# git

A small command-line-like Git module for Racket, implemented directly on top of the `libgit2` package.

```racket
(require git)

(git status)
(git add "main.rkt" "info.rkt")
(git commit "Implement raco support")
(git tag "v0.2")
(git checkout "main")
```

The same operations are available as normal procedures such as `git-status`, `git-add`, `git-commit`, `git-tag`, and `git-checkout`.

## HTTPS credentials

Version 0.2 adds persistent HTTPS credentials.  They are stored in the
`racket-git.ini` file in Racket's preferences directory.  Tokens are encrypted
with AES-GCM using a key derived from the store password with
PBKDF2-HMAC-SHA256.

Create the credential store once:

```racket
(git credentials init "store password")
```

Store a token for a Git host:

```racket
(git credentials set
     "https://git.dijkewijk.nl"
     "hans"
     token)
```

The host is used as the credential key, so the same entry is used for all HTTPS
repositories on that host.

The store is unlocked for one day by default:

```racket
(git credentials unlock "store password")
```

or for an explicit number of seconds:

```racket
(git credentials unlock "store password" (* 8 60 60))
```

The temporary unlock state is stored in `racket-git-unlock.ini` in Racket's
preferences directory, so it survives restarting DrRacket and starting a new
Racket process.  Both files are opened through `simple-ini` with `#:private? #t`; on Unix this
restricts them to mode 0600 before sensitive contents are written.  The cached
derived key grants access to the credentials until its expiry,
so `racket-git-unlock.ini` must be treated as sensitive during that period.

Lock immediately with:

```racket
(git credentials lock)
```

After credentials have been stored and the store is unlocked, normal remote
operations use them automatically:

```racket
(git fetch)
(git pull)
(git push)
```

## Supported Git operations

Version 0.2 supports repository discovery, init, clone, status, add, config,
commit, branch, checkout, lightweight tags, log, remotes, fetch,
fast-forward-only pull, push, tag push, and HTTPS username/token credentials.

SSH credentials, merge/rebase pull, annotated tags, and submodules are not yet
part of this module.

Install from the package directory with:

```sh
raco pkg install .
```