c1d7714a21
WIP: currently just a simple setup that creates an empty git repo if it doesn’t exist yet, and writes a commit to it. A simple database backed by a bare git repository. WIP: Will speak a simple interactive protocol to query files and update them atomically. It could be made atomic on the git repo level, if a lock is taken between reading the current commit ref and creating the commit. Change-Id: I1fd30a046ac977063c3e08c36d96e835b35ff07d Reviewed-on: https://cl.tvl.fyi/c/depot/+/3046 Tested-by: BuildkiteCI Reviewed-by: Profpatsch <mail@profpatsch.de>
85 lines
2.8 KiB
Rust
85 lines
2.8 KiB
Rust
extern crate git2;
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use std::os::unix::ffi::OsStrExt;
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use std::path::PathBuf;
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const DEFAULT_BRANCH : &str = "refs/heads/main";
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fn main() {
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let git_db_dir = std::env::var_os("GIT_DB_DIR").expect("set GIT_DB_DIR");
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let git_db = PathBuf::from(git_db_dir).join("git");
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std::fs::create_dir_all(&git_db).unwrap();
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let repo = git2::Repository::init_opts(
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&git_db,
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git2::RepositoryInitOptions::new()
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.bare(true)
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.mkpath(true)
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.description("git-db database")
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.initial_head(DEFAULT_BRANCH)
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).expect(&format!("unable to create or open bare git repo at {}", &git_db.display()));
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let mut index = repo.index().expect("cannot get the git index file");
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eprintln!("{:#?}", index.version());
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index.clear().expect("could not clean the index");
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let now = std::time::SystemTime::now()
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.duration_since(std::time::SystemTime::UNIX_EPOCH)
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.expect("unable to get system time");
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let now_git_time = git2::IndexTime::new(
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now.as_secs() as i32, // lol
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u32::from(now.subsec_nanos()),
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);
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let data = "hi, it’s me".as_bytes();
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index.add_frombuffer(
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&git2::IndexEntry {
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mtime: now_git_time,
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ctime: now_git_time,
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// don’t make sense
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dev: 0,
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ino: 0,
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mode: /*libc::S_ISREG*/ 0b1000 << (3+9) | /* read write for owner */ 0o644,
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uid: 0,
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gid: 0,
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file_size: data.len() as u32, // lol again
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id: git2::Oid::zero(),
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flags: 0,
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flags_extended: 0,
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path: "hi.txt".as_bytes().to_owned(),
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},
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data
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).expect("could not add data to index");
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let oid = index.write_tree().expect("could not write index tree");
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let to_add_tree = repo.find_tree(oid)
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.expect("we just created this tree, where did it go?");
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let parent_commits = match repo.find_reference(DEFAULT_BRANCH) {
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Ok(ref_) => vec![
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ref_
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.peel_to_commit()
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.expect(&format!("reference {} does not point to a commit", DEFAULT_BRANCH))
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],
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Err(err) => match err.code() {
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// no commit exists yet
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git2::ErrorCode::NotFound => vec![],
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_ => panic!("could not read latest commit from {}", DEFAULT_BRANCH),
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}
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};
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repo.commit(
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Some(DEFAULT_BRANCH),
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&git2::Signature::now("Mr. Authorboy", "author@example.com").unwrap(),
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&git2::Signature::now("Mr. Commiterboy", "committer@example.com").unwrap(),
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"This is my first commit!\n\
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\n\
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I wonder if it supports extended commit descriptions?\n",
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&to_add_tree,
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&parent_commits.iter().collect::<Vec<_>>()[..],
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).expect("could not commit the index we just wrote");
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}
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