mysql - 在哪里放置代码以显示从 MySQL 到 Handlebars 的数据?
问题描述
目标:
我的目标是自学如何使用 Node JS、MySQL 和 express。
我正在努力理解将 MySQL 数据加载到 HTML 中的代码的放置位置。
让我向您展示整个代码。
应用程序.js
var express = require('express');
var mysql = require('mysql');
var dotenv = require('dotenv');
var path = require('path');
var cookieParser = require('cookie-parser');
dotenv.config({path: './.env'});
var app = express();
// Connection to MySQL
var db = mysql.createConnection({
host: process.env.DATABASE_HOST,
user: process.env.DATABASE_USER,
password: process.env.DATABASE_PASSWORD,
database: process.env.DATABASE
});
db.connect(function(error) {
if(error) {
console.log(error);
}
else{
console.log("Connected");
}
});
// Parse URL-Encoded bodies
app.use(express.urlencoded({extended: false}));
// Parse JSON bodies
app.use(express.json());
// Initialize a cookie
app.use(cookieParser());
// View engine to control HTML
app.set('view engine', 'hbs');
// Public dir
var publicDir = path.join(__dirname, './public');
app.use(express.static(publicDir));
// Define routes
app.use('/', require('./routes/pages'));
app.use('/auth', require('./routes/auth'));
app.listen(3000, function() {
console.log("Server is running on port 3000");
});
路线/pages.js
var express = require('express');
var authController = require('../controllers/auth');
var router = express.Router();
// Home
router.get("/", authController.isLoggedIn, function(req,res) {
res.render("index", {
user: req.user
});
});
// Register
router.get("/register", function(req, res) {
res.render("register");
});
// Login
router.get("/login", function(req, res) {
res.render("login");
});
// Profile
router.get('/profile', authController.isLoggedIn, function(req, res) {
if(req.user) {
res.render('profile', {
user: req.user
});
}
else {
res.redirect('login');
}
});
// Forum
router.get('/forums', authController.isLoggedIn, function(req, res) {
if(req.user) {
res.render('forums');
} else {
res.redirect('login');
}
});
// English Division //
// Premier League
router.get('/Leagues/EnglishDivision', authController.isLoggedIn, function(req, res) {
if(req.user) {
res.render('PremierLeague');
} else {
res.redirect('../../login');
}
});
module.exports = router;
路线/auth.js
var express = require('express');
var authController = require('../controllers/auth');
var router = express.Router();
// Register
router.post("/register", authController.register);
// Login
router.post("/login", authController.login);
// Logout
router.get('/logout', authController.logout);
module.exports = router;
控制器/auth.js
var mysql = require('mysql');
var jwt = require('jsonwebtoken');
var bcrypt = require('bcryptjs');
var {promisify} = require('util');
// Connection to MySQL
var db = mysql.createConnection({
host: process.env.DATABASE_HOST,
user: process.env.DATABASE_USER,
password: process.env.DATABASE_PASSWORD,
database: process.env.DATABASE
});
// Register function
exports.register = function(req, res) {
console.log(req.body);
var {name, email, password, passwordConfirm} = req.body;
db.query("SELECT email FROM users WHERE email = ?", [email], function(error, result) {
if(error){
console.log(error);
}
if(result.length > 0) {
return res.render('register', {
message: 'That email is already in use'
})
} else if(password !== passwordConfirm) {
return res.render('register', {
message: 'Passwords do not match'
});
}
let hashedPassword = bcrypt.hashSync(password, 8);
console.log(hashedPassword);
// Insert user details into MySQL
db.query('INSERT INTO users set ?', {name: name, email: email, password: hashedPassword, dateJoined: new Date()}, function(error, result) {
if(error) {
console.log(error);
} else {
console.log(result);
return res.render('register', {
message: 'User registered'
});
}
});
});
}
// Login function
exports.login = function(req, res) {
try {
var {email, password} = req.body;
if(!email || !password) {
return res.status(400).render('login', {
message: 'Please provide an email and password'
});
}
db.query('SELECT * FROM users WHERE email = ?', [email], async function(error, result) {
console.log(result);
if(!result.length > 0 || !(await bcrypt.compare(password, result[0].password))) {
res.status(401).render('login', {
message: 'The email or password is incorrect'
});
}
else {
var id = result[0].id;
// Create a token
var token = jwt.sign({id}, process.env.JWT_SECRET, {
expiresIn: process.env.JWT_EXPIRES_IN
});
console.log("The token is " + token);
// Create a cookie
var cookieOptions = {
expires: new Date(
Date.now() + process.env.JWT_COOKIE_EXPIRES * 24 * 60 * 60 * 1000
),
httpOnly: true
}
// Set up a cookie
res.cookie('jwt', token, cookieOptions);
res.status(200).redirect("/");
}
});
} catch (error) {
console.log(error);
}
}
// Check if logged in
exports.isLoggedIn = async function(req, res, next) {
console.log(req.cookies);
if(req.cookies.jwt){
try {
// Verify the token
var decoded = await promisify(jwt.verify)(req.cookies.jwt, process.env.JWT_SECRET);
console.log(decoded);
// Check if user exist
db.query("SELECT id, name, email, password, date_format(datejoined, '%d/%m/%Y') as dateJoined FROM users WHERE id = ?", [decoded.id], function(error, result) {
console.log(result);
// If no result
if(!result) {
return next();
}
req.user = result[0];
return next();
});
}
catch (e) {
console.log(e);
return next();
}
} else{
next();
}
}
// Logout function
exports.logout = async function(req, res) {
res.clearCookie('jwt');
res.status(200).redirect('/');
}
问题
在我的.hbs
文件中,PremierLeague
我想以 HTML 格式加载 MySQL 数据。我需要在下面的代码中从哪里开始?
期望的目标:
这是用户点击查看英超联赛的时间
MySQL 中的 Foreach 记录我想为每条记录添加一张新卡。我知道如何使用 HandleBars {{some.data}}
。
- 我只是不知道我在哪里编码查询?
- 它需要在控制器中还是可以在控制器中
router.get(...
? - 另外我该如何
{{#foreach}}
正确使用?
解决方案
您不需要任何其他特定的控制器,编码查询的正确位置实际上是路由本身。
但在进入问题的核心之前,让我们先谈谈您的代码。
我可以看到您不止一次执行与数据库的连接,您可以添加数据库专用控制器,例如:
控制器/db.js
var mysql = require('mysql');
var dotenv = require('dotenv');
dotenv.config({path: './.env'});
// Connection to MySQL
var db = mysql.createConnection({
host: process.env.DATABASE_HOST,
user: process.env.DATABASE_USER,
password: process.env.DATABASE_PASSWORD,
database: process.env.DATABASE
});
function connect(done) {
db.connect(done);
}
module.exports = { db: db, connect: connect };
这使您只需一行即可从每个文件访问数据库实例:
var db = require('./controllers/db').db;
比您可以connect
在您的应用程序中使用该功能:
应用程序.js
var express = require('express');
var db = require(./controllers/db);
var path = require('path');
var cookieParser = require('cookie-parser');
// set up your server
var app = express();
// Parse URL-Encoded bodies
app.use(express.urlencoded({extended: false}));
// Parse JSON bodies
app.use(express.json());
// Initialize a cookie
app.use(cookieParser());
// View engine to control HTML
app.set('view engine', 'hbs');
// Public dir
var publicDir = path.join(__dirname, './public');
app.use(express.static(publicDir));
// Define routes
app.use('/', require('./routes/pages'));
app.use('/auth', require('./routes/auth'));
// finally run your server only if you can connect to the database
db.connect(function(error) {
if(error) return console.log("Error connecting to the database:", error);
app.listen(3000, function() {
console.log("Server is running on port 3000");
});
});
您还可以简化您的控制器/auth.js删除数据库连接的东西并仅使用该行来要求您的数据库控制器。
最后,您可以对查询进行编码:
路线/pages.js
var express = require('express');
var authController = require('../controllers/auth');
var db = require('../controllers/db').db;
var router = express.Router();
// Omissis... other routes
// Premier League
router.get('/Leagues/EnglishDivision', authController.isLoggedIn, function(req, res) {
// a good practice is first to handle possible exit cases to reduce nesting levels
if(! req.user) return res.redirect('../../login');
// this is actually the right place to perform queries
db.query('SELECT ...', [...], function(error, results) {
// once again first possible exit cases
if(error) return res.status(500).end(error.message)
res.render('PremierLeague', { results: results });
});
});
module.exports = router;
最后在PremierLeague.hbs文件中,您可以处理results
in#foreach
指令。
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