Client vs Server - SSG Fallback=true

[jaybytez]

One of the part as a newbie to the framework that is totally confusing to me is the discussion about client vs server code. Like in a logging framework, trying to find one that can log statements and determine if they are server side and can be logged to a file. Discussions and docs say getStaticProps/getStaticPath only run during build time, but with fallback=true, it seems like they run server side when receiving a runtime dynamic route.

Is there a clean way to understand if the context of the function is server vs client? Are getStaticPaths/getStaticProps with fallback=true server side then and everything else in the component is client side?

And is there a logging framework that can determine that as well where it takes a single log statement and determines if it is client it goes to console otherwise it logs to file?