How to check if a connection is still established to the database using TypeORM?

Question

I'm using typeorm "typeorm": "0.3.9" in a serverless architecture using AWS lambdas + RDS Proxy.

Following some suggestions I found on the internet, I chose to keep a connection open after the lambdas are executed so that it can be reused by the next lambda execution.

My problem is that there is a scenario where my RDS Proxy closes a connection (which it considers idle) but the reference of that connection is still being used by a lambda and then an error occurs.

To solve this problem I tried using typeorm to check if there is an active connection with the following code:

// Returns true even when the RDS Proxy has already killed the connection.
if (!this.dataSource.isInitialized) {
  await this.dataSource.initialize();
}

When I tested it I noticed that this validation understands that there is an established connection even when the RDS Proxy has already killed the connection.

Can anyone suggest me a way to check if there is an established connection to the database before opening a new connection?