我正在尝试网站http://code.runnable.com/U108R8ihwn4m4TM5/user-creation-signup-and-login-with-express-4-and-mongodb-for-node-js中的代码以及运行
时的代码node server.js
出现以下错误
module.js:340
throw err;
^
Error: Cannot find module 'connect-mongo'
at Function.Module._resolveFilename (module.js:338:15)
at Function.Module._load (module.js:280:25)
at Module.require (module.js:364:17)
at require (module.js:380:17)
at Object.<anonymous> (/home/amitnaik01/Login/server.js:6:18)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
at Module.load (module.js:356:32)
at Function.Module._load (module.js:312:12)
at Function.Module.runMain (module.js:497:10)
package.json文件如下：
{
"name": "ExpressApp",
"version": "0.0.1",
"description": "A Node.js App using express",
"dependencies": {
"express": "~4.0.0",
"body-parser": "~1.0.2",
"express-session": "~1.0.3",
"express3-handlebars": "~0.5.0",
"mongodb": "~1.4.2",
"connect-mongo": "git+https://github.com/kcbanner/connect-mongo.git#master",
"cookie-parser": "~1.0.1"
},
"engine": "node >=0.6.x"
}
server.js文件位于
之下var express = require('express');
var app = express();
var expressSession = require('express-session');
var expressHbs = require('express3-handlebars');
var mongoUrl = 'mongodb://localhost:27017/dbname';
var MongoStore = require('connect-mongo')(expressSession);
var mongo = require('./mongo');
var port = 8000; // for heroku you would use process.env.PORT instead
// This is a middleware that we will use on routes where
// we _require_ that a user is logged in, such as the /secret url
function requireUser(req, res, next){
if (!req.user) {
res.redirect('/not_allowed');
} else {
next();
}
}
// This middleware checks if the user is logged in and sets
// req.user and res.locals.user appropriately if so.
function checkIfLoggedIn(req, res, next){
if (req.session.username) {
var coll = mongo.collection('users');
coll.findOne({username: req.session.username}, function(err, user){
if (user) {
// set a 'user' property on req
// so that the 'requireUser' middleware can check if the user is
// logged in
req.user = user;
// Set a res.locals variable called 'user' so that it is available
// to every handlebars template.
res.locals.user = user;
}
next();
});
} else {
next();
}
}
// Use this so we can get access to `req.body` in our posted login
// and signup forms.
app.use( require('body-parser')() );
// We need to use cookies for sessions, so use the cookie parser middleware
app.use( require('cookie-parser')() );
app.use( expressSession({
secret: 'somesecretrandomstring',
store: new MongoStore({
url: mongoUrl
})
}));
// We must use this middleware _after_ the expressSession middleware,
// because checkIfLoggedIn checks the `req.session.username` value,
// which will not be available until after the session middleware runs.
app.use(checkIfLoggedIn);
app.engine('hbs', expressHbs({extname:'hbs', defaultLayout:'main.hbs'}));
app.set('view engine', 'hbs');
app.get('/', function(req, res){
var coll = mongo.collection('users');
coll.find({}).toArray(function(err, users){
res.render('index', {users:users});
})
});
app.get('/login', function(req, res){
res.render('login');
});
app.get('/logout', function(req, res){
delete req.session.username;
res.redirect('/');
});
app.get('/not_allowed', function(req, res){
res.render('not_allowed');
});
// The /secret url includes the requireUser middleware.
app.get('/secret', requireUser, function(req, res){
res.render('secret');
});
app.get('/signup', function(req,res){
res.render('signup');
});
// This creates a new user and calls the callback with
// two arguments: err, if there was an error, and the created user
// if a new user was created.
//
// Possible errors: the passwords are not the same, and a user
// with that username already exists.
function createUser(username, password, password_confirmation, callback){
var coll = mongo.collection('users');
if (password !== password_confirmation) {
var err = 'The passwords do not match';
callback(err);
} else {
var query = {username:username};
var userObject = {username: username, password: password};
// make sure this username does not exist already
coll.findOne(query, function(err, user){
if (user) {
err = 'The username you entered already exists';
callback(err);
} else {
// create the new user
coll.insert(userObject, function(err,user){
callback(err,user);
});
}
});
}
}
app.post('/signup', function(req, res){
// The 3 variables below all come from the form
// in views/signup.hbs
var username = req.body.username;
var password = req.body.password;
var password_confirmation = req.body.password_confirmation;
createUser(username, password, password_confirmation, function(err, user){
if (err) {
res.render('signup', {error: err});
} else {
// This way subsequent requests will know the user is logged in.
req.session.username = user.username;
res.redirect('/');
}
});
});
// This finds a user matching the username and password that
// were given.
function authenticateUser(username, password, callback){
var coll = mongo.collection('users');
coll.findOne({username: username, password:password}, function(err, user){
callback(err, user);
});
}
app.post('/login', function(req, res){
// These two variables come from the form on
// the views/login.hbs page
var username = req.body.username;
var password = req.body.password;
authenticateUser(username, password, function(err, user){
if (user) {
// This way subsequent requests will know the user is logged in.
req.session.username = user.username;
res.redirect('/');
} else {
res.render('login', {badCredentials: true});
}
});
});
app.use('/public', express.static('public'));
mongo.connect(mongoUrl, function(){
console.log('Connected to mongo at: ' + mongoUrl);
app.listen(port, function(){
console.log('Server is listening on port: '+port);
});
})
无论如何都要解决这个错误？
答案 0 :(得分：1)
看起来，节点模块中缺少connect-mongo。请安装并保存（将其保存在package.json中只是一种很好的做法）。
npm install connect-mongo --save
或者简单地说，
npm i --s connect-mongo
<强>更新
Syntax error因旧节点版本而异，请输入以下命令来更新Nodejs。
sudo npm cache clean -f
sudo npm install -g n
sudo n stable
答案 1 :(得分：0)
再次安装此模块。
npm install connect-mongo
将其版本更改为最新版本。