node.js 检查猫鼬连接状态而不创建新连接
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Check mongoose connection state without creating new connection
提问by cyberwombat
I have some tests - namely Supertest - that load my Express app. This app creates a Mongoose connection. I would like to know how to check the status of that connection from within my test.
我有一些测试 - 即 Supertest - 加载我的 Express 应用程序。这个应用程序创建了一个猫鼬连接。我想知道如何从我的测试中检查该连接的状态。
In app.js
在 app.js 中
mongoose.connect(...)
In test.js
在 test.js 中
console.log(mongoose.connection.readyState);
How to access the app.js connection? If I connect using the same parameters in test.js will that create a new connection or look for existing one?
如何访问 app.js 连接？如果我在 test.js 中使用相同的参数进行连接，会创建一个新连接还是查找现有连接？
回答by robertklep
Since the mongoose module exports a singleton object, you don't have to connect in your test.jsto check the state of the connection:
由于 mongoose 模块导出一个单例对象，因此您不必在您的连接中test.js检查连接状态：
// test.js
require('./app.js'); // which executes 'mongoose.connect()'
var mongoose = require('mongoose');
console.log(mongoose.connection.readyState);
ready states being:
就绪状态是：
- 0: disconnected
- 1: connected
- 2: connecting
- 3: disconnecting
- 0：断开
- 1：连接
- 2：连接
- 3：断开连接
回答by englishPete
I use this for my Express Server mongoDB status, where I use the express-healthcheck middleware
我将它用于我的 Express Server mongoDB 状态，在那里我使用了 express-healthcheck 中间件
// Define server status
const mongoose = require('mongoose');
const serverStatus = () => {
return {
state: 'up',
dbState: mongoose.STATES[mongoose.connection.readyState]
}
};
// Plug into middleware.
api.use('/api/uptime', require('express-healthcheck')({
healthy: serverStatus
}));
Gives this in a Postman request when the DB is connected.
当数据库连接时，在 Postman 请求中给出这个。
{
"state": "up",
"dbState": "connected"
}
Gives this response when the database was shutdown.
当数据库关闭时给出此响应。
{
"state": "up",
"dbState": "disconnected"
}
(The "up" in the responses represent my Express Server status)
（响应中的“up”代表我的 Express Server 状态）
Easy to read (no numbers to interpret)
易于阅读（无需解释数字）
