feat: add more helper functions — radicle-ci-broker

The less these need to be duplicated between adapters, the better.

Signed-off-by: Lars Wirzenius liw@liw.fi

 /// Helper functions for writing adapters.
 pub mod helper {
     use std::{path::Path, process::Command};
     use radicle::prelude::{Profile, RepoId};
     use radicle_git_ext::Oid;
     use super::{MessageError, Request, Response, RunId, RunResult};
     /// Exit code to indicate we didn't get one from the process.
     pub const NO_EXIT: i32 = 999;
     /// Read a request from stdin.
     pub fn read_request() -> Result<Request, MessageHelperError> {
         let req =

         Ok(())
     }
     /// Get sources from the local node.
     pub fn get_sources(repoid: RepoId, commit: Oid, src: &Path) -> Result<(), MessageHelperError> {
         let profile = Profile::load().map_err(MessageHelperError::Profile)?;
         let storage = profile.storage.path();
         let repo_path = storage.join(repoid.canonical());
         git_clone(&repo_path, src)?;
         git_checkout(commit, src)?;
         Ok(())
     }
     /// Run `git clone` for the repository.
     fn git_clone(repo_path: &Path, src: &Path) -> Result<(), MessageHelperError> {
         runcmd(
             &[
                 "git",
                 "clone",
                 &repo_path.to_string_lossy(),
                 &src.to_string_lossy(),
             ],
             Path::new("."),
         )?;
         Ok(())
     }
     // Check out the requested commit.
     fn git_checkout(commit: Oid, src: &Path) -> Result<(), MessageHelperError> {
         runcmd(&["git", "config", "advice.detachedHead", "false"], src)?;
         runcmd(&["git", "checkout", &commit.to_string()], src)?;
         Ok(())
     }
     /// Run a program.
     pub fn runcmd(argv: &[&str], cwd: &Path) -> Result<i32, MessageHelperError> {
         assert!(!argv.is_empty());
         let output = Command::new("bash")
             .arg("-c")
             .arg(r#""$@" 2>&1"#)
             .arg("--")
             .args(argv)
             .current_dir(cwd)
             .output()
             .map_err(|err| MessageHelperError::Command("bash", err))?;
         let exit = output.status.code().unwrap_or(NO_EXIT);
         Ok(exit)
     }
     /// Possible errors from this module.
     #[derive(Debug, thiserror::Error)]
     pub enum MessageHelperError {

         /// Error writing response to stdout.
         #[error("failed to write response to stdout: {0:?}")]
         WriteResponse(Response, #[source] Box<MessageError>),
         /// Can't load Radicle profile.
         #[error("failed to load Radicle profile")]
         Profile(#[source] radicle::profile::Error),
         /// Can't run command and capture its output.
         #[error("failed to run command {0}")]
         Command(&'static str, #[source] std::io::Error),
     }
 }