这是我第一次使用猫鼬运行节点。我正在学习这本骨干书中的一些教程，并且我正在学习使用 express、mongoose 创建一个 restful api 的这一章，并且我正在按照我什至已经开始复制和粘贴的代码进行操作，但它仍然无法正常工作。这是代码：
http://addyosmani.github.io/backbone-fundamentals/#creating-the-back-end
// Module dependencies.
var application_root = __dirname,
express = require( 'express' ), //Web framework
path = require( 'path' ), //Utilities for dealing with file paths
mongoose = require( 'mongoose' ); //MongoDB integration
//Create server
var app = express();
// Configure server
app.configure( function() {
//parses request body and populates request.body
app.use( express.bodyParser() );
//checks request.body for HTTP method overrides
app.use( express.methodOverride() );
//perform route lookup based on url and HTTP method
app.use( app.router );
//Where to serve static content
app.use( express.static( path.join( application_root, 'site') ) );
//Show all errors in development
app.use( express.errorHandler({ dumpExceptions: true, showStack: true }));
});
//Start server
var port = 4711;
app.listen( port, function() {
console.log( 'Express server listening on port %d in %s mode', port, app.settings.env );
});
// Routes
app.get( '/api', function( request, response ) {
response.send( 'Library API is running' );
});
//Connect to database
mongoose.connect( 'mongodb://localhost/library_database');
//Schemas
var Book = new mongoose.Schema({
title: String,
author: String,
releaseDate: Date
});
//Models
var BookModel = mongoose.model( 'Book', Book );
我一直在寻找堆栈溢出和其他试图解决问题的网站，但我发现似乎没有任何东西可以让我连接到 mongodb。
第一个错误是：
events.js:72
throw er; // Unhandled 'error' event
^
Error: failed to connect to [localhost:27017]
at null.<anonymous> (/Users/jeff/Sites/backbone-ex2/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/server.js:536:74)
at EventEmitter.emit (events.js:106:17)
at null.<anonymous> (/Users/jeff/Sites/backbone-ex2/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/connection_pool.js:140:15)
at EventEmitter.emit (events.js:98:17)
at Socket.<anonymous> (/Users/jeff/Sites/backbone-ex2/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/connection.js:478:10)
at Socket.EventEmitter.emit (events.js:95:17)
at net.js:411:14
at process._tickCallback (node.js:415:13)
此更改似乎解决了该问题：
mongoose.connect( 'mongodb://localhost/library_database', function(err) { if (err) console.log(err); } );
在那之后，快递工作但mongodb无法连接：
Express server listening on port 4711 in development mode
[Error: failed to connect to [localhost:27017]]
我试着改成这样：
mongoose = require( 'mongoose' ).Mongoose;
我还尝试在 cli 中运行mongod，并对 cli 中的选项进行了一些更改，但这似乎只是打开了帮助页面。我完全被困住了......任何帮助将不胜感激。提前致谢。