Golang 实现简易论坛系统设计

type Post struct {
    ID        int       `json:"id"`
    Title     string    `json:"title"`
    Content   string    `json:"content"`
    Author    string    `json:"author"` // 可替换为 user_id
    CreatedAt time.Time `json:"created_at"`
}
type Comment struct {
ID        int       json:"id"
PostID    int       json:"post_id"
Content   string    json:"content"
Author    string    json:"author"
CreatedAt time.Time json:"created_at"
}

func main() {
    http.HandleFunc("/posts", listPosts)
    http.HandleFunc("/posts", createPost) // 区分 POST 和 GET
    http.HandleFunc("/posts/", getPostWithComments)
    log.Println("Server starting on :8080")
    http.ListenAndServe(":8080", nil)
}

var posts []Post
var currentID = 1
var mu sync.Mutex
func createPost(w http.ResponseWriter, r *http.Request) {
if r.Method != "POST" {
http.Error(w, "method not allowed", 405)
return
}
var req struct {
    Title   string `json:"title"`
    Content string `json:"content"`
    Author  string `json:"author"`
}

if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
    http.Error(w, "bad request", 400)
    return
}

mu.Lock()
defer mu.Unlock()

posts = append(posts, Post{
    ID:        currentID,
    Title:     req.Title,
    Content:   req.Content,
    Author:    req.Author,
    CreatedAt: time.Now(),
})
currentID++

w.Header().Set("Content-Type", "application/json")
json.NewEncoder(w).Encode(map[string]int{"id": currentID - 1})
}

var comments []Comment
var commentID = 1
func addComment(w http.ResponseWriter, r *http.Request) {
// 提取 postID
parts := strings.Split(r.URL.Path, "/")
postID, _ := strconv.Atoi(parts[2])
// 检查帖子是否存在
exists := false
for _, p := range posts {
    if p.ID == postID {
        exists = true
        break
    }
}
if !exists {
    http.Error(w, "post not found", 404)
    return
}

var req struct{ Content, Author string }
json.NewDecoder(r.Body).Decode(&req)

mu.Lock()
defer mu.Unlock()

comments = append(comments, Comment{
    ID:        commentID,
    PostID:    postID,
    Content:   req.Content,
    Author:    req.Author,
    CreatedAt: time.Now(),
})
commentID++

w.WriteHeader(201)
json.NewEncoder(w).Encode(map[string]int{"comment_id": commentID - 1})
}