Question

我是Node.js的新手。所以我尝试使用parse-example将我的Node.js应用程序与Mongo DB连接起来。因此，在我安装完所有内容后，更改了Master和AppID（在Index.js和script.js中），我尝试启动我的应用程序（npm start），然后出现这些警告。

>     > parse-server-example@1.4.0 start C:\Users\TAASCTI5\temp\parseex\parse-server-e
>     xample
>     > node index.js
>     
>     DATABASE_URI not specified, falling back to localhost.
>     parse-server-example running on port 1337.
>     info: Parse LiveQuery Server starts running
>     warn: Unable to ensure uniqueness for usernames:  MongoError: failed to connect
>     to server [localhost:27017] on first connect
>         at Pool.<anonymous> (C:\Users\TAASCTI5\temp\parseex\parse-server-example\nod
>     e_modules\parse-server\node_modules\mongodb-core\lib\topologies\server.js:313:35
>     )
>         at emitOne (events.js:96:13)
>         at Pool.emit (events.js:188:7)
>         at Connection.<anonymous> (C:\Users\TAASCTI5\temp\parseex\parse-server-examp
>     le\node_modules\parse-server\node_modules\mongodb-core\lib\connection\pool.js:26
>     0:12)
>         at Connection.g (events.js:291:16)
>         at emitTwo (events.js:106:13)
>         at Connection.emit (events.js:191:7)
>         at Socket.<anonymous> (C:\Users\TAASCTI5\temp\parseex\parse-server-example\n
>     ode_modules\parse-server\node_modules\mongodb-core\lib\connection\connection.js:
>     162:49)
>         at Socket.g (events.js:291:16)
>         at emitOne (events.js:96:13)
>     warn: Unable to ensure uniqueness for user email addresses:  MongoError: failed
>     to connect to server [localhost:27017] on first connect
>         at Pool.<anonymous> (C:\Users\TAASCTI5\temp\parseex\parse-server-example\nod
>     e_modules\parse-server\node_modules\mongodb-core\lib\topologies\server.js:313:35
>     )
>         at emitOne (events.js:96:13)
>         at Pool.emit (events.js:188:7)
>         at Connection.<anonymous> (C:\Users\TAASCTI5\temp\parseex\parse-server-examp
>     le\node_modules\parse-server\node_modules\mongodb-core\lib\connection\pool.js:26
>     0:12)
>         at Connection.g (events.js:291:16)
>         at emitTwo (events.js:106:13)
>         at Connection.emit (events.js:191:7)
>         at Socket.<anonymous> (C:\Users\TAASCTI5\temp\parseex\parse-server-example\n
>     ode_modules\parse-server\node_modules\mongodb-core\lib\connection\connection.js:
>     162:49)
>         at Socket.g (events.js:291:16)
>         at emitOne (events.js:96:13)
>     (node:18132) UnhandledPromiseRejectionWarning: Unhandled promise rejection (reje
>     ction id: 4): MongoError: failed to connect to server [localhost:27017] on first
>      connect
>     (node:18132) UnhandledPromiseRejectionWarning: Unhandled promise rejection (reje
>     ction id: 5): MongoError: failed to connect to server [localhost:27017] on first
>      connect

结果是我无法使用错误500内部服务器错误连接到我的Mongo数据库。

Answer 1

当然，在你没有提供的代码中发现问题是猜测工作，但我认为从错误消息中可以明显看出你没有监听localhost：27017的Mongo数据库。

Answer 2

您没有提供数据库连接字符串（DATABASE_URI），因此服务器正在尝试连接到localhost。你在哪里托管你的MongoDB，你在哪里托管你的服务器？

在index.js文件中，您需要包含数据库连接字符串：

var databaseUri = mongodb://...;

希望有所帮助。

Node.js无法连接到Mongo DB

2 个答案: