chore: add devcontainer setup

[KnorpelSenf]

This add a devcontainer setup. It means that any contributor no longer has to install various solvers before being able to work on this repo. In addition, it can serve as a reference for the required system setup when somebody wants to use different solvers.

This extracts the system setup into a new build script which is used both to test CI and to create the container.

You can test the setup by opening the project inside the dev container and then building the crate.

Please let me know if something is not working out of the box.

[lovasoa]

Can we install the same packages as in https://github.com/rust-or/good_lp/blob/main/.github/workflows/rust.yml, and run the tests inside it ?

I fear that if the dev container is not tested, it will just silently break at some point in the future...

[KnorpelSenf]

I don't see a way to directly install GitHub Actions into a Docker container. Without the actions, there is no conda, and without conda, there is no scip, and without scip, we cannot run the tests.

Instead, what we could do is to duplicate the logic of the actions into a setup script that gives us a reproducible system setup. This script can then be run both in CI and during container setup. Would that be acceptable?

[KnorpelSenf]

This would actually have the advantage that all missing deps would be installed in the dev container

[lovasoa]

yes!

[KnorpelSenf]

Awesome, will do!

[KnorpelSenf]

@lovasoa I've noticed that russcip is able to ship a precompiled binary. Wouldn't it be much simpler if good_lp allowed developers to leverage this so that they don't have to install scip themselves? If yes, this would also drastically simplify the good_lp setup as we wouldn't have to install conda first.

[lovasoa]

@mmghannam what do you think ? What's the best way to depend on russcip from good-lp ?

[mmghannam]

Yes, I agree with @KnorpelSenf that it would simplify the developer experience greatly if another feature flag in good_lp would enable the bundled feature in russcip. I still wouldn't remove the current feature flag as that enables linking to a custom SCIP installation (or linking through conda).

[lovasoa]

Godd, let's do it that way: add a new flag to goodl-lp and use it on ci

[KnorpelSenf]

Nice! Please check out #72

[KnorpelSenf]

@lovasoa this is ready, please TAL

[lovasoa]

Do we really have to add #[cfg(any(feature = "scip", feature = "scip_bundled"))] everywhere we depend on scip? Can we have a base feature we test against?

[KnorpelSenf]

How about this?

[KnorpelSenf]

Also, something is still wrong with the container setup but I don't see it.

If you open the container and run cargo build, it fails with

$ cargo build
    Updating crates.io index
  Downloaded fnv v1.0.7
error: failed to open `/usr/local/cargo/registry/cache/index.crates.io-6f17d22bba15001f/fnv-1.0.7.crate`

Caused by:
  Permission denied (os error 13)

[KnorpelSenf]

Seems to be related to the cargo install command in the setup script, let me see how this can be fixed

[KnorpelSenf]

Done.

[lovasoa]

Thank you!