Update usage instructions for Flatpak

[guihkx]

This simplifies things regarding the Flatpak set up.

Rendered page: https://github.com/guihkx/spotify-adblock/blob/readme-flatpak/README.md

Closes #112

[guihkx]

Apologies for the extra force-pushes. It should be ready for review now.

[axelsimon]

@guihkx small mistake in your instructions.

mkdir -p ~/.var/app/com.spotify.Client/config/spotify-adblock
but then:
cp config.toml ~/.var/app/com.spotify.Client/spotify-adblock

/config is missing, the right command is:
cp config.toml ~/.var/app/com.spotify.Client/config/spotify-adblock

Also, i'm not sure i like telling people they just need to use podman to build. At least we should give people the option: either you need cargo + rust, or if you don't want to install that you can run a container using podman (why Ubuntu 23.10 though, at least use a LTS or a recent version). But then again you can also use nix and nix-shell -p cargo so, i'm not sure we should push flatpak users to a specific solution.

[axelsimon]

Needed change.

[guihkx]

Also, i'm not sure i like telling people they just need to use podman to build.

That's necessary because building this library on a distro that has a different glibc version than the one provided by the Freedesktop Runtime (which Spotify for Flatpak runs on), may cause the library not to work (see #24 and #28).

And that's the reason why Ubuntu 23.10 was chosen: It has glibc 2.38, which is the same version present in the 23.08 Freedesktop Runtime, which was used by Spotify when I created this pull request, but now they've updated to 24.08, so I'll need to find another distro with the same glibc version...

i'm not sure we should push flatpak users to a specific solution.

I'm done because it's the solution that I tested and it's guaranteed work. People are, of course, free to choose whatever build methods they like. Or they can avoid the build process completely and try their luck with the pre-built library, but again, I can't guarantee that will work...

[guihkx]

Updates:

• Fixed the cp config.toml ... command not targeting the right location.
• Updated the Flatpak-specific build instructions to use a Ubuntu 24.10 container image, since it has glibc 2.40, which matches the version used by the runtime Spotify for Flatpak currently runs on (24.08).

[guihkx]

I'm so sorry, I deleted the branch by mistake while I was pushing changes to this other branch I'm working on.

[abba23]

Flatpak-specific build instructions.

I think telling people to build the project using podman/docker adds a big dependency, complexity and potential issues from first-time users trying to set it up in their environment. Since I don't use Flatpak myself, I can't verify, maintain or help people having problems with these instructions either.

So to be perfectly honest, I'd rather remove the Flatpak instructions altogether in order to avoid even more related issues collecting dust, than introduce new potential sources for them. They're just frustrating for both me who can't help and the users who likely won't get any answer in a useful time frame.

Remove every $ at the beginning of each command for easier copying and pasting.

This seems like something that should have been in a separate PR. Either way I'm not convinced that removing the $s is a good idea, because the easier copying comes at the cost of readability (making it immediately obvious that it's a shell command) and clarity ($ indicating the command should be run in a user shell as opposed to a root shell, which would be indicated by a #).

[guihkx]

I think telling people to build the project using podman/docker adds a big dependency, complexity and potential issues from first-time users trying to set it up in their environment.

Even though I disagree, I've now removed the build instructions for Flatpak.

Alas, as already stated in the README, if Flatpak users use the .so library you provide, or even if they build manually using the host's Rust compiler, it might not work with the Flatpak runtime due to potentially different glibc versions (see #24 and #28).

This would be solved by building the library with Podman/Docker using a container that has the same glibc version used by the Flatpak runtime used by the Spotify app.

Since I don't use Flatpak myself, I can't verify, maintain or help people having problems with these instructions either.

I guarantee they work, but I also understand what you're saying. The build instructions for Flatpak would also have to be updated yearly (i.e., when they move to a newer runtime, which is released once a year).

Either way I'm not convinced that removing the $s is a good idea, because the easier copying comes at the cost of readability

Alright, I've added them back.