"ça a été" means "it went well or "this went well" so you can use it versatilely. There is often a hint of the thing could have gone wrong, bad or failed. It always refers to somethnig that has happened in the past. "ça" could refer to anything.
Exemples:
- after an interview, your friend can ask you : ça a été ? Meaning: did you do well during the interview?
If you did well, your answer can also be : oui, ça a été.
- after a fisrt day at school, you can ask your child/friend : ça a été ? Meaning: was this first day okay?
- after an holiday, you can ask somebody: ça a été tes vacances? Meaning: how was your holiday?
The same for your weekend, week, any event.
It is of course very spoken French, you will not write it in an essay or in a formal text.
J'espère que cette explication a été enrichissante,
Cordialement,
Carine.