我对服务器端非常陌生。我刚刚开始使用 Node.js 和 mongodb。
示例代码:
var http = require('http');
var mongoose = require('mongoose');
http.createServer(function (req, res) {
res.writeHead(200, {'Content-Type': 'application/json; charset=utf-8'});
mongoose.connect('mongodb://localhost/bookmarks');
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function callback () {
// console.log('Running');
var Users = mongoose.model('users', { name: String, lastname: String, yas: Number, yer:String });
Users.find().lean().exec(function(err,users) {
// console.log(JSON.stringify(users));
var sonuc=JSON.stringify(users);
console.log(sonuc);
res.end(sonuc);
});
});
}).listen(1337,'127.0.0.1');
运行我的代码时,它第一次工作,但是当我尝试刷新页面时,出现此错误并且没有响应:
connection error: { [Error: Trying to open unclosed connection.] state: 1 }
最佳答案
您将针对每个请求打开一个新的数据库连接。您可以通过以下一种方法重新排列代码以创建一个连接和一个 Users
对象,并稍后在请求处理程序中使用它:
var http = require('http');
var mongoose = require('mongoose');
// we want Users to be in the global scope here, not in a function
// that way different functions can both see the same variable
var Users = null;
mongoose.connect('mongodb://localhost/bookmarks');
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
// By placing Users and createServer inside the db.once('open') callback,
// we wait till mongo is ready before letting the http handler query users:
db.once('open', function(){
console.log('Running');
// now overwrite the already defined Users variable:
Users = mongoose.model('users', { name: String, lastname: String, yas: Number, yer:String });
http.createServer(function (req, res) {
findUsers(function(err, results){
if(err){
res.writeHead(500);
res.end();
} else {
res.writeHead(200, {'Content-Type': 'application/json; charset=utf-8'});
res.end(results);
};
});
}).listen(1337,127.0.0.1);
});
function findUsers(callback){
Users.find().lean().exec(function(err,users) {
// console.log(JSON.stringify(users));
var sonuc=JSON.stringify(users);
console.log(sonuc);
//res.end(sonuc);
callback(err, sonuc);
});
}
关于node.js - Mongodb 和 Node.js 连接错误,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/23565420/