我正尝试开始使用 mongoose 网站上的小猫示例,但我一直收到此错误消息:
process.nextTick(function() { throw err; }) ^ TypeError: undefined is not a function
我的代码是直接从网站上的例子复制过来的,但是不行。
var express = require('express');
var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/db');
var app = express();
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function (callback) {
var kittySchema = mongoose.Schema({
name: String
})
var Kitten = mongoose.model('Kitten', kittySchema)
var silence = new Kitten({ name: 'Silence' })
console.log(silence.name) // 'Silence'
// NOTE: methods must be added to the schema before compiling it with mongoose.model()
kittySchema.methods.speak = function () {
var greeting = this.name
? "Meow name is " + this.name
: "I don't have a name"
console.log(greeting);
}
var Kitten = mongoose.model('Kitten', kittySchema)
var fluffy = new Kitten({ name: 'fluffy' });
fluffy.speak() // "Meow name is fluffy"
});
app.get('/', function(req, res) {
res.send('hello world');
});
app.get('/secret', function(req, res) {
res.send('secret page');
});
var port = process.env.PORT || 1337;
app.listen(port, function() {
console.log('http://127.0.0.1:' + port + '/');
});
如果答案很明显,我很抱歉,但我刚刚开始使用 Node.js,需要一些帮助来掌握它。
提前谢谢你。
更新:完整的错误信息
/Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/lib/server.js:274
process.nextTick(function() { throw err; })
^
TypeError: undefined is not a function
at NativeConnection.<anonymous> (/Users/joseph/Documents/Atom-files/test/app.js:18:17)
at NativeConnection.g (events.js:199:16)
at NativeConnection.emit (events.js:104:17)
at open (/Users/joseph/Documents/Atom-files/node_modules/mongoose/lib/connection.js:485:10)
at NativeConnection.Connection.onOpen (/Users/joseph/Documents/Atom-files/node_modules/mongoose/lib/connection.js:494:5)
at /Users/joseph/Documents/Atom-files/node_modules/mongoose/lib/connection.js:453:10
at /Users/joseph/Documents/Atom-files/node_modules/mongoose/lib/drivers/node-mongodb-native/connection.js:59:5
at /Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/lib/db.js:206:5
at connectHandler (/Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/lib/server.js:272:7)
at g (events.js:199:16)
at emit (events.js:107:17)
at /Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/lib/topologies/server.js:374:23
at /Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/lib/topologies/server.js:730:13
at Callbacks.emit (/Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/lib/topologies/server.js:84:3)
at null.messageHandler (/Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/lib/topologies/server.js:219:23)
at Socket.<anonymous> (/Users/joseph/Documents/Atom-files/node_modules/mongoose/node_modules/mongodb/node_modules/mongodb-core/lib/connection/connection.js:259:22)
14 May 21:02:09 - [nodemon] app crashed - waiting for file changes before starting...
最佳答案
您要编译架构两次,其中一次是在定义方法之前。这一行具体是:
var Kitten = mongoose.model('Kitten', kittySchema)
您需要等到定义了 kittySchema.methods
之后再用 mongoose.model
编译它。您自己的代码注释告诉您不要这样做 :)
此外,为了将来引用,您粘贴的 TypeError: undefined is not a function
错误没有多大用处,但它下面的调用堆栈很有用,它指出了蓬松的 没有方法“说”
。
关于javascript - Mongoose 小猫示例不起作用,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/30244618/