Using `authOptional` in `:api` pipelines about auth_plug

[LuchoTurtle]

Just created #102 to briefly explain how to use this package with APIs. Nothing biggie, just a clarification.

[nelsonic]

@LuchoTurtle great question, thank you for asking/opening it. 👌
I’ve wondered the same in the past and opted for allowing each consuming app to implement the :fetch_session but if there was no negative side effect of doing it in auth_plug is be happy to include it in the library. 💭

[LuchoTurtle]

I've pondered about this and tried to find a way to handle this but perhaps it's best for the user to do the fetching of the session themselves.

Auth_plug shouldn't fetch the session just to verify if it exists. This will cause fetching the session two times when using a browser pipeline, which is not really bueno.

[nelsonic]

Exactly. Thanks for confirming. 👌

[nelsonic]

@LuchoTurtle do you want to add a brief section on how to use auth_plug in an API pipeline to the README.md? 🙏

[nelsonic]

Thanks very much @LuchoTurtle 👍