The Mongoose Schema API Connection.prototype.id of the Mongoose API is used on the Connection objects. It allows us to check how many connections does connection object poses. It is used to debug the connection object when we have multiple connections pointing to one single connection reference. Let us understand the id property using an example.
Syntax:
connectionObject.id;
Parameters: This property does not accept any parameters.
Return Value: This property returns a number that represents the number of database connection of the particular connection object.
Setting up Node.js application:
Step 1: Create a Node.js application using the following command:
npm init
Step 2: After creating the NodeJS application, Install the required module using the following command:
npm install mongoose
Project Structure: The project structure will look like this:
Example 1: In this example, we are illustrating the functionality of id property on the connection object. We have created 3 connections that are pointing to the same variable and at the end with the help of id property, we verify the number of connections pointing to the connectionObject variable.
Filename: app.js
// Require mongoose module const mongoose = require( "mongoose" );
// Set Up the Database connection let connectionObject = mongoose.createConnection(URI, { useNewUrlParser: true ,
useUnifiedTopology: true ,
}); connectionObject = mongoose.createConnection(URI, { useNewUrlParser: true ,
useUnifiedTopology: true ,
}); connectionObject = mongoose.createConnection(URI, { useNewUrlParser: true ,
useUnifiedTopology: true ,
}); console.log(connectionObject.id) |
Step to run the program: To run the application execute the below command from the root directory of the project:
node app.js
Output:
3
Example 2: In this example, we are illustrating the functionality of id property on connection object.
Filename: app.js
// Require mongoose module const mongoose = require( "mongoose" );
// Set Up the Database connection const connectionObject = mongoose.createConnection(URI); console.log(connectionObject.id) |
Step to run the program: To run the application execute the below command from the root directory of the project:
node app.js
Output:
1
Reference: https://mongoosejs.com/docs/api/connection.html#connection_Connection-id