What is the best approach to ignoring specific changes?

[tomenden]

I wonder what is the best way to achieve what I want, which sounds to me like a pretty common use case. Would love to get some advice 🙏

At a high level, I have an application that watches file changes in a specific folder. Files/dirs can be added/removed/modified.
Changes can be categorized into two categories:

1. Application changes - in some cases my application makes changes to the files under watch
2. External changes - in some cases, an external change may occur in the files under watch

I would like to be able to distinguish both types of changes.
In changes of type (1) I want to perform a different action from the one I need to perform in changes in type (2).

Currently, to do this, I hold a map of all files and directories in which I keep a last-modified timestamp and compare it using fs.Stats. This feels hacky and a lot of work for a feature I imagine is very much a common use case, but I might be mistaken.

Hopefully, my description of the problem is clear.
I would appreciate any advice!

Thanks in advance :)