A pool should be able to hand out both promise/non-promise wrapped connections

In several of my applications built using node-mysql2, I maintain a pool of connections in one module:

/db.js

import mysql from 'mysql2';
export const pool = mysql.createPool(mysqlURI);

In another module, I then use the pool to retrieve a connection, for operating on the connection in streaming mode, so I do this:

/module1.js

let con = pool.getConnection()
con.query("SELECT ...")
.on('result', ...)

In another module, I wish to use the pool to retrieve a connection, for operating on the connection in promise mode, so i'd like to do this:

/module2.js

let con = pool.getConnectionPromise()
con.query("SELECT ...")
.then( .... )

Unfortunately, because the pool only allows you to retrieve either a promise or non-promise wrapped connection, I need to create 2 different pools:

/db.js

import mysql from 'mysql2';
export const pool = mysql.createPool(mysqlURI);
export const poolPromise = mysql.createPoolPromise(mysqlURI);

It would be helpful if the non-promise pool allowed you to call getConnectionPromise, or queryPromise. Not all code is suited for use with promises, and maintaining two pools isn't ideal.

IMO their should only be one type of pool and you should decide when using it whether you want a promise wrapped connection/query or not

Trace the pool and connection APIs described in /db.js, /module1.js, and /module2.js, starting with getConnection and the promise-pool alternative. Determine how promise wrapping is selected today and define done as one pool supporting both callback/streaming and promise-based retrieval without requiring two pools. Verify the behavior with the project's relevant tests.