使用Mongoskin和MongoHQ和Node.js部署到Heroku時遇到問題

Question

我目前正在構建一個使用mongoskin的node / express.js應用程序。 我最近將我的應用程序部署到了Heroku，並且由於將mongohq與我的應用程序結合使用而感到頭疼。

這是我與節點app.js一起運行的app.js文件

var express = require("express");
var app = express();
decks = require('./routes/decks');
app.get('/decks', decks.findAll);

我的package.json：

{
    "name": "blah blah",
    "description": "Why are there so my blah blah",
    "version": "0.0.1",
    "private": true,
    "dependencies": {
        "express": "3.x",
        "mongodb": "1.1.8",
        "socket.io": "0.9.10"
    },
    "engines": {
        "node": "0.8.4",
        "npm": "1.1.49"
    }
}

閱讀了有關Heroku的指南后，我嘗試重新構建decks.js並像這樣使用mongoskin。

var mongo = require('mongoskin'); 
var mongoUri = process.env.MONGOHQ_URL;
var db = mongo.db(mongoUri);

exports.findById = function(req, res) {
     var id = req.params.id;
     console.log('Retrieving deck: ' + id);
     db.collection('decks', function(err, collection) {
         collection.findOne({'_id':new BSON.ObjectID(id)}, function(err, item) {
             res.send(item);
         });
     });
 };

但是我一直在得到錯誤：

 Please ensure that you set the default write concern for the database by setting    =
=   one of the options                                                                 =
=                                                                                      =
=     w: (value of > -1 or the string 'majority'), where < 1 means                     =
=        no write acknowlegement                                                       =
=     journal: true/false, wait for flush to journal before acknowlegement             =
=     fsync: true/false, wait for flush to file system before acknowlegement           =
=                                                                                      =
=  For backward compatibility safe is still supported and                              =
=   allows values of [true | false | {j:true} | {w:n, wtimeout:n} | {fsync:true}]      =
=   the default value is false which means the driver receives does not                =
=   return the information of the success/error of the insert/update/remove            =
=                                                                                      =
=   ex: new Db(new Server('localhost', 27017), {safe:false})                           =
=                                                                                      =
=   http://www.mongodb.org/display/DOCS/getLastError+Command                           =
=                                                                                      =
=  The default of no acknowlegement will change in the very near future                =
=                                                                                      =
=  This message will disappear when the default safe is set on the driver Db           =
========================================================================================

我讀了很多教程，但是我無法使數據庫正常工作！ 請任何幫助，您將不勝感激。

Answer 1

您的Db對象正在使用不建議使用的設置：“安全”。

如果將“ w”選項設置為所需的寫關注點，則該錯誤應消失。

這是用於實例化該Db對象的文檔的鏈接。

http://mongodb.github.io/node-mongodb-native/api-generation/db.html

...

哦，您可以嘗試將uri變量更新為process.env.MONGOHQ_URL：P

Answer 2

社長說的對

修改此行：

var db = mongo.db(mongoUri);

對此：

var db = mongo.db(mongoUri, {w:1});

這將使您在對數據庫執行操作時寫確認，並使錯誤消失

有關寫問題的更多信息，請查看此鏈接