Merge pull request #152 from bounswe/issue#150-create-post

Implement Post CRUD Operations and Tag-based Filtering

backend/demo-group7/pom.xml

@@ -61,6 +61,12 @@
 			<version>1.18.34</version>
 			<scope>provided</scope>
 		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-devtools</artifactId>
+		</dependency>
+
 	</dependencies>
 
 	<build>

backend/demo-group7/src/main/java/com/group7/demo/controllers/AuthenticationController.java

@@ -18,14 +18,10 @@ public class AuthenticationController {
     private final AuthenticationService authenticationService;
 
     @PostMapping("/register")
-    public ResponseEntity<String> register(@RequestBody RegisterRequest request) {
-        try {
-            User registeredUser = authenticationService.register(request);
-            // TODO: can create and return session token on signing up.
-            return ResponseEntity.status(HttpStatus.CREATED).body(null);
-        } catch (Exception e) {
-            return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(e.getMessage());
-        }
+    public ResponseEntity<String> register(@RequestBody RegisterRequest request) throws Exception {
+        User registeredUser = authenticationService.register(request);
+        // TODO: can create and return session token on signing up.
+        return ResponseEntity.status(HttpStatus.CREATED).body(null);
     }
 
     @PostMapping("/login")

backend/demo-group7/src/main/java/com/group7/demo/controllers/PostController.java

@@ -0,0 +1,54 @@
+package com.group7.demo.controllers;
+
+import com.group7.demo.dtos.PostRequest;
+import com.group7.demo.dtos.PostResponse;
+import com.group7.demo.models.Post;
+import com.group7.demo.services.PostService;
+import lombok.AllArgsConstructor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+import java.util.Set;
+
+@RestController
+@RequestMapping("/api/posts")
+@AllArgsConstructor
+public class PostController {
+    private PostService postService;
+
+    @PostMapping
+    public ResponseEntity<PostResponse> createPost(@RequestBody PostRequest postRequest) {
+        PostResponse createdPost = postService.createPost(postRequest);
+        return ResponseEntity.ok(createdPost);
+    }
+
+    @GetMapping
+    public ResponseEntity<List<PostResponse>> fetchPosts(
+            @RequestParam(required = false) Set<String> tags) {
+
+        List<PostResponse> posts;
+
+        if (tags != null) {
+            posts = postService.getPostsByTags(tags);
+            return ResponseEntity.ok(posts);
+        } else {
+            posts = postService.getAllPosts();
+        }
+
+        return ResponseEntity.ok(posts);
+    }
+
+    @DeleteMapping("/{postId}")
+    public ResponseEntity<String> deletePost(@PathVariable Long postId) {
+        postService.deletePost(postId);
+        return ResponseEntity.ok("Post deleted successfully.");
+    }
+
+//    @GetMapping("/by-tags")
+//    public ResponseEntity<List<PostResponse>> getPostsByTags(@RequestParam ) {
+//
+//    }
+}
+

backend/demo-group7/src/main/java/com/group7/demo/dtos/PostRequest.java

@@ -0,0 +1,16 @@
+package com.group7.demo.dtos;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import java.util.Set;
+
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+public class PostRequest {
+
+    private String content;
+    private Set<String> tags;
+}

backend/demo-group7/src/main/java/com/group7/demo/dtos/PostResponse.java

@@ -0,0 +1,19 @@
+package com.group7.demo.dtos;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import java.time.LocalDateTime;
+import java.util.Set;
+
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+public class PostResponse {
+
+    private Long id;
+    private String content;
+    private Set<String> tags;
+    private LocalDateTime createdAt;
+}

backend/demo-group7/src/main/java/com/group7/demo/exceptions/ErrorResponse.java

@@ -0,0 +1,41 @@
+package com.group7.demo.exceptions;
+
+import java.time.LocalDateTime;
+
+public class ErrorResponse {
+
+    private LocalDateTime timestamp;
+    private String message;
+    private String details;
+
+    public ErrorResponse(LocalDateTime timestamp, String message, String details) {
+        this.timestamp = timestamp;
+        this.message = message;
+        this.details = details;
+    }
+
+    // Getters and Setters
+    public LocalDateTime getTimestamp() {
+        return timestamp;
+    }
+
+    public void setTimestamp(LocalDateTime timestamp) {
+        this.timestamp = timestamp;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+
+    public void setMessage(String message) {
+        this.message = message;
+    }
+
+    public String getDetails() {
+        return details;
+    }
+
+    public void setDetails(String details) {
+        this.details = details;
+    }
+}

backend/demo-group7/src/main/java/com/group7/demo/exceptions/handler/GlobalExceptionHandler.java

@@ -0,0 +1,50 @@
+package com.group7.demo.exceptions.handler;
+
+import com.group7.demo.exceptions.ErrorResponse;
+import jakarta.persistence.EntityNotFoundException;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.context.request.WebRequest;
+
+import java.time.LocalDateTime;
+import java.util.HashMap;
+import java.util.Map;
+
+@ControllerAdvice
+public class GlobalExceptionHandler {
+
+    // Handle generic exceptions
+    @ExceptionHandler(Exception.class)
+    public ResponseEntity<ErrorResponse> handleGlobalException(Exception ex, WebRequest request) {
+        ErrorResponse errorResponse = new ErrorResponse(
+                LocalDateTime.now(),
+                "An unexpected error occurred",
+                ex.getMessage()
+        );
+        return new ResponseEntity<>(errorResponse, HttpStatus.INTERNAL_SERVER_ERROR);
+    }
+
+
+    @ExceptionHandler(IllegalArgumentException.class)
+    public ResponseEntity<Object> handleIllegalArgumentException(IllegalArgumentException ex, WebRequest request) {
+        Map<String, Object> body = new HashMap<>();
+        body.put("timestamp", LocalDateTime.now());
+        body.put("message", ex.getMessage());
+
+        return new ResponseEntity<>(body, HttpStatus.BAD_REQUEST);
+    }
+
+    @ExceptionHandler(EntityNotFoundException.class)
+    public ResponseEntity<Object> handleEntityNotFoundException(EntityNotFoundException ex, WebRequest request) {
+        Map<String, Object> body = new HashMap<>();
+        body.put("timestamp", LocalDateTime.now());
+        body.put("message", ex.getMessage());
+
+        return new ResponseEntity<>(body, HttpStatus.NOT_FOUND);
+    }
+
+
+
+}

backend/demo-group7/src/main/java/com/group7/demo/models/Post.java

@@ -0,0 +1,34 @@
+package com.group7.demo.models;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import jakarta.persistence.*;
+import lombok.*;
+
+import java.time.LocalDateTime;
+import java.util.HashSet;
+import java.util.Set;
+
+@Data
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+@Entity
+@EqualsAndHashCode(exclude = "tags")  // Avoid using tags in equals and hashCode to prevent recursion
+public class Post {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    private String content;
+
+    private LocalDateTime createdAt;
+
+    @ManyToMany
+    @JoinTable(
+            name = "post_tags",
+            joinColumns = @JoinColumn(name = "post_id"),
+            inverseJoinColumns = @JoinColumn(name = "tag_name"))
+//    @JsonIgnoreProperties("posts")  // Prevents infinite recursion with Tag entity
+    private Set<Tag> tags = new HashSet<>();
+}

backend/demo-group7/src/main/java/com/group7/demo/models/Tag.java

@@ -0,0 +1,27 @@
+package com.group7.demo.models;
+
+import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToMany;
+import lombok.*;
+
+import java.util.HashSet;
+import java.util.Set;
+
+
+@Data
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+@Entity
+@EqualsAndHashCode(exclude = "posts")  // Avoid using posts in equals and hashCode to prevent recursion
+public class Tag {
+
+    @Id
+    private String name;
+
+    @ManyToMany(mappedBy = "tags")
+//    @JsonIgnoreProperties("tags")  // Prevents infinite recursion with Post entity
+    private Set<Post> posts = new HashSet<>();
+}

backend/demo-group7/src/main/java/com/group7/demo/repository/PostRepository.java

@@ -0,0 +1,22 @@
+package com.group7.demo.repository;
+
+import com.group7.demo.dtos.PostResponse;
+import com.group7.demo.models.Post;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import java.util.List;
+import java.util.Set;
+
+public interface PostRepository extends JpaRepository<Post, Long> {
+    List<Post> findByTags_Name(String tagName);
+
+    @Query("SELECT p.id, p.content, p.createdAt, t.name FROM Post p LEFT JOIN p.tags t")
+    List<Object[]> findAllPostDataWithTags();
+
+    @Query("SELECT DISTINCT p FROM Post p LEFT JOIN FETCH p.tags")
+    List<Post> findAllPostsWithTags();
+
+
+}

backend/demo-group7/src/main/java/com/group7/demo/repository/TagRepository.java

@@ -0,0 +1,10 @@
+package com.group7.demo.repository;
+
+import com.group7.demo.models.Tag;
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import java.util.Optional;
+
+public interface TagRepository extends JpaRepository<Tag, Long> {
+    Optional<Tag> findByName(String name);
+}