Initial commit of frontend and backend project

.gitignore

+# Go 忽略项
+*.exe          # Windows 可执行文件
+*.dll          # Windows 动态链接库
+*.so           # Linux 共享库
+*.dylib        # macOS 动态库
+*.test         # Go 测试可执行文件
+*.prof         # Go Profiling 文件
+
+# Go Module 依赖
+/vendor/
+
+# 本地开发工具或IDE文件 (根据你使用的工具添加)
+.vscode/
+.idea/
+*.sublime-project
+*.sublime-workspace
+
+# 数据库文件 - 极其重要！不要提交数据库文件
+comments.db
+*.db

前端/app.js

+document.addEventListener('DOMContentLoaded', () => {
+    // 修复变量名和对应的HTML ID
+    const userNameInput = document.getElementById('username'); 
+    const commentContentInput = document.getElementById('comment-text'); 
+    const submitBtn = document.getElementById('submit-comment'); 
+
+    const prevPageBtn = document.getElementById('prev-page');
+    const nextPageBtn = document.getElementById('next-page'); 
+    const currentPageSpan = document.getElementById('current-page'); 
+    const pageSizeSelect = document.getElementById('pageSizeSelect'); 
+
+    const commentsList = document.getElementById('comments-list');
+
+    const API_HOST = 'http://localhost:8080'; 
+    
+    let currentPage = 1;
+    let pageSize = parseInt(pageSizeSelect.value, 10);
+    let totalComments = 0;
+
+    async function fetchComments() {
+        try {
+            const response = await fetch(`${API_HOST}/comment/get?page=${currentPage}&size=${pageSize}`);
+            if (!response.ok) {
+                throw new Error(`HTTP error: ${response.status}`);
+            }
+            const result = await response.json();
+
+            if (result.code === 0) { 
+                renderComments(result.data.comments);
+                totalComments = result.data.total;
+                updatePaginationControls();
+            } else {
+                commentsList.innerHTML = `<p>加载评论失败: ${escapeHTML(result.msg)}</p>`; // 显示错误信息
+                totalComments = 0; 
+                updatePaginationControls(); 
+                alert(`无法加载评论: ${result.msg}`);
+            }
+        } catch (error) {
+            console.error('加载评论错误: ', error);
+            commentsList.innerHTML = '<p>加载评论出错，请检查服务器是否运行。</p>'; 
+            totalComments = 0; 
+            updatePaginationControls(); 
+            alert('无法加载评论，请检查后端服务器是否正常运行？');
+        }
+    }
+
+    function renderComments(comments = []) {
+        commentsList.innerHTML = '';
+
+        if (!comments || comments.length === 0) {
+            commentsList.innerHTML = '<p>暂无评论。</p>';
+            return;
+        }
+
+        comments.forEach(comment => {
+            const commentItem = document.createElement('div');
+            commentItem.classList.add('comment-item');
+            commentItem.dataset.id = comment.id;
+
+            commentItem.innerHTML = `
+                <span class="user-name">${escapeHTML(comment.name)}</span>
+                <p class="comment-text">${escapeHTML(comment.content)}</p>
+                <button class="delete-btn">删除</button>
+            `;
+            commentsList.appendChild(commentItem);
+        });
+    }
+
+    async function addComment() {
+        const userName = userNameInput.value.trim();
+        const content = commentContentInput.value.trim();
+
+        if (!userName || !content) {
+            alert('用户名和评论内容不能为空');
+            return;
+        }
+
+        try {
+            const response = await fetch(`${API_HOST}/comment/add`, {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/json',
+                },
+                body: JSON.stringify({ name: userName, content: content }),
+            });
+
+            if (!response.ok) {
+                throw new Error(`HTTP error: ${response.status}`);
+            }
+            const result = await response.json();
+
+            if (result.code === 0) { 
+                currentPage = 1; 
+                fetchComments(); 
+                userNameInput.value = '';
+                commentContentInput.value = '';
+            } else {
+                alert(`添加评论失败: ${result.msg}`);
+            }
+        } catch (error) {
+            console.error('添加评论错误', error);
+            alert('添加评论出错');
+        }
+    }
+
+    async function handleDelete(event) {
+        if (event.target.classList.contains('delete-btn')) {
+            const commentItem = event.target.closest('.comment-item');
+            if (commentItem) {
+                const commentId = commentItem.dataset.id;
+                if (confirm(`确定要删除ID为 ${commentId} 的评论吗？`)) {
+                    try {
+                        const response = await fetch(`${API_HOST}/comment/delete?id=${commentId}`, {
+                            method: 'POST', 
+                        });
+                        if (!response.ok) {
+                             // 对于非2xx状态码，尝试读取后端返回的错误信息
+                            const errorData = await response.json().catch(() => ({ msg: `HTTP status ${response.status}` }));
+                            throw new Error(`删除失败: ${errorData.msg || `HTTP status ${response.status}`}`);
+                        }
+                        const result = await response.json();
+
+                        if (result.code === 0) {
+                            fetchComments(); 
+                        } else {
+                            alert(`删除失败: ${result.msg}`);
+                        }
+                    } catch (error) {
+                        console.error('删除评论错误', error);
+                        alert(`删除评论出错: ${error.message}`); 
+                    }
+                }
+            }
+        }
+    }
+
+    function updatePaginationControls() {
+        currentPageSpan.textContent = `Page: ${currentPage}`;
+        
+        const maxPage = (pageSize === -1 || totalComments === 0) ? 1 : Math.ceil(totalComments / pageSize);
+
+        prevPageBtn.disabled = currentPage <= 1; 
+        nextPageBtn.disabled = currentPage >= maxPage; 
+
+        if (pageSize === -1) { 
+             prevPageBtn.disabled = true;
+             nextPageBtn.disabled = true;
+        }
+    }
+
+    function escapeHTML(str) {
+        const div = document.createElement('div');
+        div.appendChild(document.createTextNode(str));
+        return div.innerHTML;
+    }
+
+
+    if(submitBtn) submitBtn.addEventListener('click', addComment);
+    if(commentsList) commentsList.addEventListener('click', handleDelete);
+    
+    if(prevPageBtn) {
+        prevPageBtn.addEventListener('click', () => {
+            if (currentPage > 1) {
+                currentPage--;
+                fetchComments();
+            }
+        });
+    }
+
+    if(nextPageBtn) {
+        nextPageBtn.addEventListener('click', () => {
+            const maxPage = (pageSize === -1 || totalComments === 0) ? 1 : Math.ceil(totalComments / pageSize);
+            if (currentPage < maxPage || pageSize === -1) { 
+                 if (pageSize === -1 && currentPage === 1) {
+                     // 如果是显示全部模式且在第一页，点击下一页不应该有反应
+                     return;
+                 }
+                 if (pageSize !== -1 && currentPage >= maxPage) {
+                     // 如果不是显示全部模式且已经是最后一页，不应该有反应
+                     return;
+                 }
+
+                currentPage++;
+                fetchComments();
+            }
+        });
+    }
+
+    if(pageSizeSelect) {
+        pageSizeSelect.addEventListener('change', (event) => {
+            pageSize = parseInt(event.target.value, 10);
+            currentPage = 1;
+            fetchComments();
+        });
+    }
+
+
+    fetchComments();
+});
\ No newline at end of file

前端/index.html

+<!doctype html>
+<html lang="zh-CN">
+
+<head>
+    <meta charset="utf-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>简易评论区</title>
+    <link rel="stylesheet" href="style.css" />
+</head>
+
+<body>
+    <div class="container">
+        <div class="comment-input-area">
+            <div class="form-group">
+                <label for="userName">用户名</label>
+                <input type="text" id="username" placeholder="用户名" />
+            </div>
+            <div class="form-group">
+                <label for="commentContent">评论内容</label>
+                <textarea id="comment-text" placeholder="说点什么吧..." rows="4"></textarea>
+            </div>
+            <button id="submit-comment">提交</button>
+        </div>
+        
+        <div id="comments-list" class="comments-list">
+        </div>
+        
+        <div class="pagination">
+            <button id="prev-page" disabled>上一页</button>
+            <span id="current-page">Page: 1</span>
+            <button id="next-page">下一页</button>
+            <select id="pageSizeSelect">
+                <option value="5">5 per page</option>
+                <option value="10" selected>10 per page</option>
+                <option value="20">20 per page</option>
+                <option value="-1">Show All</option>
+            </select>
+        </div>
+    </div>
+
+    <script src="app.js"></script>
+</body>
+
+</html>
\ No newline at end of file

前端/style.css

+body {
+    font-family: sans-serif;
+    margin: 0;
+    padding: 20px;
+    background-color: #f4f6f8;
+    color: #333;
+    display: flex;
+    justify-content: center;
+}
+
+.container {
+    background-color: #fff;
+    padding: 20px;
+    margin-bottom: 20px;
+    border-radius: 8px;
+    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
+    width: 500px;
+}
+
+.comment-input-area {
+    background-color: #e0e5ea;
+    padding: 15px;
+    border-radius: 5px;
+    margin-bottom: 20px;
+}
+
+.comment-input-area div {
+    margin-bottom: 10px;
+}
+
+.comment-input-area label {
+    display: block;
+    margin-bottom: 5px;
+    font-weight: bold;
+    font-size: 0.9em;
+}
+
+.comment-input-area input[type="text"],
+.comment-input-area textarea {
+    width: calc(100% - 12px);
+    padding: 8px;
+    border: 1px solid #ccc;
+    border-radius: 4px;
+    box-sizing: border-box;
+}
+
+.comment-input-area textarea {
+    min-height: 80px;
+    resize: vertical;
+}
+
+.comment-input-area button {
+    background-color: #343a40;
+    color: white;
+    border: none;
+    padding: 10px 15px;
+    border-radius: 4px;
+    cursor: pointer;
+    float: right;
+}
+
+.comment-input-area button:hover {
+    background-color: #23272b;
+}
+
+
+.comment-input-area::after {
+    content: "";
+    clear: both;
+    display: table;
+}
+
+.pagination {
+    margin-top: 20px;
+    text-align: center;
+}
+
+.pagination button,
+.pagination select {
+    padding: 8px 12px;
+    margin: 0 5px;
+    border: 1px solid #ccc;
+    border-radius: 4px;
+    cursor: pointer;
+}
+
+.pagination button:disabled {
+    cursor: not-allowed;
+    opacity: 0.5;
+}
+
+.pagination span {
+    margin: 0 10px;
+}
+
+.comments-list .comment-item {
+    border-left: 3px solid #000;
+    padding-left: 15px;
+    margin-bottom: 20px;
+    position: relative;
+}
\ No newline at end of file

后端/go.mod

+module xlab.zju.edu.cn/git/melonmusk/first-project-comment
+
+go 1.24.3
+
+require github.com/mattn/go-sqlite3 v1.14.28 // indirect

后端/go.sum

+github.com/mattn/go-sqlite3 v1.14.28 h1:ThEiQrnbtumT+QMknw63Befp/ce/nUPgBPMlRFEum7A=
+github.com/mattn/go-sqlite3 v1.14.28/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=

后端/main.go

+package main
+
+import (
+	"database/sql"
+	"encoding/json"
+	"log"
+	"net/http"
+	"strconv"
+	"sync"
+	"time"
+
+	_ "github.com/mattn/go-sqlite3"
+)
+
+type UnifiedResponse struct {
+	Code int         `json:"code"`
+	Msg  string      `json:"msg"`
+	Data interface{} `json:"data"`
+}
+
+type Comment struct {
+	ID        int       `json:"id"`
+	Name      string    `json:"name"`
+	Content   string    `json:"content"`
+	CreatedAt time.Time `json:"created_at"`
+}
+
+type AddCommentRequest struct {
+	Name    string `json:"name"`
+	Content string `json:"content"`
+}
+
+type GetCommentsData struct {
+	Total    int       `json:"total"`
+	Comments []Comment `json:"comments"`
+}
+
+var (
+	comments      = make([]Comment, 0)
+	mutex         = &sync.RWMutex{}
+	nextCommentID = 1
+)
+
+var db *sql.DB
+
+func initDB(dataSourceName string) (*sql.DB, error) {
+	var err error
+	// 打开数据库连接 (如果文件不存在会创建)
+	// dataSourceName 通常是数据库文件的路径
+	db, err = sql.Open("sqlite3", dataSourceName)
+	if err != nil {
+		log.Printf("Error opening database: %v", err)
+		return nil, err
+	}
+
+	// 检查连接是否有效
+	if err = db.Ping(); err != nil {
+		db.Close() // 确保关闭连接
+		log.Printf("Error connecting to database: %v", err)
+		return nil, err
+	}
+
+	// 创建 comments 表 (如果不存在)
+	createTableSQL := `
+	CREATE TABLE IF NOT EXISTS comments (
+		id INTEGER PRIMARY KEY AUTOINCREMENT,
+		name TEXT NOT NULL,
+		content TEXT NOT NULL,
+		created_at DATETIME DEFAULT CURRENT_TIMESTAMP
+	);`
+	_, err = db.Exec(createTableSQL)
+	if err != nil {
+		db.Close() // 确保关闭连接
+		log.Printf("Error creating comments table: %v", err)
+		return nil, err
+	}
+
+	log.Printf("Database initialized successfully.")
+	return db, nil
+}
+
+func sendJSONResponse(w http.ResponseWriter, statusCode int, data UnifiedResponse) {
+	w.Header().Set("Content-Type", "application/json")
+
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+	w.Header().Set("Access-Control-Allow-Methods", "GET, POST, OPTIONS, DELETE")
+	w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+
+	w.WriteHeader(statusCode)
+	if err := json.NewEncoder(w).Encode(data); err != nil {
+		log.Printf("JSON error: %v", err)
+	}
+}
+
+/*
+func getCommentsHandler(w http.ResponseWriter, r *http.Request) {
+	if r.Method == http.MethodOptions {
+		sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "OPTIONS OK"})
+		return
+	}
+	if r.Method != http.MethodGet {
+		sendJSONResponse(w, http.StatusMethodNotAllowed, UnifiedResponse{Code: 1, Msg: "invalid method"})
+		return
+	}
+
+	pageStr := r.URL.Query().Get("page")
+	sizeStr := r.URL.Query().Get("size")
+
+	page, err := strconv.Atoi(pageStr)
+	if err != nil || page < 1 {
+		page = 1
+	}
+
+	size, err := strconv.Atoi(sizeStr)
+	if err != nil || size == 0 {
+		size = 10
+	}
+
+	mutex.RLock()
+	defer mutex.RUnlock()
+
+	var commentsToReturn []Comment
+	total := len(comments)
+
+	if size == -1 {
+		commentsToReturn = make([]Comment, total)
+		copy(commentsToReturn, comments)
+	} else if total > 0 {
+		start := (page - 1) * size
+		end := start + size
+
+		if start < 0 {
+			start = 0
+		}
+
+		if start >= total {
+			commentsToReturn = []Comment{}
+		} else {
+			if end > total {
+				end = total
+			}
+			commentsToReturn = make([]Comment, end-start)
+			copy(commentsToReturn, comments[start:end])
+		}
+	} else {
+		commentsToReturn = []Comment{}
+	}
+
+	responseData := GetCommentsData{
+		Total:    total,
+		Comments: commentsToReturn,
+	}
+	sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "success", Data: responseData})
+}
+*/
+
+func getCommentsHandler(database *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodOptions {
+			sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "OPTIONS OK"})
+			return
+		}
+		if r.Method != http.MethodGet {
+			sendJSONResponse(w, http.StatusMethodNotAllowed, UnifiedResponse{Code: 1, Msg: "invalid method"})
+			return
+		}
+
+		pageStr := r.URL.Query().Get("page")
+		sizeStr := r.URL.Query().Get("size")
+
+		page, err := strconv.Atoi(pageStr)
+		if err != nil || page < 1 {
+			page = 1
+		}
+
+		size, err := strconv.Atoi(sizeStr)
+		if err != nil || size == 0 {
+			size = 10 // 默认每页10条
+		}
+
+		var total int
+		// 查询总评论数
+		row := database.QueryRow("SELECT COUNT(*) FROM comments;")
+		err = row.Scan(&total)
+		if err != nil {
+			log.Printf("Error getting total comment count: %v", err)
+			sendJSONResponse(w, http.StatusInternalServerError, UnifiedResponse{Code: 1, Msg: "failed to get total count"})
+			return
+		}
+
+		var commentsToReturn []Comment
+		var selectSQL string
+		var args []interface{}
+
+		if size == -1 { // 显示全部
+			selectSQL = "SELECT id, name, content, created_at FROM comments ORDER BY created_at ASC;"
+			// args 保持为空
+		} else { // 分页
+			offset := (page - 1) * size
+			// 检查 offset 是否越界，虽然数据库会处理，但这里可以提前打印警告或调整
+			if offset < 0 {
+				offset = 0
+			}
+			// 使用 ? 作为占位符，LIMIT 和 OFFSET 控制分页
+			selectSQL = "SELECT id, name, content, created_at FROM comments ORDER BY created_at ASC LIMIT ? OFFSET ?;"
+			args = []interface{}{size, offset}
+		}
+
+		// 执行查询
+		rows, err := database.Query(selectSQL, args...)
+		if err != nil {
+			log.Printf("Error querying comments: %v", err)
+			sendJSONResponse(w, http.StatusInternalServerError, UnifiedResponse{Code: 1, Msg: "failed to retrieve comments"})
+			return
+		}
+		defer rows.Close() // 确保关闭 rows
+
+		// 遍历结果集
+		for rows.Next() {
+			var c Comment
+			// 使用 Scan 将当前行的数据读入 Comment 结构体字段
+			err := rows.Scan(&c.ID, &c.Name, &c.Content, &c.CreatedAt)
+			if err != nil {
+				log.Printf("Error scanning comment row: %v", err)
+				// 扫描错误通常表示数据有问题或查询/结构体不匹配
+				continue // 跳过这一条，尝试下一条
+			}
+			commentsToReturn = append(commentsToReturn, c)
+		}
+
+		// 检查在遍历过程中是否发生了错误
+		if err = rows.Err(); err != nil {
+			log.Printf("Error during comments iteration: %v", err)
+			sendJSONResponse(w, http.StatusInternalServerError, UnifiedResponse{Code: 1, Msg: "error reading comments result"})
+			return
+		}
+
+		responseData := GetCommentsData{
+			Total:    total,
+			Comments: commentsToReturn,
+		}
+		sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "success", Data: responseData})
+	}
+}
+
+/*
+	func addCommentHandler(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodOptions {
+			sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "OPTIONS OK"})
+			return
+		}
+		if r.Method != http.MethodPost {
+			sendJSONResponse(w, http.StatusMethodNotAllowed, UnifiedResponse{Code: 1, Msg: "disapproval method"})
+			return
+		}
+
+		var reqBody AddCommentRequest
+		err := json.NewDecoder(r.Body).Decode(&reqBody)
+		if err != nil {
+			sendJSONResponse(w, http.StatusBadRequest, UnifiedResponse{Code: 1, Msg: "invalid request: " + err.Error()})
+			return
+		}
+		defer r.Body.Close()
+
+		if reqBody.Name == "" || reqBody.Content == "" {
+			sendJSONResponse(w, http.StatusBadRequest, UnifiedResponse{Code: 1, Msg: "name and content can't be empty"})
+			return
+		}
+
+		mutex.Lock()
+		defer mutex.Unlock()
+
+		newComment := Comment{
+			ID:      nextCommentID,
+			Name:    reqBody.Name,
+			Content: reqBody.Content,
+		}
+		comments = append(comments, newComment)
+		nextCommentID++
+
+		log.Printf("add comment: ID=%d, Name=%s", newComment.ID, newComment.Name)
+		sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "success", Data: newComment})
+	}
+*/
+func addCommentHandler(database *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodOptions {
+			sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "OPTIONS OK"})
+			return
+		}
+		if r.Method != http.MethodPost {
+			sendJSONResponse(w, http.StatusMethodNotAllowed, UnifiedResponse{Code: 1, Msg: "disapproval method"})
+			return
+		}
+
+		var reqBody AddCommentRequest
+		// 限制读取大小，防止滥用
+		// r.Body = http.MaxBytesReader(w, r.Body, 1048576) // 例如限制1MB
+		err := json.NewDecoder(r.Body).Decode(&reqBody)
+		if err != nil {
+			// 检查是否是读取大小限制错误
+			// if _, ok := err.(*http.MaxBytesError); ok {
+			// 	sendJSONResponse(w, http.StatusBadRequest, UnifiedResponse{Code: 1, Msg: "Request body too large"})
+			// 	return
+			// }
+			log.Printf("Error decoding request body: %v", err)
+			sendJSONResponse(w, http.StatusBadRequest, UnifiedResponse{Code: 1, Msg: "invalid request format"})
+			return
+		}
+		defer r.Body.Close() // 确保关闭请求体
+
+		if reqBody.Name == "" || reqBody.Content == "" {
+			sendJSONResponse(w, http.StatusBadRequest, UnifiedResponse{Code: 1, Msg: "name and content can't be empty"})
+			return
+		}
+
+		// 插入数据到数据库
+		insertSQL := "INSERT INTO comments (name, content) VALUES (?, ?);"
+		// Exec 用于执行 INSERT, UPDATE, DELETE 等不返回行的语句
+		result, err := database.Exec(insertSQL, reqBody.Name, reqBody.Content)
+		if err != nil {
+			log.Printf("Error inserting comment: %v", err)
+			sendJSONResponse(w, http.StatusInternalServerError, UnifiedResponse{Code: 1, Msg: "failed to save comment"})
+			return
+		}
+
+		// 获取新插入记录的ID
+		id, err := result.LastInsertId()
+		if err != nil {
+			log.Printf("Error getting last insert ID: %v", err)
+			// 即使获取ID失败，评论可能已经成功插入
+			// 可以选择返回成功，或者根据业务决定是否算失败
+			sendJSONResponse(w, http.StatusInternalServerError, UnifiedResponse{Code: 1, Msg: "failed to get new comment ID"})
+			return
+		}
+
+		log.Printf("add comment: ID=%d, Name=%s", id, reqBody.Name)
+		// 返回新评论的ID (可选，取决于前端是否需要立即知道)
+		// 可以通过查询刚刚插入的数据获取完整的 Comment 结构体，包括 created_at
+		// 或者只返回ID
+		sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "success", Data: map[string]int{"id": int(id)}})
+	}
+}
+
+/*
+func deleteCommentHandler(w http.ResponseWriter, r *http.Request) {
+	if r.Method == http.MethodOptions {
+		sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "options ok"})
+		return
+	}
+	if r.Method != http.MethodPost {
+		sendJSONResponse(w, http.StatusMethodNotAllowed, UnifiedResponse{Code: 1, Msg: "invalid method"})
+		return
+	}
+
+	idStr := r.URL.Query().Get("id")
+	commentID, err := strconv.Atoi(idStr)
+	if err != nil {
+		sendJSONResponse(w, http.StatusBadRequest, UnifiedResponse{Code: 1, Msg: "invalid comment ID"})
+		return
+	}
+
+	mutex.Lock()
+	defer mutex.Unlock()
+
+	found := false
+	newCommentsList := make([]Comment, 0, len(comments))
+	for _, c := range comments {
+		if c.ID == commentID {
+			found = true
+		} else {
+			newCommentsList = append(newCommentsList, c)
+		}
+	}
+
+	if !found {
+		sendJSONResponse(w, http.StatusNotFound, UnifiedResponse{Code: 1, Msg: "评论未找到"})
+		return
+	}
+
+	comments = newCommentsList
+	log.Printf("删除评论 ID: %d", commentID)
+	sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "success", Data: nil}) // [cite: 40]
+}
+*/
+
+func deleteCommentHandler(database *sql.DB) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if r.Method == http.MethodOptions {
+			sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "options ok"})
+			return
+		}
+		// 前端使用POST方法删除，所以这里保持POST
+		if r.Method != http.MethodPost {
+			sendJSONResponse(w, http.StatusMethodNotAllowed, UnifiedResponse{Code: 1, Msg: "invalid method"})
+			return
+		}
+
+		idStr := r.URL.Query().Get("id")
+		commentID, err := strconv.Atoi(idStr)
+		if err != nil {
+			sendJSONResponse(w, http.StatusBadRequest, UnifiedResponse{Code: 1, Msg: "invalid comment ID format"})
+			return
+		}
+
+		// 执行删除操作
+		deleteSQL := "DELETE FROM comments WHERE id = ?;"
+		result, err := database.Exec(deleteSQL, commentID)
+		if err != nil {
+			log.Printf("Error deleting comment ID %d: %v", commentID, err)
+			sendJSONResponse(w, http.StatusInternalServerError, UnifiedResponse{Code: 1, Msg: "failed to delete comment"})
+			return
+		}
+
+		// 检查影响的行数，判断是否删除了记录
+		rowsAffected, err := result.RowsAffected()
+		if err != nil {
+			log.Printf("Error getting rows affected for delete ID %d: %v", commentID, err)
+			// 即使获取行数失败，删除操作可能已经成功，或者本来就没找到，这里可以返回成功或根据业务决定
+			sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "delete operation attempted, status unknown"})
+			return
+		}
+
+		if rowsAffected == 0 {
+			// 没有找到匹配ID的评论
+			log.Printf("Delete comment ID %d not found", commentID)
+			sendJSONResponse(w, http.StatusNotFound, UnifiedResponse{Code: 1, Msg: "评论未找到"})
+			return
+		}
+
+		log.Printf("删除评论 ID: %d", commentID)
+		sendJSONResponse(w, http.StatusOK, UnifiedResponse{Code: 0, Msg: "success", Data: nil})
+	}
+}
+
+/*
+func loggingMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+
+		lrw := &loggingResponseWriter{ResponseWriter: w, statusCode: http.StatusOK}
+
+		next.ServeHTTP(lrw, r)
+
+		log.Printf(
+			"request: %s %s, answer: %d, time_comsume: %s",
+			r.Method,
+			r.RequestURI,
+			lrw.statusCode,
+			time.Since(start),
+		)
+	})
+}
+*/
+
+func loggingMiddleware(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		start := time.Now()
+		lrw := &loggingResponseWriter{ResponseWriter: w, statusCode: http.StatusOK}
+		next.ServeHTTP(lrw, r)
+		log.Printf(
+			"request: %s %s, answer: %d, time_comsume: %s",
+			r.Method,
+			r.RequestURI,
+			lrw.statusCode,
+			time.Since(start),
+		)
+	})
+}
+
+type loggingResponseWriter struct {
+	http.ResponseWriter
+	statusCode int
+}
+
+func (lrw *loggingResponseWriter) WriteHeader(code int) {
+	lrw.statusCode = code
+	lrw.ResponseWriter.WriteHeader(code)
+}
+
+func timeoutMiddleware(next http.Handler, duration time.Duration) http.Handler {
+	return http.TimeoutHandler(next, duration, "time exceed")
+}
+
+/*
+func loadInitialData() {
+	mutex.Lock()
+	defer mutex.Unlock()
+	if len(comments) == 0 {
+		comments = append(comments, Comment{ID: nextCommentID, Name: "thy", Content: "这是第一条评论qaq"})
+		nextCommentID++
+		comments = append(comments, Comment{ID: nextCommentID, Name: "thy", Content: "这是第一条评论qwq"})
+		nextCommentID++
+		comments = append(comments, Comment{ID: nextCommentID, Name: "thy", Content: "这是第一条评论awa"})
+		nextCommentID++
+		log.Println("initial comments loading successfully")
+	}
+}
+*/
+
+func loadInitialData(database *sql.DB) {
+	// 检查数据库是否已经有评论
+	var count int
+	row := database.QueryRow("SELECT COUNT(*) FROM comments;")
+	err := row.Scan(&count)
+	if err != nil {
+		log.Printf("Error checking initial data count: %v", err)
+		return
+	}
+	if count == 0 {
+		log.Println("No comments found, inserting initial data.")
+		// 使用事务插入多条数据
+		tx, err := database.Begin()
+		if err != nil {
+			log.Printf("Error starting transaction for initial data: %v", err)
+			return
+		}
+		defer tx.Rollback() // 如果后续操作失败，回滚事务
+
+		insertSQL := "INSERT INTO comments (name, content) VALUES (?, ?);"
+		stmt, err := tx.Prepare(insertSQL)
+		if err != nil {
+			log.Printf("Error preparing statement for initial data: %v", err)
+			return
+		}
+		defer stmt.Close()
+
+		initialComments := []struct{ Name, Content string }{
+			{"thyA", "这是第一条初始化评论！"},
+			{"thyB", "这是第二条初始化评论！"},
+			{"thyC", "这是第三条初始化评论！"},
+		}
+
+		for _, c := range initialComments {
+			_, err := stmt.Exec(c.Name, c.Content)
+			if err != nil {
+				log.Printf("Error inserting initial comment (%s): %v", c.Name, err)
+				return // 插入失败，回滚整个事务
+			}
+		}
+
+		err = tx.Commit() // 提交事务
+		if err != nil {
+			log.Printf("Error committing transaction for initial data: %v", err)
+			return
+		}
+		log.Println("Initial comments loaded successfully into database.")
+	} else {
+		log.Printf("Database already contains %d comments, skipping initial data load.", count)
+	}
+}
+
+func main() {
+
+	var err error
+	db, err = initDB("comments.db")
+	if err != nil {
+		log.Fatalf("Failed to initialize database: %v", err)
+	}
+	defer db.Close()
+
+	loadInitialData(db)
+
+	mux := http.NewServeMux()
+	/*
+		mux.HandleFunc("/comment/get", getCommentsHandler)
+		mux.HandleFunc("/comment/add", addCommentHandler)
+		mux.HandleFunc("/comment/delete", deleteCommentHandler)
+	*/
+
+	mux.HandleFunc("/comment/get", getCommentsHandler(db))
+	mux.HandleFunc("/comment/add", addCommentHandler(db))
+	mux.HandleFunc("/comment/delete", deleteCommentHandler(db))
+
+	loggedMux := loggingMiddleware(mux)
+
+	port := ":8080"
+	log.Printf("server is current working on %s\n", port)
+
+	if err := http.ListenAndServe(port, loggedMux); err != nil {
+		log.Fatalf("can't start server: %s\n", err.Error())
+	}
+}