Add enableKeepAlive property to ConnectionOptions interface

[luisasalas]

Noticed enableKeepAlive is missing on Connection.d.ts

[wellwelwel]

Comparing the ConnectionOptions and validOptions, both enableKeepAlive and keepAliveInitialDelay options are missing. Instead, they are in PoolOptions:

node-mysql2/typings/mysql/lib/Pool.d.ts

Lines 41 to 49 in 8831e09

	/**
	* Enable keep-alive on the socket. (Default: true)
	*/
	enableKeepAlive?: boolean;
	/**
	* If keep-alive is enabled users can supply an initial delay. (Default: 0)
	*/
	keepAliveInitialDelay?: number;

[luisasalas]

@wellwelwel I assumed they should be since they are defined in ConnectionConfig?

node-mysql2/lib/connection_config.js

Lines 120 to 121 in 8831e09

	this.enableKeepAlive = options.enableKeepAlive !== false;
	this.keepAliveInitialDelay = options.keepAliveInitialDelay || 0;

[wellwelwel]

I assumed they should be since they are defined in ConnectionConfig?

@luisasalas, yes, considering the typings consistency with the source code, the ideal would be to move them from PoolOptions to ConnectionOptions.

---

Also:

node-mysql2/lib/connection_config.js

Line 29 in 8831e09

enableKeepAlive: 1,

node-mysql2/lib/connection_config.js

Line 35 in 8831e09

keepAliveInitialDelay: 1,

[wellwelwel]

Gotcha, I see it's default to true. However, when using this library in typescript, if we wanted to pass in false, would it be ignored since it's not defined in the typings?

It should work as usual ✅

When using TypeScript, it will compile the code to JavaScript on build, then the /lib/connection_config.js is what will be considered instead of the Connection.d.ts.

Also, the declaration types from MySQL2 are separated from source code (neither depends on the other to work individually). Then these issues are really important to keep the typings consistent with the source code 🧑🏻‍🔧

[wellwelwel]

Fixed in v3.6.4 🙋🏻‍♂️

Now it will work for both createConnection, createPool and createPoolCluster:

import mysql, { PoolOptions, ConnectionOptions } from 'mysql2';

const poolOptions: PoolOptions = {
  enableKeepAlive: true,
  keepAliveInitialDelay: 0,
}

const connectionOptions: ConnectionOptions = {
  enableKeepAlive: true,
  keepAliveInitialDelay: 0,
}

mysql.createConnection(connectionOptions);
mysql.createPool(poolOptions);
mysql.createPoolCluster().add(poolOptions);

• The same for mysql2/promise