CONTRIBUTING.md

Contributing

• Contributing
  • Overview
    • Responsibilities of the stewarding team
    • Ease of reviewing
    • Workflow
  • Project Board
  • Development Procedure
    • Testing
    • Pull Requests
    • Pull Request Templates
    • Requesting Reviews
    • Updating Documentation
  • Dependencies
  • Protobuf
  • Branching Model and Release
    • PR Targeting

Thank you for considering making contributions to Gaia! 🎉👍

Overview

Contributing to this repo can mean many things such as participating in discussion or proposing code changes. Following the processes outlined in this document will lead to the best chance of getting changes merged into the codebase.

Responsibilities of the stewarding team

Gaia has many stakeholders contributing and shaping the project. The Gaia stewarding team is composed of Informal Systems developers and is responsible for stewarding this project over time. This means that the stewarding team needs to understand the nature of, and agree to maintain, all of the changes that land on main or a backport branch. It may cost a few days/weeks' worth of time to submit a particular change, but maintaining that change over the years has a much higher cost that the stewarding team will bear.

Ease of reviewing

The fact that the stewarding team needs to be able to deeply understand the short-, medium- and long-term consequences of incoming changes means that changes need to be easy to review.

What makes a change easy to review, and more likely to land in an upcoming release?

1. Each pull request must do one thing. It must be very clear what that one thing is when looking at the pull request title, description, and linked issues. It must also be very clear what value it ultimately aims to deliver, and for which user(s). A single pull request that does multiple things, or without a clear articulation of the problem it attempts to solve, may be rejected immediately.

2. Each pull request must be manageable in size. Self-contained pull requests that are manageable in size may target main directly. Larger contributions though must be structured as a series of smaller pull requests each building upon the previous one, all ideally tracked in a tracking issue (i.e., an EPIC). These pull requests must target a long-lived feature branch. For details, see the development procedure guidelines. Poorly structured pull requests may be rejected immediately with a request to restructure them.

   Note: This does not necessarily apply to documentation-related changes or automatically generated code (e.g. generated from Protobuf definitions). But automatically generated code changes should occur within separate commits, so they are easily distinguishable from manual code changes.

Workflow

To ensure a smooth workflow for all contributors, a general procedure for contributing has been established.

1. Start by browsing existing issues and discussions. If you are looking for something interesting or if you have something in your mind, there is a chance it had been discussed.
   • Looking for a good place to start contributing? How about checking out some good first issues or bugs?
2. Determine whether a GitHub issue or discussion is more appropriate for your needs:
   1. If you want to propose something new that requires specification or an additional design, or you would like to change a process, start with a new discussion. With discussions, we can better handle the design process using discussion threads. A discussion usually leads to one or more issues.
   2. If the issue you want addressed is a specific proposal or a bug, then open a new issue.
   3. Review existing issues to find an issue you'd like to help with.
3. Participate in thoughtful discussion on that issue.
4. If you would like to contribute:
   1. Ensure that the proposal has been accepted.
   2. Ensure that nobody else has already begun working on this issue. If they have, make sure to contact them to collaborate.
   3. If nobody has been assigned for the issue and you would like to work on it, make a comment on the issue to inform the community of your intentions to begin work and please wait for an acknowledgement from the stewarding team.
5. To submit your work as a contribution to the repository, follow standard GitHub best practices. See development procedure guidelines below.

Note: For very small or trivial issues such as typos, you are not required to open an issue before submitting a PR. For complex problems or features, please make sure to open an issue and provide context and problem description. PRs opened before adequate design discussion has taken place in a GitHub issue have a high likelihood of being rejected without review.

Project Board

We use self-organizing principles to coordinate and collaborate across organizations in structured "EPICs" that focus on specific problem domains or architectural components of Gaia. For details, see the GitHub Project board.

The developers work in sprints, which are available in a GitHub Project.

Development Procedure

main must be stable, include only completed features and never fail make lint, make run-tests, or make build/install.

Depending on the scope of the work, we differentiate between self-contained pull requests and long-lived contributions (features).

Self-contained pull requests:

• Fork the repo (core developers must create a branch directly in the Gaia repo), branch from the HEAD of main, make some commits, and submit a PR to main.
• For developers who are core contributors and are working within the gaia repo, follow branch name conventions to ensure clear ownership of branches: {moniker}/{issue#}-branch-name.
• See Branching Model for more details.

Large contributions:

• Make sure that a feature branch is created in the repo. This will be created by the stewarding team after design discussions. The name convention for the feature branch must be feat/{issue#}-branch-name. Note that (similar to main) all feature branches have branch protection rules and they run the CI. Unlike main, feature branch may intermittently fail make lint, make run-tests, or make build/install.
• Fork the repo (core developers must create a branch directly in the Gaia repo), branch from the HEAD of the feature branch, make some commits, and submit a PR to the feature branch. All PRs targeting a feature branch should follow the same guidelines in this document.
• Once the feature is completed, submit a PR from the feature branch targeting main.

Be sure to run make format before every commit. The easiest way to do this is have your editor run it for you upon saving a file (most of the editors will do it anyway using a pre-configured setup of the programming language mode). A convenience git pre-commit hook that runs the formatters automatically before each commit is available in the contrib/githooks/ directory.

Note: Exceptions to the above guidelines are possible, but only after prior discussions with the stewarding team.

Testing

Tests can be executed by running make run-tests at the top level of the Gaia repository. For running the e2e tests, make sure to build the docker images by running make docker-build-all.

When testing a function under a variety of different inputs, we prefer to use table driven tests. Table driven test error messages should follow the following format <desc>, tc #<index>, i #<index>. <desc> is an optional short description of whats failing, tc is the index within the table of the testcase that is failing, and i is when there is a loop, exactly which iteration of the loop failed. The idea is you should be able to see the error message and figure out exactly what failed. Here is an example check:

<some table>
for tcIndex, tc := range cases {
<some code>
for i := 0; i < tc.numTxsToTest; i++ {
<some code>
require.Equal(t, expectedTx[:32], calculatedTx[:32],
"First 32 bytes of the txs differed. tc #%d, i #%d", tcIndex, i)

Pull Requests

Before submitting a pull request:

• synchronize your branch with the latest base branch (i.e., main or feature branch) and resolve any arising conflicts, e.g.,
  • either git fetch origin/main && git merge origin/main
  • or git fetch origin/main && git rebase -i origin/main
• run make lint, make run-tests, make build/install to ensure that all checks and tests pass.

Then:

1. If you have something to show, start with a Draft PR. It's good to have early validation of your work and we highly recommend this practice. A Draft PR also indicates to the community that the work is in progress. Draft PRs also help the stewarding team provide early feedback and ensure the work is in the right direction.
2. When the code is complete, change your PR from Draft to Ready for Review.
3. Go through the actions for each checkbox present in the PR template description. The PR actions are automatically provided for each new PR.
4. Be sure to include a relevant changelog entry in the Unreleased section of CHANGELOG.md (see file for log format). The entry should be on top of all others changes in the section.

PRs must have a category prefix that is based on the type of changes being made (for example, fix, feat, refactor, docs, and so on). The type must be included in the PR title as a prefix (for example, fix: <description>). This convention ensures that all changes that are committed to the base branch follow the Conventional Commits specification. Additionally, each PR should only address a single issue.

Pull requests are merged automatically using A:automerge action.

Note: When merging, GitHub will squash commits and rebase on top of the base branch.

Pull Request Templates

There are three PR templates. The default template contains links to the three templates. Please go the the Preview tab and select the appropriate sub-template:

• The production template is for types fix, feat, and refactor.
• The docs template is for documentation changes.
• The other template is for changes that do not affect production code.

Requesting Reviews

In order to accommodate the review process, the author of the PR must complete the author checklist (from the pull request template) to the best of their abilities before marking the PR as "Ready for Review". If you would like to receive early feedback on the PR, open the PR as a "Draft" and leave a comment in the PR indicating that you would like early feedback and tagging whoever you would like to receive feedback from.

Codeowners are marked automatically as the reviewers.

All PRs require at least two review approvals before they can be merged (one review might be acceptable in the case of minor changes to docs or other changes that do not affect production code). Each PR template has a reviewers checklist that must be completed before the PR can be merged. Each reviewer is responsible for all checked items unless they have indicated otherwise by leaving their handle next to specific items. In addition, use the following review explanations:

• LGTM without an explicit approval means that the changes look good, but you haven't thoroughly reviewed the reviewer checklist items.
• Approval means that you have completed some or all of the reviewer checklist items. If you only reviewed selected items, you must add your handle next to the items that you have reviewed. In addition, follow these guidelines:
  • You must also think through anything which ought to be included but is not
  • You must think through whether any added code could be partially combined (DRYed) with existing code
  • You must think through any potential security issues or incentive-compatibility flaws introduced by the changes
  • Naming must be consistent with conventions and the rest of the codebase
  • Code must live in a reasonable location, considering dependency structures (for example, not importing testing modules in production code, or including example code modules in production code).
  • If you approve the PR, you are responsible for any issues mentioned here and any issues that should have been addressed after thoroughly reviewing the reviewer checklist items in the pull request template.
• If you sat down with the PR submitter and did a pairing review, add this information in the Approval or your PR comments.
• If you are only making "surface level" reviews, submit notes as a comment review.

Updating Documentation

If you open a PR in Gaia, it is mandatory to update the relevant documentation in /docs.

Dependencies

We use Go Modules to manage dependency versions.

The main branch of every Cosmos repository should just build with go get, which means they should be kept up-to-date with their dependencies so we can get away with telling people they can just go get our software.

When dependencies in Gaia's go.mod are changed, it is generally accepted practice to delete go.sum and then run go mod tidy.

Since some dependencies are not under our control, a third party may break our build, in which case we can fall back on go mod tidy -v.

Protobuf

We use Protocol Buffers along with gogoproto to generate code for use in Gaia.

For deterministic behavior around Protobuf tooling, everything is containerized using Docker. Make sure to have Docker installed on your machine, or head to Docker's website to install it.

To generate the protobuf stubs, you can run make proto-gen.

Branching Model and Release

User-facing repos should adhere to the trunk based development branching model: https://trunkbaseddevelopment.com. User branches should start with a user name, example: {moniker}/{issue#}-branch-name.

Gaia follows semantic versioning, but with the some deviations to account for state-machine and API breaking changes. See RELEASE_PROCESS.md for details.

PR Targeting

Ensure that you base and target your PRs on either main or a feature branch.

All complete features and bug fixes must be targeted against main. Exception is for bug fixes which are only related to a released version. In that case, the related bug fix PRs must target against the release branch.

If needed, we will backport a commit from main to a release branch with appropriate consideration of versioning.