Hello! In this article, we will take a detailed look at how to perform backend development<\/strong> using Spring Boot<\/strong>. In particular, we will cover how to implement user authentication using OAuth2<\/strong> and how to add author information to posts created by users.<\/p>\n Spring Boot is a framework<\/strong> that minimizes complex setup and enables rapid application development. It is based on the Spring framework and includes commonly used libraries and configurations, allowing for very efficient development of web applications.<\/p>\n OAuth2<\/strong> is an authentication and authorization protocol<\/strong> that helps resource owners grant third-party applications access to their resources. It makes it easy to implement user authentication in various environments, such as web applications and mobile applications.<\/p>\n To start developing a project using Spring Boot, we will use Spring Initializr<\/strong>. Please select the following dependencies:<\/p>\n After creating the project, add the necessary libraries through Maven or Gradle.<\/p>\n Configure the client information for the external service (e.g., Google, GitHub, etc.) that will use OAuth2 in the Configure Spring Security to implement the OAuth2 login feature.<\/p>\n Create a custom login page using HTML and CSS. Here is an example:<\/p>\n To configure the logout functionality, modify the Now, we will implement the functionality to save posts created by users in the database.<\/p>\n Create an Entity class for the post (including the author).<\/p>\n Create Repository and Service classes for writing posts.<\/p>\n Create a Controller so that users can write and view posts.<\/p>\n In this article, we discussed the basics of backend development using Spring Boot and how to implement user authentication and writing functionality using OAuth2. OAuth2 allows for easy implementation of various social media login features, which will be a great help in developing user-friendly web applications. In the next course, we will cover integration with the front end and, further, deployment. I hope this article has been helpful, and if you have any questions, please feel free to leave a comment!<\/p>\n <\/body><\/p>\n","protected":false},"excerpt":{"rendered":"1. What is Spring Boot?<\/h2>\n
1.1. Advantages of Spring Boot<\/h3>\n
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2. What is OAuth2?<\/h2>\n
2.1. Key Components of OAuth2<\/h3>\n
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3. Project Setup<\/h2>\n
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3.1. Adding Key Dependencies (Example of pom.xml)<\/h3>\n
\n<dependencies>\n <dependency>\n <groupId>org.springframework.boot<\/groupId>\n <artifactId>spring-boot-starter-web<\/artifactId>\n <\/dependency>\n <dependency>\n <groupId>org.springframework.boot<\/groupId>\n <artifactId>spring-boot-starter-security<\/artifactId>\n <\/dependency>\n <dependency>\n <groupId>org.springframework.boot<\/groupId>\n <artifactId>spring-boot-starter-data-jpa<\/artifactId>\n <\/dependency>\n <dependency>\n <groupId>com.h2database<\/groupId>\n <artifactId>h2<\/artifactId>\n <scope>runtime<\/scope>\n <\/dependency>\n <dependency>\n <groupId>org.springframework.security.oauth.boot<\/groupId>\n <artifactId>spring-security-oauth2-autoconfigure<\/artifactId>\n <\/dependency>\n<\/dependencies>\n<\/code><\/pre>\n4. OAuth2 Configuration for User Authentication<\/h2>\n
4.1. application.yml Configuration<\/h3>\n
application.yml<\/code> file.<\/p>\n\nspring:\n security:\n oauth2:\n client:\n registration:\n google:\n client-id: YOUR_CLIENT_ID\n client-secret: YOUR_CLIENT_SECRET\n scope: profile, email\n provider:\n google:\n authorization-uri: https:\/\/accounts.google.com\/o\/oauth2\/auth\n token-uri: https:\/\/oauth2.googleapis.com\/token\n user-info-uri: https:\/\/www.googleapis.com\/userinfo\/v2\/me\n<\/code><\/pre>\n4.2. Setting Up Security Configuration<\/h3>\n
\nimport org.springframework.context.annotation.Configuration;\nimport org.springframework.security.config.annotation.web.builders.HttpSecurity;\nimport org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;\nimport org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;\n\n@Configuration\n@EnableWebSecurity\npublic class SecurityConfig extends WebSecurityConfigurerAdapter {\n @Override\n protected void configure(HttpSecurity http) throws Exception {\n http\n .authorizeRequests(authorizeRequests ->\n authorizeRequests\n .antMatchers(\"\/\", \"\/login\", \"\/perform_login\").permitAll()\n .anyRequest().authenticated()\n )\n .oauth2Login(oauth2 -> oauth2\n .loginPage(\"\/login\")\n );\n }\n}\n<\/code><\/pre>\n5. Implementing Login and Logout Features<\/h2>\n
5.1. Creating a Custom Login Page<\/h3>\n
\n<!DOCTYPE html>\n<html lang=\"en\">\n<head>\n <meta charset=\"UTF-8\">\n <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n <title>Login Page<\/title>\n<\/head>\n<body>\n <h1>Login Page<\/h1>\n <a href=\"\/oauth2\/authorization\/google\">Login with Google<\/a>\n<\/body>\n<\/html>\n<\/code><\/pre>\n5.2. Handling Logout<\/h3>\n
SecurityConfig<\/code> as follows.<\/p>\n\n@Override\nprotected void configure(HttpSecurity http) throws Exception {\n http\n .authorizeRequests(authorizeRequests ->\n authorizeRequests\n .antMatchers(\"\/\", \"\/login\", \"\/perform_login\").permitAll()\n .anyRequest().authenticated()\n )\n .oauth2Login(oauth2 -> oauth2\n .loginPage(\"\/login\")\n )\n .logout(logout -> logout\n .logoutUrl(\"\/logout\")\n .logoutSuccessUrl(\"\/login?logout\")\n );\n}\n<\/code><\/pre>\n6. Implementing the Writing Feature<\/h2>\n
6.1. Creating the Entity Class<\/h3>\n
\nimport javax.persistence.*;\n\n@Entity\npublic class Post {\n @Id\n @GeneratedValue(strategy = GenerationType.IDENTITY)\n private Long id;\n\n private String title;\n private String content;\n\n @ManyToOne\n @JoinColumn(name = \"author_id\")\n private User author;\n\n \/\/ Getters and Setters\n}\n<\/code><\/pre>\n6.2. Creating the User Entity<\/h3>\n
\nimport javax.persistence.*;\n\n@Entity\npublic class User {\n @Id\n @GeneratedValue(strategy = GenerationType.IDENTITY)\n private Long id;\n\n private String username;\n private String email;\n\n \/\/ Getters and Setters\n}\n<\/code><\/pre>\n6.3. Creating Repository and Service<\/h3>\n
\n\/\/ PostRepository.java\nimport org.springframework.data.jpa.repository.JpaRepository;\n\npublic interface PostRepository extends JpaRepository<Post, Long> {\n}\n\n\/\/ PostService.java\nimport org.springframework.beans.factory.annotation.Autowired;\nimport org.springframework.stereotype.Service;\n\nimport java.util.List;\n\n@Service\npublic class PostService {\n @Autowired\n private PostRepository postRepository;\n\n public List<Post> findAll() {\n return postRepository.findAll();\n }\n\n public Post save(Post post) {\n return postRepository.save(post);\n }\n}\n<\/code><\/pre>\n6.4. Creating the Controller<\/h3>\n
\nimport org.springframework.beans.factory.annotation.Autowired;\nimport org.springframework.web.bind.annotation.*;\n\nimport java.util.List;\n\n@RestController\n@RequestMapping(\"\/posts\")\npublic class PostController {\n @Autowired\n private PostService postService;\n\n @GetMapping\n public List<Post> getAllPosts() {\n return postService.findAll();\n }\n\n @PostMapping\n public Post createPost(@RequestBody Post post) {\n return postService.save(post);\n }\n}\n<\/code><\/pre>\n7. Conclusion<\/h2>\n