Add tag module with post associations

src/main/java/com/openisle/controller/PostController.java

@@ -38,7 +38,8 @@ public class PostController {
         if (captchaEnabled && postCaptchaEnabled && !captchaService.verify(req.getCaptcha())) {
             return ResponseEntity.badRequest().build();
         }
-        Post post = postService.createPost(auth.getName(), req.getCategoryId(), req.getTitle(), req.getContent());
+        Post post = postService.createPost(auth.getName(), req.getCategoryId(),
+                req.getTitle(), req.getContent(), req.getTagIds());
         return ResponseEntity.ok(toDto(post));
     }
 
@@ -69,6 +70,7 @@ public class PostController {
         dto.setCreatedAt(post.getCreatedAt());
         dto.setAuthor(post.getAuthor().getUsername());
         dto.setCategory(post.getCategory().getName());
+        dto.setTags(post.getTags().stream().map(com.openisle.model.Tag::getName).collect(Collectors.toList()));
         dto.setViews(post.getViews());
 
         List<ReactionDto> reactions = reactionService.getReactionsForPost(post.getId())
@@ -130,6 +132,7 @@ public class PostController {
         private Long categoryId;
         private String title;
         private String content;
+        private java.util.List<Long> tagIds;
         private String captcha;
     }
 
@@ -141,6 +144,7 @@ public class PostController {
         private LocalDateTime createdAt;
         private String author;
         private String category;
+        private java.util.List<String> tags;
         private long views;
         private List<CommentDto> comments;
         private List<ReactionDto> reactions;

src/main/java/com/openisle/controller/TagController.java

@@ -0,0 +1,58 @@
+package com.openisle.controller;
+
+import com.openisle.model.Tag;
+import com.openisle.service.TagService;
+import lombok.Data;
+import lombok.RequiredArgsConstructor;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+@RestController
+@RequestMapping("/api/tags")
+@RequiredArgsConstructor
+public class TagController {
+    private final TagService tagService;
+
+    @PostMapping
+    public TagDto create(@RequestBody TagRequest req) {
+        Tag tag = tagService.createTag(req.getName());
+        return toDto(tag);
+    }
+
+    @DeleteMapping("/{id}")
+    public void delete(@PathVariable Long id) {
+        tagService.deleteTag(id);
+    }
+
+    @GetMapping
+    public List<TagDto> list() {
+        return tagService.listTags().stream()
+                .map(this::toDto)
+                .collect(Collectors.toList());
+    }
+
+    @GetMapping("/{id}")
+    public TagDto get(@PathVariable Long id) {
+        return toDto(tagService.getTag(id));
+    }
+
+    private TagDto toDto(Tag tag) {
+        TagDto dto = new TagDto();
+        dto.setId(tag.getId());
+        dto.setName(tag.getName());
+        return dto;
+    }
+
+    @Data
+    private static class TagRequest {
+        private String name;
+    }
+
+    @Data
+    private static class TagDto {
+        private Long id;
+        private String name;
+    }
+}