in src/cloud-sql-instance.ts [378:390]
addSocket(socket: DestroyableSocket) {
if (!this.instanceInfo.domainName) {
// This was not connected by domain name. Ignore all sockets.
return;
}
// Add the socket to the list
this.sockets.add(socket);
// When the socket is closed, remove it.
socket.once('closed', () => {
this.sockets.delete(socket);
});
}