Javascript 在evennode.com的真实主机上使用mongodb时出现问题

我刚刚将我的第一个项目上传到evennode中的一个免费node.js主机上，但它不起作用。我把我所有的连接代码都改成了evennode推荐的代码，但我不能使用express，因为基本上我所有的代码都与之配套。有人知道我应该如何配置连接吗？对不起，我的英语不是很好。这是我在StackOverflow的第一个问题：）

这是我的app.js代码

var express = require('express');
var mongoose = require('mongoose');
var khatm = require('./khatm');
var app = express();
var bodyParser = require('body-parser');

var url = "mongodb://localhost:27017/khatm";


app.use(bodyParser.urlencoded({extended: false}));

mongoose.connect(url, {useUnifiedTopology: true, useNewUrlParser: true, useCreateIndex: true}, 
function (e) {
    if (!e) {
    console.log("connect");
} else {
    console.log("not connected")
}
});
  app.use('/khatm', khatm);
  app.listen(3000);

日志说：

2020-07-28 13:10:15 fbe827e2fb50 MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017
2020-07-28 13:10:15 fbe827e2fb50     at NativeConnection.Connection.openUri (/data/app/node_modules/mongoose/lib/connection.js:828:32)
2020-07-28 13:10:15 fbe827e2fb50     at Mongoose.connect (/data/app/node_modules/mongoose/lib/index.js:335:15)
2020-07-28 13:10:15 fbe827e2fb50     at Object.<anonymous> (/data/app/app.js:12:10)
2020-07-28 13:10:15 fbe827e2fb50     at Module._compile (internal/modules/cjs/loader.js:1133:30)
2020-07-28 13:10:15 fbe827e2fb50     at Object.Module._extensions..js (internal/modules/cjs/loader.js:1153:10)
2020-07-28 13:10:15 fbe827e2fb50     at Module.load (internal/modules/cjs/loader.js:977:32)
2020-07-28 13:10:15 fbe827e2fb50     at Function.Module._load (internal/modules/cjs/loader.js:877:14)
2020-07-28 13:10:15 fbe827e2fb50     at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)
2020-07-28 13:10:15 fbe827e2fb50     at internal/main/run_main_module.js:18:47 {
2020-07-28 13:10:15 fbe827e2fb50   reason: TopologyDescription {
2020-07-28 13:10:15 fbe827e2fb50     type: 'Single',
2020-07-28 13:10:15 fbe827e2fb50     setName: null,
2020-07-28 13:10:15 fbe827e2fb50     maxSetVersion: null,
2020-07-28 13:10:15 fbe827e2fb50     maxElectionId: null,
2020-07-28 13:10:15 fbe827e2fb50     servers: Map { 'localhost:27017' => [ServerDescription] },
2020-07-28 13:10:15 fbe827e2fb50     stale: false,
2020-07-28 13:10:15 fbe827e2fb50     compatible: true,
2020-07-28 13:10:15 fbe827e2fb50     compatibilityError: null,
2020-07-28 13:10:15 fbe827e2fb50     logicalSessionTimeoutMinutes: null,
2020-07-28 13:10:15 fbe827e2fb50     heartbeatFrequencyMS: 10000,
2020-07-28 13:10:15 fbe827e2fb50     localThresholdMS: 15,
2020-07-28 13:10:15 fbe827e2fb50     commonWireVersion: null
2020-07-28 13:10:15 fbe827e2fb50   }
2020-07-28 13:10:15 fbe827e2fb50 }

日志说：

2020-07-28 12:49:26 35e6f679b632 MongooseServerSelectionError: Authentication failed.
2020-07-28 12:49:26 35e6f679b632     at NativeConnection.Connection.openUri (/data/app/node_modules/mongoose/lib/connection.js:828:32)
2020-07-28 12:49:26 35e6f679b632     at Mongoose.connect (/data/app/node_modules/mongoose/lib/index.js:335:15)
2020-07-28 12:49:26 35e6f679b632     at Object.<anonymous> (/data/app/app.js:13:10)
2020-07-28 12:49:26 35e6f679b632     at Module._compile (internal/modules/cjs/loader.js:1133:30)
2020-07-28 12:49:26 35e6f679b632     at Object.Module._extensions..js (internal/modules/cjs/loader.js:1153:10)
2020-07-28 12:49:26 35e6f679b632     at Module.load (internal/modules/cjs/loader.js:977:32)
2020-07-28 12:49:26 35e6f679b632     at Function.Module._load (internal/modules/cjs/loader.js:877:14)
2020-07-28 12:49:26 35e6f679b632     at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)
2020-07-28 12:49:26 35e6f679b632     at internal/main/run_main_module.js:18:47 {
2020-07-28 12:49:26 35e6f679b632   reason: TopologyDescription {
2020-07-28 12:49:26 35e6f679b632     type: 'ReplicaSetNoPrimary',
2020-07-28 12:49:26 35e6f679b632     setName: null,
2020-07-28 12:49:26 35e6f679b632     maxSetVersion: null,
2020-07-28 12:49:26 35e6f679b632     maxElectionId: null,
2020-07-28 12:49:26 35e6f679b632     servers: Map {
2020-07-28 12:49:26 35e6f679b632       '9a.mongo.evennode.com:27017' => [ServerDescription],
2020-07-28 12:49:26 35e6f679b632       '9b.mongo.evennode.com:27017' => [ServerDescription]
2020-07-28 12:49:26 35e6f679b632     },
2020-07-28 12:49:26 35e6f679b632     stale: false,
2020-07-28 12:49:26 35e6f679b632     compatible: true,
2020-07-28 12:49:26 35e6f679b632     compatibilityError: null,
2020-07-28 12:49:26 35e6f679b632     logicalSessionTimeoutMinutes: null,
2020-07-28 12:49:26 35e6f679b632     heartbeatFrequencyMS: 10000,
2020-07-28 12:49:26 35e6f679b632     localThresholdMS: 15,
2020-07-28 12:49:26 35e6f679b632     commonWireVersion: null
2020-07-28 12:49:26 35e6f679b632   }
2020-07-28 12:49:26 35e6f679b632 }

2020-07-28 12:49:26 35e6f679b632 MongooseServerSelectionError:身份验证失败。
2020-07-28 12:49:26位于NativeConnection.Connection.openUri（/data/app/node_modules/mongoose/lib/Connection.js:828:32）的35e6f679b632
2020-07-28 12:49:26 Mongoose.connect上的35e6f679b632（/data/app/node_modules/Mongoose/lib/index.js:335:15）
2020-07-28 12:49:26 35e6f679b632目标。（/data/app/app.js:13:10）
2020-07-28 12:49:26 35e6f679b632 at模块编译（internal/modules/cjs/loader.js:1133:30）
2020-07-28 12:49:26 35e6f679b632 at Object.Module._extensions..js（internal/modules/cjs/loader.js:1153:10）
2020-07-28 12:49:26 35e6f679b632 at Module.load（内部/modules/cjs/loader.js:977:32）
2020-07-28 12:49:26 35e6f679b632 at功能模块加载（内部/modules/cjs/loader.js:877:14）
2020-07-28 12:49:26 35e6f679b632在Function.executeUserEntryPoint[作为runMain]（内部/modules/run_main.js:74:12）
2020-07-28 12:49:26 35e6f679b632内部/主/运行主模块。js:18:47{
2020-07-28 12:49:26 35e6f679b632原因：地形描述{
2020-07-28 12:49:26 35e6f679b632类型：“ReplicateSetNoPrimary”，
2020-07-28 12:49:26 35e6f679b632集名：空，
2020-07-28 12:49:26 35e6f679b632 maxSetVersion:空，
2020-07-28 12:49:26 35e6f679b632 maxElectionId:null，
2020-07-28 12:49:26 35e6f679b632服务器：地图{
2020-07-28 12:49:26 35e6f679b632'9a.mongo.evennode.com:27017'=>[ServerDescription]，
2020-07-28 12:49:26 35e6f679b632'9b.mongo.evennode.com:27017'=>[服务器描述]
2020-07-28 12:49:26 35e6f679b632}，
2020-07-28 12:49:26 35e6f679b632过时：错误，
2020-07-28 12:49:26 35e6f679b632兼容：正确，
2020-07-28 12:49:26 35e6f679b632兼容性错误：空，
2020-07-28 12:49:26 35e6f679b632 logicalSessionTimeoutMinutes:空，
2020-07-28 12:49:26 35e6f679b632心跳频率：10000，
2020-07-28 12:49:26 35e6f679b632本地阈值ms:15，
2020-07-28 12:49:26 35e6f679b632公共线路版本：空
2020-07-28 12:49:26 35e6f679b632}
2020-07-28 12:49:26 35e6f679b632}

---

所有提示将不胜感激。谢谢你

这个问题有点老了，在这里回答它以防对其他人有所帮助：我一步一步地重复了提问人的问题（这也是问题所在），我的应用程序运行并成功连接

您确定在admin.evennode.com的“信息”页面为您的应用程序设置了Mongodb的密码吗

---

在页面底部的MongoDB部分有一个“更改密码”的链接。

Hi！evennode是否有任何特定的错误日志？@tunmee Hi.errors是不同的。例如，当我使用他们的代码时，它会运行，但我无法访问express和app.khatm。正如您所看到的，一些代码位于另一个名为khatm的文件中，当我使用我的代码时，日志显示未连接，我将添加问题。

2020-07-28 12:49:26 35e6f679b632 MongooseServerSelectionError: Authentication failed.
2020-07-28 12:49:26 35e6f679b632     at NativeConnection.Connection.openUri (/data/app/node_modules/mongoose/lib/connection.js:828:32)
2020-07-28 12:49:26 35e6f679b632     at Mongoose.connect (/data/app/node_modules/mongoose/lib/index.js:335:15)
2020-07-28 12:49:26 35e6f679b632     at Object.<anonymous> (/data/app/app.js:13:10)
2020-07-28 12:49:26 35e6f679b632     at Module._compile (internal/modules/cjs/loader.js:1133:30)
2020-07-28 12:49:26 35e6f679b632     at Object.Module._extensions..js (internal/modules/cjs/loader.js:1153:10)
2020-07-28 12:49:26 35e6f679b632     at Module.load (internal/modules/cjs/loader.js:977:32)
2020-07-28 12:49:26 35e6f679b632     at Function.Module._load (internal/modules/cjs/loader.js:877:14)
2020-07-28 12:49:26 35e6f679b632     at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)
2020-07-28 12:49:26 35e6f679b632     at internal/main/run_main_module.js:18:47 {
2020-07-28 12:49:26 35e6f679b632   reason: TopologyDescription {
2020-07-28 12:49:26 35e6f679b632     type: 'ReplicaSetNoPrimary',
2020-07-28 12:49:26 35e6f679b632     setName: null,
2020-07-28 12:49:26 35e6f679b632     maxSetVersion: null,
2020-07-28 12:49:26 35e6f679b632     maxElectionId: null,
2020-07-28 12:49:26 35e6f679b632     servers: Map {
2020-07-28 12:49:26 35e6f679b632       '9a.mongo.evennode.com:27017' => [ServerDescription],
2020-07-28 12:49:26 35e6f679b632       '9b.mongo.evennode.com:27017' => [ServerDescription]
2020-07-28 12:49:26 35e6f679b632     },
2020-07-28 12:49:26 35e6f679b632     stale: false,
2020-07-28 12:49:26 35e6f679b632     compatible: true,
2020-07-28 12:49:26 35e6f679b632     compatibilityError: null,
2020-07-28 12:49:26 35e6f679b632     logicalSessionTimeoutMinutes: null,
2020-07-28 12:49:26 35e6f679b632     heartbeatFrequencyMS: 10000,
2020-07-28 12:49:26 35e6f679b632     localThresholdMS: 15,
2020-07-28 12:49:26 35e6f679b632     commonWireVersion: null
2020-07-28 12:49:26 35e6f679b632   }
2020-07-28 12:49:26 35e6f679b632 }