feat: add version flag to all the shims

[Mossaka]

This follows the PR containerd/rust-extensions#167

[jprendes]

suggestion: use https://crates.io/crates/git-version and remove the build scripts.

[Mossaka]

https://crates.io/crates/git-version uses git describe, which fetches the tag information for a commit hash. It is a bit awkward to have the following revision

./target/debug/containerd-shim-wasmedge-v1:
  Version: 0.1.1
  Revision: containerd-shim-wasm/v0.1.2-278-ged85c04-modified

[jprendes]

Could we use compile_time_run instead? With something like:

const fn get_rev() -> &'static str {
    compile_time_run::run_command_str!("sh", "-c", "echo -n $(git rev-parse --short=10 HEAD)$(git diff --quiet || echo .m)")
}

[jprendes]

suggestion: create a containerd_shim_wasm::run function that takes the version / revision, and handles this logic.

[Mossaka]

Sure

[Mossaka]

I don't think there is a good way to handle this in containerd-shim-wasm crate, as each shim implementation still needs to read os args, parse flags and get the version / revision... Could not save much logic here. With that said, I will leave it as is.

[jprendes]

I meant something like:

// somewhere in containerd-shim-wasm
pub fn run<Shim: ...>(runtime_id: &str, opts: Option<Config>, version: &str, revision: &str) {
    let os_args: Vec<_> = env::args_os().collect();
    let flags = parse(&os_args[1..]).unwrap();
    if flags.version {
        println!("{}:", os_args[0].to_string_lossy());
        println!("  Version: {}", env!("CARGO_PKG_VERSION"));
        println!("  Revision: {}", env!("CARGO_GIT_HASH"));
        println!();

        std::process::exit(0);
    }
    shim::run::<Shim>(runtime_id, opts)
}

and

// in main.rs
use containerd_shim_wasm::run;
fn main() {
    run::<ShimCli<WasiInstance>>(
        "io.containerd.wasmtime.v1",
        None,
        env!("CARGO_PKG_VERSION"),
        env!("CARGO_GIT_HASH"),
    );
}

then you can remove parse_version from all the lib.rs

[Mossaka]

Could we use compile_time_run instead? With something like:

I am a bit hesitate because it introduces an external library basically doing the same thing we want in build.rs, but less explictly.

[jprendes]

I am a bit hesitate because it introduces an external library basically doing the same thing we want in build.rs, but less explictly.

Haha, the opposite for me. I prefer the extra dep than adding a build.rs where it's not needed.
Also I think the extra dep is clearer and is less code to maintain (it has infrequent version bumps).
On the other hand, I'm not sure if that would work on Windows due to using sh / echo.
In any case, it's just a preference, and I'm happy for you to merge the build scripts.

[jprendes]

It's looking good. Some comments on ongoing discussions, but nothing major.

[Mossaka]

I will merge now! Thank you @jprendes