objgit
An experiment in storing git repositories in object storage. You probably don't need this. This is a proof of concept and doesn't really have a lot of uses yet.
This is heavily vibe coded as an exploration of the design space. See the claude plans folder for an idea of the kinds of things that were being explored and why. If this experiment ends up being shippable, a better implementation will be made to replace this terrible code.
License: MIT
Price: Free as in mattress. If you use this, it's your problem.
Notable features
- ssh, http, and git protocol support.
- post-receive hooks powered by userspace sandboxed shells and Kefka.
- basic prometheus metrics.
- no authentication whatsoever, if this ends up being actually useful then authentication will be implemented.
Design tradeoffs
- All repos are stored in object storage, making the local filesystem irrelevant at the cost of making storage operations a bit more latent compared to the local filesystem.
- Repos are stored in git bare repo format. This theoretically could hamper performance, but also means that in a pinch you can just download the repo from the object storage bucket should you need to get a copy of it RIGHT NOW.
- Post-receive hooks are stored in the repository, meaning that hooks are checked out from the repository on push.
- Right now all s3fs reads are completely buffered in memory before billy can use them, theoretically this means that the size limit for files is 2Gi.
- This is like very new and not tested in the slightest.
Future goals
- Integration with Tekton for CI pipelines.
- Some kind of web UI using the Xe Design System.
- Any kind of blogpost.
- Deployment to Kubernetes.
- HTTPS support with TLS termination.
Setup instructions
objgit depends on the following things:
- A system capable of running the Go runtime.
- TLS certificate authorities on the disk.
- A functional IPv4/IPv6 network stack.
- A Tigris account, bucket, and access keypair (part of the core flow of this tool relies on Tigris' RenameObject call which is not part of the standard S3 API).
Prepare your .env file
objgit takes its configuration via flags, environment variables, and .env files in this order of precedence:
Here is a sample .env file:
# Use the AWS credential chain to load Tigris credentials
AWS_PROFILE=tigris
# If true, allow the execution of post-receive hooks
ALLOW_HOOKS=true
# Hook timeout in go time.Duration format
HOOK_TIMEOUT=60s
# If true, allow anonymous pushes
ALLOW_PUSH=true
# The Tigris bucket that all repos are stored in,
# as well as the SSH host key
BUCKET=xe-git-repos
# Per-protocol bindhosts
GIT_BIND=:9418
HTTP_BIND=:8080
SSH_BIND=:2222
# Pushes that unpack a packfile at the same time. This is what bounds
# memory under concurrent pushes: each one costs roughly 400 MiB of
# resident set for a large repository. 0 disables the limit.
MAX_CONCURRENT_PUSHES=4
# How long a push waits for a slot before it fails,
# in go time.Duration format
PUSH_QUEUE_TIMEOUT=2m
# Prometheus metrics
METRICS_BIND=:9090
# Logging detail level
SLOG_LEVEL=INFO
Run the program
go run ./cmd/objgitd
Push a repo
$ git push ssh://localhost:2222/xeiaso.net/objgit.git
Enumerating objects: 9, done.
Counting objects: 100% (9/9), done.
Delta compression using up to 32 threads
Compressing objects: 100% (9/9), done.
Writing objects: 100% (9/9), 2.80 KiB | 2.80 MiB/s, done.
Total 9 (delta 5), reused 0 (delta 0), pack-reused 0 (from 0)
remote: push to xeiaso.net/objgit.git refs/heads/main: a300ea49df20ad5dc82fc4dabb85fbd3261faed7 -> 3d889908eefd60d9a11605f077b7b4560aef8e74
remote: top-level contents:
remote: CLAUDE.md
remote: LICENSE
remote: README.md
remote: cmd
remote: docs
remote: go.mod
remote: go.sum
remote: internal
remote: go module: tangled.org/xeiaso.net/objgit
remote: manifest (/tmp/manifest.txt):
remote: ref refs/heads/main
remote: sha 3d889908eefd60d9a11605f077b7b4560aef8e74
remote: hook done
To ssh://localhost:2222/xeiaso.net/objgit.git
a300ea4..3d88990 main -> main
Deployment to production
TODO(Xe): re-evaluate performance-based life choices and write.
objgit 是一个实验项目：一个把代码仓库保存在对象存储（Tigris）里而不是本地磁盘上的 Git 服务器。作者称它只是一个概念验证，你目前大概还用不上。