The best practice in managing connections in MongoDB is to create a new connection when the application starts up and leave it open for the duration of the server’s lifetime.
Here is the process you’ll want to follow:
1. Establish Connection: Open a connection to the MongoDB server when your application starts. You can do this using the MongoDB clients provided for various programming languages (like Node.js, Python, Java, etc.). For example, in Node.js, you can use `MongoClient.connect()` function.
1. Connection pooling: MongoDB drivers (client libraries) support connection pooling. This means that they open several connections to the MongoDB server at the same time and reuse them for different operations, which improves application performance. The connection pool size can be configured according to your application needs.
1. Use the connection: Use this established connection to interact with the database throughout your application. You can perform read/write operations on this connection.
1. Exception Handling: If there’s an operation that encounters an exception, MongoDB will close that connection. Your application should be prepared to catch those exceptions, handle them and when needed, open new connections.
1. Close the connection: Usually, you should not close connection manually. Many MongoDB drivers handle connection recycling automatically to save resources. However, if your application is shutting down, it should close all connections to the MongoDB server using the right function provided in your MongoDB client. E.g., the `MongoClient.close()` function.
Remember, creating new connections is a time-consuming operation. So, reusing connections and connection pooling are key to improving application performance.
