Proposal: Add --version flag to print the build info of the binary

[Mossaka]

It would be nice to have a --version arg for the shims to be able to determine the build version information.

[Burning1020]

I agree. How much information that "--version" or "-version" should provide?
eg: name, version number, git commit id, rust version?

[Mossaka]

Hey @Burning1020 , thanks for your quick response! I am thinking about at least to provide information about the cargo version from env var like env!(CARGO_PKG_VERSION). It would be better to include information from git, like git commit SHA, last build datetime etc. I am not sure how useful Rust version would be in the binary though.

Here is an example of how to get these information from git in build time.

[Burning1020]

I see. Would you help commit this PR or I can do it lately (got other work to do now) ?

[Mossaka]

Sure I can give it a try. Do you think if it's reasonable to add a new flag to https:/containerd/rust-extensions/blob/main/crates/shim/src/args.rs#L24-L42?

Also, unrelated to this issue, but what do you think about using clap to build the CLI experience of the shim?

[Burning1020]

Sure I can give it a try. Do you think if it's reasonable to add a new flag to https:/containerd/rust-extensions/blob/main/crates/shim/src/args.rs#L24-L42?

Yes, maybe there is no other reasonable places.

Also, unrelated to this issue, but what do you think about using clap to build the CLI experience of the shim?

Clap doesn't support for short flag at present, see here:clap-rs/clap#2468 (comment), so it can't read the flags from containerd.