CONTRIBUTING.md

Contributing

Thank you for your interest in contributing! The goal of ibc-rs is to provide a high quality, formally verified implementation of the IBC protocol.

All work on the code base should be motivated by a Github issue. Before opening a new issue, first do a search of open and closed issues to make sure that yours will not be a duplicate. If you would like to work on an issue which already exists, please indicate so by leaving a comment. If what you'd like to work on hasn't already been covered by an issue, then open a new one to get the process going.

The rest of this document outlines the best practices for contributing to this repository:

• Decision Making - process for agreeing to changes
• Issues - what makes a good issue
• Pull Requests - what makes a good pull request
• Forking - fork the repo to make pull requests
• Changelog - changes must be recorded in the changelog

Decision Making

When contributing to the project, the following process leads to the best chance of landing the changes in main.

All new contributions should start with a Github issue which captures the problem you're trying to solve. Starting off with an issue allows for early feedback. Once the issue is created, maintainers may request that more detailed documentation be written in the form of a Request for Comment (RFC) or an Architectural Decision Record (ADR).

Discussion at the RFC stage will build collective understanding of the dimensions of the problem and help structure conversations around trade-offs.

When the problem is well understood but the solution leads to large structural changes to the code base, these changes should be proposed in the form of an Architectural Decision Record (ADR). The ADR will help build consensus on an overall strategy to ensure that the code base maintains coherence in the larger context. If you are not comfortable with writing an ADR, you can open a regular issue and the maintainers will help you turn it into an ADR.

When the problem and the proposed solution are well understood, changes should start with a draft pull request against main. The draft status signals that work is underway. When the work is ready for feedback, hitting "Ready for Review" will signal to the maintainers to take a look.

Implementation trajectories should aim to proceed where possible as a series of smaller incremental changes, in the form of small PRs that can be merged quickly. This helps manage the load for reviewers and reduces the likelihood that PRs will sit open for long periods of time.

Each stage of the process is aimed at creating feedback cycles which align contributors and maintainers in order to ensure that:

• Contributors don’t waste their time implementing/proposing features which won’t land in main
• Maintainers have the necessary context in order to support and review contributions

Issues

We welcome bug reports, feature requests, and other contributions to our project. To open an issue, please follow these guidelines:

1. Search existing issues: Before opening a new issue, please search existing issues to ensure that is not a duplicates.

2. Provide a clear and descriptive title: This helps others understand the nature of the issue at a glance.

3. Provide detailed information: In the issue description, clearly state the purpose of the issue and follow the guidelines of the issue template

Note: A maintainer will take care of assigning the appropriate labels to your issue with the following convention:

• Objective-level (WHY): conveys the overarching purpose or objective of the issue by labels starting with "O" like O: security, O: new-feature, etc.

• Scope-level (WHICH): specifies the part of the system that the issue pertains to and labels starting with "S" like S: non-cosmos, S: no-std, etc.

• Admin-level (HOW) includes relevant administrative considerations on how best handling the issue and labels starting with "A" like A: help-wanted, A: critical, etc.

Pull Requests

If you have write access to the ibc-rs repo, you can directly branch off of main. This makes it easier for project maintainers to directly make changes to your branch should the need arise. Otherwise, check Forking section for instructions.

Branch names should be prefixed with the author's name followed by a short description of the feature, eg. name/feature-x.

Pull requests are made against main and are squash-merged into main.

PRs must:

• make reference to an issue outlining the context
• update any relevant documentation and include tests
• add a corresponding entry in the .changelog directory using unclog, see the Changelog section for more details.

Pull requests should aim to be small and self-contained to facilitate quick review and merging. Larger change sets should be broken up across multiple PRs. Commits should be concise but informative, and moderately clean. Commits will be squashed into a single commit for the PR with all the commit messages.

If the issue you worked on was tagged A: low-priority, we'll do our best to review it in a timely manner, but please expect longer wait times for a review in general. If a low priority issue is important to you, please leave a comment explaining why, and we will re-prioritize it!

Responsibilities of a PR Reviewer

If you're tagged as the reviewer of a PR, you are responsible for shepherding it through to completion. This includes fixing issues with the PR and taking the lead on decisions that need to be resolved in order to get the PR merged.

If you're tagged as a reviewer on a PR that affects a part of the code base that you are unfamiliar with, you can hand it off to someone (with their consent) who is more appropriate to shepherd the PR through to completion.

Forking

If you do not have write access to the repository, your contribution should be made through a fork on Github. Fork the repository, contribute to your fork (either in the main branch of the fork or in a separate branch), and then make a pull request back upstream.

When forking, add your fork's URL as a new git remote in your local copy of the repo. For instance, to create a fork and work on a branch of it:

• Create the fork on GitHub, using the fork button.
• cd to the original clone of the repo on your machine
• git remote rename origin upstream
• git remote add origin [email protected]:<location of fork>

Now origin refers to your fork and upstream refers to the original version. Now git push -u origin main to update the fork, and make pull requests against the original repo.

To pull in updates from the origin repo, run git fetch upstream followed by git rebase upstream/main (or whatever branch you're working in).

Changelog

Every non-trivial PR must update the CHANGELOG. This is accomplished indirectly by adding entries to the .changelog folder in unclog format using the unclog CLI tool. CHANGELOG.md will be built by whomever is responsible for performing a release just prior to release - this is to avoid changelog conflicts prior to releases.

Install unclog

cargo install unclog

Examples

Add a .changelog entry to signal that a bug was fixed, without mentioning any component.

unclog add -i update-unclog-instructions -s bug -n 1634 -m "Update CONTRIBUTING.md for latest version of unclog" --editor vim

Add a .changelog entry for the ibc crate.

unclog add -c ibc -s features --id a-new-feature --issue-no 1235 -m "msg about this new-feature" --editor vim

Preview unreleased changes

unclog build -u

The Changelog is not a record of what Pull Requests were merged; the commit history already shows that. The Changelog is a notice to users about how their expectations of the software should be modified. It is part of the UX of a release and is a critical user facing integration point. The Changelog must be clean, inviting, and readable, with concise, meaningful entries. Entries must be semantically meaningful to users. If a change takes multiple Pull Requests to complete, it should likely have only a single entry in the Changelog describing the net effect to the user. Instead of linking PRs directly, we instead prefer to log issues, which tend to be higher-level, hence more relevant for users.

When writing Changelog entries, ensure they are targeting users of the software, not fellow developers. Developers have much more context and care about more things than users do. Changelogs are for users.

Changelog structure is modeled after Tendermint Core and Hashicorp Consul. See those changelogs for examples.

We currently split changes for a given release between these four sections: Breaking Changes, Features, Improvements, Bug Fixes.

Entries in the changelog should initially be logged in the Unreleased section, which represents a "staging area" for accumulating all the changes throughout a release (see Pull Requests below). With each release, the entries then move from this section into their permanent place under a specific release number in Changelog.

Changelog entries should be formatted as follows:

- [pkg] Some description about the change ([#xxx](https://github.com/cosmos/ibc-rs/issues/xxx)) (optional @contributor)

Here, pkg is the part of the code that changed (typically a top-level crate, but could be <crate>/<module>), xxx is the issue number, and contributor is the author/s of the change.

It's also acceptable for xxx to refer to the relevant pull request, but issue numbers are preferred. Note this means issues (or pull-requests) should be opened first so the changelog can then be updated with the corresponding number.

Changelog entries should be ordered alphabetically according to the pkg, and numerically according to their issue/PR number.

Changes with multiple classifications should be doubly included (eg. a bug fix that is also a breaking change should be recorded under both).

Breaking changes are further subdivided according to the APIs/users they impact. Any change that effects multiple APIs/users should be recorded multiply - for instance, a change to some core protocol data structure might need to be reflected both as breaking the core protocol but also breaking any APIs where core data structures are exposed.