Is there a method to check whether a file exists in the cache using its url?

## 💬 Questions and Help

Hi,

I've looked through the documentation, the issues on GitHub and source code.
I'd like to know, using its URL, if a file exists in the cache.

I've only found a private method in the cache manager's `CacheStore`: `_fileExists()`.
But since it's private, I cannot use it.

Any other suggestions?