fetch.rs

use git2::{RemoteCallbacks, Repository};
use simple_logger::SimpleLogger;
use std::{env, path::Path};

struct User {
    name: String,
    remote: String,
}

fn main() {
    SimpleLogger::new().init().unwrap();

    let garden = format!("{}/garden", env::var("HOME").unwrap());

    let user = User {
        name: "vera".to_string(),
        remote: "https://git.anagora.org/vera/notes".to_string(),
    };
    let repopath = format!("{}/{}", garden, user.name);

    let mut builder = git2::build::RepoBuilder::new();
    let mut fo = generate_fetchoptions(&user);
    builder.fetch_options(fo);
    let p = Path::new(&repopath);
    let repo = match builder.clone(&user.remote, p) {
        Ok(r) => r,
        Err(e) => match e.code() {
            git2::ErrorCode::Exists => {
                log::warn!("{}: Repo exists, skipping clone", e);
                Repository::open(&repopath).unwrap()
            }
            // something else unknown happened
            _ => panic!("{}", e),
        },
    };

    // regenerate fetch options
    fo = generate_fetchoptions(&user);
    let so = Some(&mut fo);

    let mut origin = repo.find_remote("origin").unwrap();
    origin.fetch(&["HEAD"], so, None).unwrap();
    let fetchref = repo.find_reference("FETCH_HEAD").unwrap();
    let commit = repo.reference_to_annotated_commit(&fetchref).unwrap();
    log::info!(
        "Current FETCH_HEAD for {} is sha: {}",
        user.name,
        commit.id()
    );
    let object = repo.find_object(commit.id(), None).unwrap();
    repo.reset(&object, git2::ResetType::Hard, None).unwrap();
}

//needed because fetch options don't implement Copy
fn generate_fetchoptions(user: &User) -> git2::FetchOptions {
    let mut callbacks = RemoteCallbacks::new();
    callbacks.transfer_progress({
        |p| {
            log::info!(
                "Fetch progress for {}: {}/{}",
                user.name,
                p.received_objects(),
                p.total_objects()
            );
            true
        }
    });

    let mut fo = git2::FetchOptions::new();
    fo.remote_callbacks(callbacks);
    fo
}