我正在尝试运行 Addy Osmani 的书“Developing Backbone.js Applications”中的一些示例代码。一个练习提供了一个我曾经做过的 package.json 文件，npm install它安装了 Express、Mongoose 和 Path。从那里我node server.js从同一个目录运行，它给了我这个错误：
Express server listening on port 4711 in development mode
events.js:72
throw er; // Unhandled 'error' event
^
Error: failed to connect to [localhost:27017]
at null.<anonymous> (C:\backbone-fundamentals\exercise-2\node_modules\mongoose\node_modules\mongodb\lib\mongodb\connection\server.js:648:74)
...
at process._tickCallback (node.js:415:13)
我假设它在连接到 Mongoose DB 时遇到问题，但作为 Node.js、Express 或 Mongoose 的业余爱好者，我不知道从哪里开始调试它。如何检查 Mongoose 是否安装正确？顺便说一句，我在 Windows 上。
如果您有兴趣，这里是 Node 的整个 server.js 文件：
'use strict';
// 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();
//Connect to database
mongoose.connect( 'mongodb://localhost/library_database' );
//Schemas
var Keywords = new mongoose.Schema({
keyword: String
});
var Book = new mongoose.Schema({
title: String,
author: String,
releaseDate: Date,
keywords: [ Keywords ]
});
//Models
var BookModel = mongoose.model( 'Book', Book );
// 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 }));
});
// Routes
app.get( '/api', function( request, response ) {
response.send( 'Library API is running' );
});
//Get a list of all books
app.get( '/api/books', function( request, response ) {
return BookModel.find( function( err, books ) {
if( !err ) {
return response.send( books );
} else {
return console.log( err );
}
});
});
//Get a single book by id
app.get( '/api/books/:id', function( request, response ) {
return BookModel.findById( request.params.id, function( err, book ) {
if( !err ) {
return response.send( book );
} else {
return console.log( err );
}
});
});
//Insert a new book
app.post( '/api/books', function( request, response ) {
var book = new BookModel({
title: request.body.title,
author: request.body.author,
releaseDate: request.body.releaseDate,
keywords: request.body.keywords
});
book.save( function( err ) {
if( !err ) {
return console.log( 'created' );
} else {
return console.log( err );
}
});
return response.send( book );
});
//Update a book
app.put( '/api/books/:id', function( request, response ) {
console.log( 'Updating book ' + request.body.title );
return BookModel.findById( request.params.id, function( err, book ) {
book.title = request.body.title;
book.author = request.body.author;
book.releaseDate = request.body.releaseDate;
book.keywords = request.body.keywords;
return book.save( function( err ) {
if( !err ) {
console.log( 'book updated' );
} else {
console.log( err );
}
return response.send( book );
});
});
});
//Delete a book
app.delete( '/api/books/:id', function( request, response ) {
console.log( 'Deleting book with id: ' + request.params.id );
return BookModel.findById( request.params.id, function( err, book ) {
return book.remove( function( err ) {
if( !err ) {
console.log( 'Book removed' );
return response.send( '' );
} else {
console.log( err );
}
});
});
});
//Start server
var port = 4711;
app.listen( port, function() {
console.log( 'Express server listening on port %d in %s mode', port, app.settings.env );
});