Api REST -> Best way for get an User id

[MeInTheGalaxie]

Hi,

I'm working with the Chamilo REST API, and I need to use a user's ID to be able to perform different actions.

What is the best way to get a user's ID via their "username" in your opinion?

[MeInTheGalaxie]

Good morning,
No one to give their opinion or experience on the question?