Better way for Connections? - node.js

Question

Currently, I have these lines of code littered all throughout my app.
Anytime, a GET or INSERT is called these lines are at the beginning of the function. So I feel like they are treated as a re-tryer to the DB. Could these just be put in the dbService class so that I don't have to connect to the?
and for reference: `` looks like this and this is all coming from
Any ideas on a proper way to do this? Would I have to create a re-tryer function in case my DB goes down?

Answer 1

Meet the singleton pattern :
// Wrapper around client to trigger reconnects
class PerpetualClient {
private client: Client = null
private async function createClient(): Client {
// However you create client
}
public getClient(){
return self.client;
}
public static async getPerpetualClient() : PerpetualClient{
let perpetualClient = new PerpetualClient();
const client = await PerpetualClient.createClient();
perpertualClient.client = client;
const reconnect = async ()=>{
const client = await PerpetualClient.createClient();
perpertualClient.client = client;
client.on('end',reconnect)
}
client.on('end',reconnect)
return perpertualClient;
}
}
// Class to enforce the single instantiation
class DBSingleton {
private reader: PerpetualClient = null
private writer: PerpetualClient = null
private static singleInstance: DBSingleton
private async startDB(){
DBSingleton.singleInstance = DBSingleton()
db.reader = await PerpetualClient.getPerpetualClient();
db.writer = await PerpetualClient.getPerpetualClient();
}
public async getDB(){
if(!DBSingleton.singleInstance){
await DBSingleton.startDB()
}
return DBSingleton.singleInstance;
}
}