EventEmitter memory leaks

[foysavas]

When using db-migrate programmatically for multiple databases, warnings are generated for EventEmitter leaks: Warning: Possible EventEmitter memory leak detected. 11 unhandledRejection listeners added.

Adding a unregisterEvents function to api.js should enable programmatic users to get around this. Such a function may also be used more generally to do proper cleanup.

Where registerEvent() is called:
https://github.com/db-migrate/node-db-migrate/blob/master/api.js#L136-L147

Where registerEvents() is defined:
https://github.com/db-migrate/node-db-migrate/blob/master/api.js#L136-L147

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[wzrdtales]

@foysavas Good catch.

In the case of programatic use it may be even unwanted right from the beginning to have those events being registered. They're only really targeted at the CLI, so the question is if just adding an unregister + disable them per configuration or if a db-migrate instance is created in the programatic mode, to disable those registers by default and give the option to register those controlling the process using db-migrate as a module.

[foysavas]

Agreed, especially given the process.exit() therein.

• A config option that enables or disables the registration of the listeners
• false as a default value for programmatic usage, true from the cli
• an unregisterEvent() that does cleanup

[killer-it44]

I just set the config option "throwUncatched" : true, and this won't register the handlers, and I believe it's the right thing to do for programmatic use. So from my perspective it can be closed.

Btw is "throwUncatched" maybe a typo? I am also not a native speaker, so not quite sure, but probably it should be "throwUncaught"?