Express 加 sqlite3 写一个简单博客

例图：

搭建命令：

前提已装好node.js

开始创建项目结构

npm init -y
package.json:{"name": "ex01","version": "1.0.0","main": "index.js","scripts": {"test": "echo \"Error: no test specified\" && exit 1"},"keywords": [],"author": "","license": "ISC","description": ""
}
安装必要的依赖

npm install express sqlite3 ejs express-session body-parser

代码：

app.js

const express = require('express');
const session = require('express-session');
const bodyParser = require('body-parser');
const path = require('path');
const db = require('./database');const app = express();// 配置中间件
app.set('view engine', 'ejs');
app.use(express.static(path.join(__dirname, 'public')));
app.use(bodyParser.urlencoded({ extended: false }));
app.use(session({secret: 'blog_secret_key',resave: false,saveUninitialized: true
}));// 首页路由
app.get('/', async (req, res) => {try {const category_id = req.query.category;const search = req.query.search;let posts;let categories = await db.all('SELECT * FROM categories');if (search) {// 搜索标题和内容posts = await db.all(`SELECT posts.*, categories.name as category_name FROM posts LEFT JOIN categories ON posts.category_id = categories.id WHERE title LIKE ? OR content LIKE ?ORDER BY created_at DESC`, [`%${search}%`, `%${search}%`]);} else if (category_id) {posts = await db.all(`SELECT posts.*, categories.name as category_name FROM posts LEFT JOIN categories ON posts.category_id = categories.id WHERE category_id = ? ORDER BY created_at DESC`, [category_id]);} else {posts = await db.all(`SELECT posts.*, categories.name as category_name FROM posts LEFT JOIN categories ON posts.category_id = categories.id ORDER BY created_at DESC`);}res.render('index', { posts, categories, current_category: category_id,search_query: search || ''});} catch (err) {res.status(500).send('数据库错误');}
});// 创建博文页面
app.get('/post/new', async (req, res) => {try {const categories = await db.all('SELECT * FROM categories');res.render('new', { categories });} catch (err) {res.status(500).send('获取分类失败');}
});// 提交新博文
app.post('/post/new', async (req, res) => {const { title, content, category_id } = req.body;try {await db.run('INSERT INTO posts (title, content, category_id, created_at) VALUES (?, ?, ?, ?)',[title, content, category_id, new Date().toISOString()]);res.redirect('/');} catch (err) {res.status(500).send('创建博文失败');}
});// 查看单篇博文
app.get('/post/:id', async (req, res) => {try {const post = await db.get(`SELECT posts.*, categories.name as category_name FROM posts LEFT JOIN categories ON posts.category_id = categories.id WHERE posts.id = ?`, [req.params.id]);if (post) {res.render('post', { post });} else {res.status(404).send('博文不存在');}} catch (err) {res.status(500).send('数据库错误');}
});// 编辑博文页面
app.get('/post/:id/edit', async (req, res) => {try {const post = await db.get('SELECT * FROM posts WHERE id = ?', [req.params.id]);const categories = await db.all('SELECT * FROM categories');if (post) {res.render('edit', { post, categories });} else {res.status(404).send('博文不存在');}} catch (err) {res.status(500).send('数据库错误');}
});// 更新博文
app.post('/post/:id/edit', async (req, res) => {const { title, content, category_id } = req.body;try {await db.run('UPDATE posts SET title = ?, content = ?, category_id = ? WHERE id = ?',[title, content, category_id, req.params.id]);res.redirect(`/post/${req.params.id}`);} catch (err) {res.status(500).send('更新博文失败');}
});// 删除博文
app.post('/post/:id/delete', async (req, res) => {try {await db.run('DELETE FROM posts WHERE id = ?', [req.params.id]);res.redirect('/');} catch (err) {res.status(500).send('删除博文失败');}
});const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {console.log(`服务器运行在 http://localhost:${PORT}`);
});

database.js

const sqlite3 = require('sqlite3').verbose();
const path = require('path');// 创建数据库连接
const db = new sqlite3.Database(path.join(__dirname, 'blog.db'), (err) => {if (err) {console.error('数据库连接失败:', err);} else {console.log('成功连接到数据库');initDatabase().catch(err => {console.error('数据库初始化失败:', err);});}
});// 初始化数据库表
async function initDatabase() {try {// 检查表是否存在const tablesExist = await get(`SELECT name FROM sqlite_master WHERE type='table' AND (name='posts' OR name='categories')`);if (!tablesExist) {console.log('首次运行，创建数据库表...');// 创建分类表await run(`CREATE TABLE IF NOT EXISTS categories (id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT NOT NULL UNIQUE)`);console.log('分类表创建成功');// 创建文章表await run(`CREATE TABLE IF NOT EXISTS posts (id INTEGER PRIMARY KEY AUTOINCREMENT,title TEXT NOT NULL,content TEXT NOT NULL,category_id INTEGER,created_at DATETIME DEFAULT CURRENT_TIMESTAMP,FOREIGN KEY (category_id) REFERENCES categories(id))`);console.log('文章表创建成功');// 插入默认分类await run(`INSERT INTO categories (name) VALUES ('技术'),('生活'),('随笔')`);console.log('默认分类创建成功');} else {console.log('数据库表已存在，跳过初始化');}} catch (err) {console.error('数据库初始化错误:', err);throw err;}
}// Promise 包装数据库操作
function run(sql, params = []) {return new Promise((resolve, reject) => {db.run(sql, params, function(err) {if (err) {console.error('SQL执行错误:', err);reject(err);} else {resolve(this);}});});
}function get(sql, params = []) {return new Promise((resolve, reject) => {db.get(sql, params, (err, result) => {if (err) {console.error('SQL执行错误:', err);reject(err);} else {resolve(result);}});});
}function all(sql, params = []) {return new Promise((resolve, reject) => {db.all(sql, params, (err, rows) => {if (err) {console.error('SQL执行错误:', err);reject(err);} else {resolve(rows);}});});
}// 关闭数据库连接
process.on('SIGINT', () => {db.close((err) => {if (err) {console.error('关闭数据库时出错:', err);} else {console.log('数据库连接已关闭');}process.exit(0);});
});module.exports = {run,get,all
};

views\index.ejs

<!DOCTYPE html>
<html>
<head><title>我的博客</title><meta charset="UTF-8"><style>body { font-family: Arial, sans-serif;max-width: 800px;margin: 0 auto;padding: 20px;}.post {margin-bottom: 20px;padding: 15px;border: 1px solid #ddd;border-radius: 5px;}.post h2 {margin-top: 0;}.post-date {color: #666;font-size: 0.9em;}.new-post-btn {display: inline-block;padding: 10px 20px;background-color: #007bff;color: white;text-decoration: none;border-radius: 5px;margin-bottom: 20px;}.categories {margin: 20px 0;padding: 10px 0;border-bottom: 1px solid #eee;}.category-link {display: inline-block;padding: 5px 10px;margin-right: 10px;text-decoration: none;color: #666;border-radius: 3px;}.category-link.active {background-color: #007bff;color: white;}.post-category {display: inline-block;padding: 3px 8px;background-color: #e9ecef;border-radius: 3px;font-size: 0.9em;margin-right: 10px;}.search-box {margin: 20px 0;display: flex;gap: 10px;}.search-input {flex: 1;padding: 8px;border: 1px solid #ddd;border-radius: 4px;font-size: 1em;}.search-btn {padding: 8px 20px;background-color: #007bff;color: white;border: none;border-radius: 4px;cursor: pointer;}.search-btn:hover {background-color: #0056b3;}.search-results {margin-bottom: 20px;padding: 10px;background-color: #f8f9fa;border-radius: 4px;}.search-results-hidden {display: none;}</style>
</head>
<body><h1>博客文章列表</h1><a href="/post/new" class="new-post-btn">写新文章</a><form class="search-box" action="/" method="GET"><input type="text" name="search" class="search-input" placeholder="搜索文章标题或内容..." value="<%= search_query %>"><button type="submit" class="search-btn">搜索</button></form><div class="search-results <%= !search_query ? 'search-results-hidden' : '' %>">搜索结果: "<%= search_query || '' %>" - 找到 <%= posts ? posts.length : 0 %> 篇文章</div><div class="categories"><a href="/" class="category-link <%= !current_category ? 'active' : '' %>">全部</a><% categories.forEach(function(category) { %><a href="/?category=<%= category.id %>" class="category-link <%= current_category == category.id ? 'active' : '' %>"><%= category.name %></a><% }); %></div><% if (posts && posts.length > 0) { %><% posts.forEach(function(post) { %><div class="post"><h2><a href="/post/<%= post.id %>"><%= post.title %></a></h2><div class="post-meta"><span class="post-category"><%= post.category_name || '未分类' %></span><span class="post-date">发布时间: <%= new Date(post.created_at).toLocaleString() %></span></div><p><%= post.content.substring(0, 200) %>...</p></div><% }); %><% } else { %><p>还没有任何博客文章。</p><% } %>
</body>
</html>

views\post.ejs

<!DOCTYPE html>
<html>
<head><title><%= post.title %> - 我的博客</title><meta charset="UTF-8"><style>body {font-family: Arial, sans-serif;max-width: 800px;margin: 0 auto;padding: 20px;}.post-title {margin-bottom: 10px;}.post-meta {color: #666;margin-bottom: 20px;}.post-content {line-height: 1.6;white-space: pre-wrap;}.back-link {display: inline-block;margin-bottom: 20px;color: #007bff;text-decoration: none;}.post-category {display: inline-block;padding: 3px 8px;background-color: #e9ecef;border-radius: 3px;font-size: 0.9em;margin-right: 10px;}.action-buttons {margin: 20px 0;display: flex;gap: 10px;}.edit-btn {padding: 5px 15px;background-color: #28a745;color: white;text-decoration: none;border-radius: 3px;font-size: 0.9em;}.delete-btn {padding: 5px 15px;background-color: #dc3545;color: white;border: none;border-radius: 3px;cursor: pointer;font-size: 0.9em;}.delete-btn:hover {background-color: #c82333;}</style>
</head>
<body><a href="/" class="back-link">← 返回首页</a><article><h1 class="post-title"><%= post.title %></h1><div class="post-meta"><span class="post-category"><%= post.category_name || '未分类' %></span><span class="post-date">发布时间: <%= new Date(post.created_at).toLocaleString() %></span></div><div class="action-buttons"><a href="/post/<%= post.id %>/edit" class="edit-btn">编辑文章</a><form action="/post/<%= post.id %>/delete" method="POST" style="display: inline;" onsubmit="return confirm('确定要删除这篇文章吗？');"><button type="submit" class="delete-btn">删除文章</button></form></div><div class="post-content"><%= post.content %></div></article>
</body>
</html>

views\new.ejs

<!DOCTYPE html>
<html>
<head><title>写新文章 - 我的博客</title><meta charset="UTF-8"><style>body {font-family: Arial, sans-serif;max-width: 800px;margin: 0 auto;padding: 20px;}form {display: flex;flex-direction: column;}input, textarea, select {margin: 10px 0;padding: 8px;border: 1px solid #ddd;border-radius: 4px;}textarea {height: 300px;}button {padding: 10px 20px;background-color: #007bff;color: white;border: none;border-radius: 5px;cursor: pointer;}button:hover {background-color: #0056b3;}.back-link {display: inline-block;margin-bottom: 20px;color: #007bff;text-decoration: none;}label {margin-top: 10px;color: #666;}</style>
</head>
<body><a href="/" class="back-link">← 返回首页</a><h1>写新文章</h1><form action="/post/new" method="POST"><label for="title">文章标题</label><input type="text" id="title" name="title" placeholder="文章标题" required><label for="category">选择分类</label><select id="category" name="category_id" required><option value="">请选择分类</option><% categories.forEach(function(category) { %><option value="<%= category.id %>"><%= category.name %></option><% }); %></select><label for="content">文章内容</label><textarea id="content" name="content" placeholder="文章内容" required></textarea><button type="submit">发布文章</button></form>
</body>
</html>

views\edit.ejs

<!DOCTYPE html>
<html>
<head><title>编辑文章 - 我的博客</title><meta charset="UTF-8"><style>body {font-family: Arial, sans-serif;max-width: 800px;margin: 0 auto;padding: 20px;}form {display: flex;flex-direction: column;}input, textarea, select {margin: 10px 0;padding: 8px;border: 1px solid #ddd;border-radius: 4px;}textarea {height: 300px;}button {padding: 10px 20px;background-color: #007bff;color: white;border: none;border-radius: 5px;cursor: pointer;}button:hover {background-color: #0056b3;}.back-link {display: inline-block;margin-bottom: 20px;color: #007bff;text-decoration: none;}label {margin-top: 10px;color: #666;}</style>
</head>
<body><a href="/post/<%= post.id %>" class="back-link">← 返回文章</a><h1>编辑文章</h1><form action="/post/<%= post.id %>/edit" method="POST"><label for="title">文章标题</label><input type="text" id="title" name="title" value="<%= post.title %>" required><label for="category">选择分类</label><select id="category" name="category_id" required><option value="">请选择分类</option><% categories.forEach(function(category) { %><option value="<%= category.id %>" <%= post.category_id == category.id ? 'selected' : '' %>><%= category.name %></option><% }); %></select><label for="content">文章内容</label><textarea id="content" name="content" required><%= post.content %></textarea><button type="submit">更新文章</button></form>
</body>
</html>