git-next/README.md

# git-next

`git-next` is a combined server and command-line tool that enables trunk-based
development workflows where each commit must pass CI before being included in
the main branch.

## Features

- Enforce the requirement for each commit to pass the CI pipeline before being
  included in the main branch
- Provide a server component that manages the trunk-based development process
- Ensure a consistent, high-quality codebase by preventing untested changes
  from being merged

## Prerequisits

- Rust 1.76.0 or later
- pgk-config
- libssl-dev
- clang-16
- mold

## Installation

You can install `git-next` using Cargo:

```shell
cargo install git-next
```

## Configuration

- The repo has a `.git-next.toml` file in it's root. (N.B. see
  [#28](https://git.kemitix.net/kemitix/git-next/issues/28) for a planned
  alternative)
- CI checks should be configured to run when the `next` branch is `pushed`.
- The `dev` branch _must_ have the `main` branch as an ancestor.
- The `next` branch _must_ have the `main` branch as an ancestor.

## Behaviour

Development happens on the `dev` branch, where each commit is expected to
be able to pass the CI checks.

(Note: in the diagrams, mermaid isn't capable of showing `main` and `next` on
the same commit, so we show `next` as empty)

```mermaid
gitGraph
    commit
    commit

    branch next

    branch dev
    commit
    commit
    commit
```

When the `git-next` server sees that the `dev` branch is ahead of the `next`
branch, it will push the `next` branch fast-forward one commit along the `dev`
branch.

```mermaid
gitGraph
    commit
    commit

    branch next
    commit

    branch dev
    commit
    commit
```

It will then wait for the CI checks to pass for the newly updated `next` branch.
When the CI checks for the `next` branch pass, it will push the `main` branch
fast-forward to the `next` branch.

```mermaid
gitGraph
    commit
    commit
    commit

    branch next

    branch dev
    commit
    commit
```

If the CI checks should fail for the `next` branch, the developer should
**amend** that commit in the history of their `dev` branch.
They should then force-push their rebased `dev` branch.

```mermaid
gitGraph
    commit
    commit

    branch next
    commit

    checkout main

    branch dev
    commit

    commit
    commit
```

`git-next` will then detect that the `next` branch is no longer part of the
`dev` branch ancestory, and reset `next` back to `main`.
We then return to the top, where `git-next` sees that `dev` is ahead of `next`.

### Important

The `dev` branch _should_ have the `next` branch as an ancestor.

If the `git-next` server finds that this isn't the case, it will **force-push**
the `next` branch back to the same commit as the `main` branch.

In short, the `next` branch **belongs** to `git-next`.

## Getting Started

To use `git-next` for trunk-based development, follow these steps:

### Initialise the repo

You need to specify which branches you are using

To create the default config file, run this command in the root of your repo:

```shell
git next init
```

This will create a `.git-next.toml` file. [Default](./default.toml)

By default the expected branches are `main`, `next` and `dev`. Each of these
three branches _must_ exist in your repo.

### Initialise the server

The server uses the file `git-next-server.toml` for configuration.

The create the default config file, run this command:

```shell
git next server init
```

This will create a `git-next-server.toml` file. [Default](./server-default.toml)

Edit this file to your needs.

Specify the access token.

The `branch` parameter for the repo identies the branch where the
`.git-next.toml` file should be found.

### Run the server

In the directory with your `git-next-server.toml` file, run the command:

```shell
git next server start
```

## Contributing

Contributions to `git-next` are welcome! If you find a bug or have a feature
request, please
[create an issue](https://git.kemitix.net/kemitix/git-next/issues/new).
If you'd like to contribute code, feel free to submit a merge request.

Before you start committing, run the `just install-hooks` command to setup the
Git Hooks. ([Get Just](https://just.systems/man/en/chapter_3.html))

## Crate Dependency

The following diagram shows the dependency between the crates that make up `git-next`:

```mermaid
stateDiagram-v2:
    cli --> server
    cli --> git
    server --> config
    server --> git
    git --> config
```

## License

`git-next` is released under the [MIT License](./LICENSE).