .logout()
                    .permitAll();
            }

            @Bean
            public PasswordEncoder passwordEncoder() {
                return new BCryptPasswordEncoder();
            }
        }
        
        

5.2 Creating Class for User Details

Create a CustomUserDetailsService class to handle user authentication information in Spring Security.

        
        package com.example.demo.service;

        import com.example.demo.model.User;
        import com.example.demo.repository.UserRepository;
        import org.springframework.beans.factory.annotation.Autowired;
        import org.springframework.security.core.userdetails.UserDetails;
        import org.springframework.security.core.userdetails.UserDetailsService;
        import org.springframework.security.core.userdetails.UsernameNotFoundException;
        import org.springframework.stereotype.Service;

        @Service
        public class CustomUserDetailsService implements UserDetailsService {
            @Autowired
            private UserRepository userRepository;

            @Override
            public UserDetails loadUserByUsername(String username) throws UsernameNotFoundException {
                User user = userRepository.findByUsername(username);
                if (user == null) {
                    throw new UsernameNotFoundException("User not found.");
                }
                return new org.springframework.security.core.userdetails.User(user.getUsername(),
                        user.getPassword(), new ArrayList<>());
            }
        }
        
        

5.3 Creating Login Page HTML

Create an HTML file for the login page. Write the following code in src/main/resources/templates/login.html.

        
        <!DOCTYPE html>
        <html>
        <head>
            <title>Login</title>
        </head>
        <body>
            <h1>Login</h1>
            <form action="/login" method="post">
                <label for="username">Username:</label>
                <input type="text" id="username" name="username"><br>
                <label for="password">Password:</label>
                <input type="password" id="password" name="password"><br>
                <input type="submit" value="Login">
            </form>
            <div>
                <a href="/api/users/register">Register</a>
            </div>
        </body>
        </html>        
        
        

6. Running and Testing

Now that all settings are complete, let’s run the Spring Boot application.

6.1 Running the Application

Run the DemoApplication class from the IDE or start the application via command.

        
        mvn spring-boot:run
        
        

6.2 Testing User Registration

You can use API testing tools like Postman to test user registration. Let’s send a POST request like the following:

        
        POST /api/users/register
        Content-Type: application/json

        {
            "username": "testuser",
            "password": "password123",
            "email": "testuser@example.com"
        }
        
        

6.3 Testing Login

After registering, access the login page and enter the created user information to log in.

Conclusion

In this course, we have looked into how to develop a backend application using Spring Boot and implement login and user registration features utilizing Spring Security. You can apply these in real projects to add more advanced features or integrate with external APIs.

If you have any questions or need further assistance, please leave a comment. Thank you!

Spring Boot Backend Development Course, Implementing Login Logout with Spring Security, User Registration, Configuring Security

Hello, in this course, we will explore how to develop backend applications using Spring Boot, specifically focusing on implementing login and sign-up features utilizing Spring Security. This course is designed for both beginners and intermediate learners, and aims to facilitate understanding through practical exercises.

1. What is Spring Boot?

Spring Boot is a feature based on the Spring framework that helps you develop applications quickly without complex configurations. It automatically provides necessary configurations, thereby enhancing productivity and simplifying deployment.

1.1 Features of Spring Boot

  • Auto Configuration: Automatically provides necessary configurations without the developer needing to set them up.
  • Dependency Management: Easily manage required libraries through Maven or Gradle.
  • External Configuration: Allows for management of properties files externally, making it easy to change configurations based on the environment.
  • Standalone: Provides an embedded server, allowing the application to run without deploying it on a separate server.

2. What is Spring Security?

Spring Security is a powerful framework that provides authentication and authorization features for Spring applications. Using this library, you can easily implement login functionality, user role management, and security filtering.

2.1 Key Concepts of Spring Security

  • Authentication: Verifying user identity (login).
  • Authorization: Granting access rights to specific resources to authenticated users.
  • Security Filter Chain: A chain of filters to intercept requests and apply security policies.

3. Setting Up the Development Environment

To develop Spring Boot applications, you need to set up a basic development environment. Below are the necessary tools:

  • Java Development Kit (JDK) 11 or higher
  • IDE: IntelliJ IDEA, Eclipse, etc.
  • Maven or Gradle
  • Git (optional)

3.1 Project Structure


    my-spring-boot-app
    ├── src
    │   ├── main
    │   │   ├── java
    │   │   │   └── com
    │   │   │       └── example
    │   │   │           └── demo
    │   │   │               ├── DemoApplication.java
    │   │   │               └── security
    │   │   │                   └── SecurityConfig.java
    │   │   ├── resources
    │   │   │   ├── application.properties
    │   └── test
    └── pom.xml
    

4. Creating a Spring Boot Application

Follow the steps below to generate a Spring Boot application.

4.1 Using Spring Initializr

Access Spring Initializr and create a project with the following settings:

  • Project: Maven Project
  • Language: Java
  • Spring Boot: 2.5.4 (or the latest version)
  • Group: com.example
  • Artifact: demo
  • Dependencies: Spring Web, Spring Security, Spring Data JPA, H2 Database

4.2 Download the Generated Project and Open in IDE

Download the generated project zip file and open it in your IDE. You will see that the basic structure for a Spring Boot application has been set up.

5. Implementing Sign-Up Feature

Now, let’s implement the sign-up feature. We will set up a registration form and an endpoint for user login.

5.1 Creating Sign-Up DTO


    package com.example.demo.dto;

    public class SignUpDto {
        private String username;
        private String password;
        private String email;

        // Getters and Setters
    }
    

5.2 Creating Sign-Up Service


    package com.example.demo.service;

    import com.example.demo.dto.SignUpDto;
    import com.example.demo.entity.User;

    public interface UserService {
        User registerNewUserAccount(SignUpDto signUpDto);
    }
    

5.3 Creating User Entity


    package com.example.demo.entity;

    import javax.persistence.*;

    @Entity
    public class User {
        @Id
        @GeneratedValue(strategy = GenerationType.IDENTITY)
        private Long id;

        private String username;
        private String password;

        @Column(unique = true)
        private String email;

        // Getters and Setters
    }
    

6. Configuring Spring Security

We will configure Spring Security to implement user authentication and role management.

6.1 Creating SecurityConfig Class


    package com.example.demo.security;

    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    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;

    @Configuration
    @EnableWebSecurity
    public class SecurityConfig extends WebSecurityConfigurerAdapter {
        @Override
        protected void configure(HttpSecurity http) throws Exception {
            http
                .csrf().disable()
                .authorizeRequests()
                .antMatchers("/signup", "/").permitAll()
                .anyRequest().authenticated()
                .and()
                .formLogin()
                .loginPage("/login")
                .permitAll()
                .and()
                .logout()
                .permitAll();
        }
    }
    

6.2 Implementing Login and Logout Endpoints


    package com.example.demo.controller;

    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.GetMapping;

    @Controller
    public class AuthController {

        @GetMapping("/login")
        public String login() {
            return "login";
        }

        @GetMapping("/signup")
        public String signup() {
            return "signup";
        }
    }
    

7. Conclusion

In this course, we learned how to develop a simple backend application using Spring Boot and implement user authentication and sign-up features with Spring Security. You can apply this knowledge in real projects and further enhance your understanding through practical exercises.

Additional References