git

pico/git-pr a self-hosted git collaboration server

We are trying to build the simplest git collaboration tool. The goal is to make self-hosting a git server as simple as running an SSH server -- all without sacrificing external collaborators time and energy.

git format-patch isn't the problem and pull requests aren't the solution.

We are combining mailing list and pull request workflows. In order to build the simplest collaboration tool, we needed something as simple as generating patches but the ease-of-use of pull requests.

The goal is not to create another code forge here. The goal is to create a very simple self-hosted git solution with the ability to collaborate with external contributors. All the code owner needs to setup a running git server:

• A single golang binary

All an external contributor needs is:

• An SSH keypair
• An SSH client

demo video

https://youtu.be/d28Dih-BBUw

the problem

Email is great as a decentralized system to send and receive changes (patchsets) to a git repo. However, onboarding a new user to a mailing list, properly setting up their email client, and then finally submitting the code contribution is enough to make many developers give up. Further, because we are leveraging the email protocol for collaboration, we are limited by its feature-set. For example, it is not possible to make edits to emails, everyone has a different client, those clients have different limitations around plain text email and downloading patches from it.

Github pull requests are easy to use, easy to edit, and easy to manage. The downside is it forces the user to be inside their website to perform reviews. For quick changes, this is great, but when you start reading code within a web browser, there are quite a few downsides. At a certain point, it makes more sense to review code inside your local development environment, IDE, etc. There are tools and plugins that allow users to review PRs inside their IDE, but it requires a herculean effort to make it usable.

Further, self-hosted solutions that mimic a pull request require a lot of infrastructure in order to manage it. A database, a web site connected to git, admin management, and services to manage it all. Another big point of friction: before an external user submits a code change, they first need to create an account and then login. This adds quite a bit of friction for a self-hosted solution, not only for an external contributor, but also for the code owner who has to provision the infra. Often times they also have to fork the repo within the code forge before submitting a PR. Then they never make a contribution ever again and a forked repo lingers. That seems silly.

introducing patch requests (PR)

Instead, we want to create a self-hosted git "server" that can handle sending and receiving patches without the cumbersome nature of setting up email or the limitations imposed by the email protocol. Further, we want the primary workflow to surround the local development environment. Github is bringing the IDE to the browser in order to support their workflow, we want to flip that idea on its head by making code reviews a first-class citizen inside your local development environment. This has an interesting side-effect: the owner is placed in a more collaborative role because they must create at least one patch to submit a review. They are already in their local editor, they are already creating a git commit and "pushing" it, so naturally it is easier to make code changes during the review itself.

We see this as a hybrid between the github workflow of a pull request and sending and receiving patches over email.

The basic idea is to leverage an SSH app to handle most of the interaction between contributor and owner of a project. Everything can be done completely within the terminal, in a way that is ergonomic and fully featured.

The web view is mostly for discovery.

Notifications would happen with RSS and all state mutations would result in the generation of static web assets so the web views can be hosted using a simple web file server.

format-patch workflow

# Owner hosts repo `test.git` using github

# Contributor clones repo
git clone git@github.com:picosh/test.git

# Contributor wants to make a change
# Contributor makes changes via commits
git add -A && git commit -m "fix: some bugs"

# Contributor runs:
git format-patch origin/main --stdout | ssh pr.pico.sh pr create test
# > Patch Request has been created (ID: 1)

# Owner can checkout patch:
ssh pr.pico.sh pr print 1 | git am -3
# Owner can comment (IN CODE), commit, then send another format-patch
# on top of the PR:
git format-patch origin/main --stdout | ssh pr.pico.sh pr add --review 1
# UI clearly marks patch as a review

# Contributor can checkout reviews
ssh pr.pico.sh pr print 1 | git am -3

# Owner can reject a pr:
ssh pr.pico.sh pr close 1

# Owner can accept a pr:
ssh pr.pico.sh pr accept 1

# Owner can prep PR for upstream:
git rebase -i origin/main

# Then push to upstream
git push origin main

# Done!

The fundamental collaboration tool here is format-patch. Whether you a submitting code changes or you are reviewing code changes, it all happens in code. Both contributor and owner are simply creating new commits and generating patches on top of each other. This obviates the need to have a web viewer where the reviewer can "comment" on a line of code block. There's no need, apply the contributor's patches, write comments or code changes, generate a new patch, send the patch to the git server as a "review." This flow also works the exact same if two users are collaborating on a set of changes.

This also solves the problem of sending multiple patchsets for the same code change. There's a single, central Patch Request where all changes and collaboration happens.

We could figure out a way to leverage git notes for reviews / comments, but honestly, that solution feels brutal and outside the comfort level of most git users. Just send reviews as code and write comments in the programming language you are using. It's the job of the contributor to "address" those comments and then remove them in subsequent patches. This is the forcing function to address all comments: the patch won't be merged if there are comment unaddressed in code; they cannot be ignored or else they will be upstreamed erroneously.

installation and setup

setup

Copy or create a git-pr.toml file inside ./data directory:

mkdir data
vim ./data/git-pr.toml
# configure file

docker

Run the ssh app image:

docker run -d -v ./data:/app/data ghcr.io/picosh/pico/git-ssh:latest

Run the web app image:

docker run -d -v ./data:/app/data ghcr.io/picosh/pico/git-web:latest

golang

Clone this repo and then build the go binaries:

make build

./build/ssh --config ./data/git-pr.toml

./build/web --config ./data/git-pr.toml

done!

Access the ssh app:

ssh -p 2222 localhost help

Access the web app:

curl localhost:3000

roadmap

[!IMPORTANT]
This project is being actively developed and we have not reached alpha status yet.

1. Better --cover-letter support
2. Support git range-diff workflow (in web view?)
3. More robust ACL rules (OR integrate with self-hosted git repos like gitolite)
4. Adapter to statically generate web view
5. Bulk modify PRs (rsync, sftp, sshfs)
6. Generate event log summary as a cover letter?
7. Support a diff workflow (convert git diff into mbox patch format)
8. Pubsub system to send events

ideas

1. Officially support git remotes?
2. PR build steps? (e.g. ci/cd, status checks, merge checks)
3. TUI?