# Contributing Guidelines

The Kubernetes Helm project accepts contributions via GitHub pull requests. This document outlines the process to help get your contribution accepted.

## Reporting a Security Issue

Most of the time, when you find a bug in Helm, it should be reported
using [GitHub issues](https://github.com/helm/helm/issues). However, if
you are reporting a _security vulnerability_, please email a report to
[cncf-kubernetes-helm-security@lists.cncf.io](mailto:cncf-kubernetes-helm-security@lists.cncf.io). This will give
us a chance to try to fix the issue before it is exploited in the wild.

## Sign Your Work

The sign-off is a simple line at the end of the explanation for a commit. All 
commits needs to be signed. Your signature certifies that you wrote the patch or
otherwise have the right to contribute the material. The rules are pretty simple,
if you can certify the below (from [developercertificate.org](http://developercertificate.org/)):

```
Developer Certificate of Origin
Version 1.1

Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
1 Letterman Drive
Suite D4700
San Francisco, CA, 94129

Everyone is permitted to copy and distribute verbatim copies of this
license document, but changing it is not allowed.

Developer's Certificate of Origin 1.1

By making a contribution to this project, I certify that:

(a) The contribution was created in whole or in part by me and I
    have the right to submit it under the open source license
    indicated in the file; or

(b) The contribution is based upon previous work that, to the best
    of my knowledge, is covered under an appropriate open source
    license and I have the right under that license to submit that
    work with modifications, whether created in whole or in part
    by me, under the same open source license (unless I am
    permitted to submit under a different license), as indicated
    in the file; or

(c) The contribution was provided directly to me by some other
    person who certified (a), (b) or (c) and I have not modified
    it.

(d) I understand and agree that this project and the contribution
    are public and that a record of the contribution (including all
    personal information I submit with it, including my sign-off) is
    maintained indefinitely and may be redistributed consistent with
    this project or the open source license(s) involved.
```

Then you just add a line to every git commit message:

    Signed-off-by: Joe Smith <joe.smith@example.com>

Use your real name (sorry, no pseudonyms or anonymous contributions.)

If you set your `user.name` and `user.email` git configs, you can sign your
commit automatically with `git commit -s`.

Note: If your git config information is set properly then viewing the
 `git log` information for your commit will look something like this:

```
Author: Joe Smith <joe.smith@example.com>
Date:   Thu Feb 2 11:41:15 2018 -0800

    Update README

    Signed-off-by: Joe Smith <joe.smith@example.com>
```

Notice the `Author` and `Signed-off-by` lines match. If they don't
your PR will be rejected by the automated DCO check.

## Support Channels

Whether you are a user or contributor, official support channels include:

- [Issues](https://github.com/helm/helm/issues)
- Slack:
  - User: [#helm-users](https://kubernetes.slack.com/messages/C0NH30761/details/)
  - Contributor: [#helm-dev](https://kubernetes.slack.com/messages/C51E88VDG/)

Before opening a new issue or submitting a new pull request, it's helpful to search the project - it's likely that another user has already reported the issue you're facing, or it's a known issue that we're already aware of. It is also worth asking on the Slack channels.

## Milestones

We use milestones to track progress of releases. There are also 2 special milestones
used for helping us keep work organized: `Upcoming - Minor` and `Upcoming - Major`

`Upcoming - Minor` is used for keeping track of issues that aren't assigned to a specific
release but could easily be addressed in a minor release. `Upcoming - Major` keeps track
of issues that will need to be addressed in a major release. For example, if the current
version is `2.2.0` an issue/PR could fall in to one of 4 different active milestones:
`2.2.1`, `2.3.0`, `Upcoming - Minor`, or `Upcoming - Major`. If an issue pertains to a
specific upcoming bug or minor release, it would go into `2.2.1` or `2.3.0`. If the issue/PR
does not have a specific milestone yet, but it is likely that it will land in a `2.X` release,
it should go into `Upcoming - Minor`. If the issue/PR is a large functionality add or change
and/or it breaks compatibility, then it should be added to the `Upcoming - Major` milestone.
An issue that we are not sure we will be doing will not be added to any milestone.

A milestone (and hence release) is considered done when all outstanding issues/PRs have been closed or moved to another milestone.

## Semantic Versioning

Helm maintains a strong commitment to backward compatibility. All of our changes to protocols and formats are backward compatible from Helm 2.0 until Helm 3.0. No features, flags, or commands are removed or substantially modified (other than bug fixes).

We also try very hard to not change publicly accessible Go library definitions inside of the `pkg/` directory of our source code.

For a quick summary of our backward compatibility guidelines for releases between 2.0 and 3.0:

- Protobuf and gRPC changes MUST be backward compatible.
- Command line commands, flags, and arguments MUST be backward compatible
- File formats (such as Chart.yaml, repositories.yaml, and requirements.yaml) MUST be backward compatible
- Any chart that worked on a previous version of Helm MUST work on a new version of Helm (barring the cases where (a) Kubernetes itself changed, and (b) the chart worked because it exploited a bug)
- Chart repository functionality MUST be backward compatible
- Go libraries inside of `pkg/` SHOULD remain backward compatible (though code inside of `cmd/` may be changed from release to release without notice).

## Issues

Issues are used as the primary method for tracking anything to do with the Helm project.

### Issue Types

There are 4 types of issues (each with their own corresponding [label](#labels)):
- Question: These are support or functionality inquiries that we want to have a record of for
future reference. Generally these are questions that are too complex or large to store in the
Slack channel or have particular interest to the community as a whole. Depending on the discussion,
these can turn into "Feature" or "Bug" issues.
- Proposal: Used for items (like this one) that propose a new ideas or functionality that require
a larger community discussion. This allows for feedback from others in the community before a
feature is actually  developed. This is not needed for small additions. Final word on whether or
not a feature needs a proposal is up to the core maintainers. All issues that are proposals should
both have a label and an issue title of "Proposal: [the rest of the title]." A proposal can become
a "Feature" and does not require a milestone.
- Features: These track specific feature requests and ideas until they are complete. They can evolve
from a "Proposal" or can be submitted individually depending on the size.
- Bugs: These track bugs with the code or problems with the documentation (i.e. missing or incomplete)

### Issue Lifecycle

The issue lifecycle is mainly driven by the core maintainers, but is good information for those
contributing to Helm. All issue types follow the same general lifecycle. Differences are noted below.
1. Issue creation
2. Triage
    - The maintainer in charge of triaging will apply the proper labels for the issue. This
    includes labels for priority, type, and metadata (such as "starter"). The only issue
    priority we will be tracking is whether or not the issue is "critical." If additional
    levels are needed in the future, we will add them.
    - (If needed) Clean up the title to succinctly and clearly state the issue. Also ensure
    that proposals are prefaced with "Proposal".
    - Add the issue to the correct milestone. If any questions come up, don't worry about
    adding the issue to a milestone until the questions are answered.
    - We attempt to do this process at least once per work day.
3. Discussion
    - "Feature" and "Bug" issues should be connected to the PR that resolves it.
    - Whoever is working on a "Feature" or "Bug" issue (whether a maintainer or someone from
    the community), should either assign the issue to them self or make a comment in the issue
    saying that they are taking it.
    - "Proposal" and "Question" issues should stay open until resolved or if they have not been
    active for more than 30 days. This will help keep the issue queue to a manageable size and
    reduce noise. Should the issue need to stay open, the `keep open` label can be added.
4. Issue closure

## How to Contribute a Patch

1. Fork the repo, develop and test your code changes.
1. Use sign-off when making each of your commits (see [above](#sign-your-work)).
   If you forgot to sign some commits that are part of the contribution, you can ask [git to rewrite your commit history](https://git-scm.com/book/en/v2/Git-Tools-Rewriting-History).
1. Submit a pull request.

Coding conventions and standards are explained in the official developer docs:
[Developers Guide](docs/developers.md)

The next section contains more information on the workflow followed for Pull Requests.

## Pull Requests

Like any good open source project, we use Pull Requests (PRs) to track code changes.

### PR Lifecycle

1. PR creation
    - PRs are usually created to fix or else be a subset of other PRs that fix a particular issue.
    - We more than welcome PRs that are currently in progress. They are a great way to keep track of
    important work that is in-flight, but useful for others to see. If a PR is a work in progress,
    it **must** be prefaced with "WIP: [title]". Once the PR is ready for review, remove "WIP" from
    the title.
    - It is preferred, but not required, to have a PR tied to a specific issue. There can be
    circumstances where if it is a quick fix then an issue might be overkill. The details provided
    in the PR description would suffice in this case.
2. Triage
    - The maintainer in charge of triaging will apply the proper labels for the issue. This should
    include at least a size label, `bug` or `feature`, and `awaiting review` once all labels are applied.
    See the [Labels section](#labels) for full details on the definitions of labels.
    - Add the PR to the correct milestone. This should be the same as the issue the PR closes.
3. Assigning reviews
    - Once a review has the `awaiting review` label, maintainers will review them as schedule permits.
    The maintainer who takes the issue should self-request a review.
    - Any PR with the `size/large` label requires 2 review approvals from maintainers before it can be
    merged. Those with `size/medium` or `size/small` are per the judgement of the maintainers. 
4. Reviewing/Discussion
    - Once a maintainer begins reviewing a PR, they will remove the `awaiting review` label and add
    the `in progress` label so the person submitting knows that it is being worked on. This is
    especially helpful when the review may take awhile.
    - All reviews will be completed using Github review tool.
    - A "Comment" review should be used when there are questions about the code that should be
    answered, but that don't involve code changes. This type of review does not count as approval.
    - A "Changes Requested" review indicates that changes to the code need to be made before they will be
    merged.
    - Reviewers (maintainers) should update labels as needed (such as `needs rebase`).
    - Reviews are also welcome from others in the community, especially those who have encountered a bug or
    have requested a feature. In the code review, a message can be added, as well as `LGTM` if the PR is
    good to merge. It’s also possible to add comments to specific lines in a file, for giving context
    to the comment. 
5. PR owner should try to be responsive to comments by answering questions or changing code. If the
   owner is unsure of any comment, reach out to the person who added the comment in
   [#helm-dev](https://kubernetes.slack.com/messages/C51E88VDG/). Once all comments have been addressed,
   the PR is ready to be merged.
6. Merge or close
    - PRs should stay open until merged or if they have not been active for more than 30 days.
    This will help keep the PR queue to a manageable size and reduce noise. Should the PR need
    to stay open (like in the case of a WIP), the `keep open` label can be added.
    - If the owner of the PR is listed in `OWNERS`, that user **must** merge their own PRs or explicitly
    request another OWNER do that for them.
    - If the owner of a PR is _not_ listed in `OWNERS`, any maintainer may merge the PR once it is approved.

#### Documentation PRs

Documentation PRs will follow the same lifecycle as other PRs. They will also be labeled with the
`docs` label. For documentation, special attention will be paid to spelling, grammar, and clarity
(whereas those things don't matter *as* much for comments in code).

## The Triager

Each week, one of the core maintainers will serve as the designated "triager" starting after the
public standup meetings on Thursday. This person will be in charge triaging new PRs and issues
throughout the work week.

## Labels

The following tables define all label types used for Helm. It is split up by category.

### Common

| Label | Description |
| ----- | ----------- |
| `bug` | Marks an issue as a bug or a PR as a bugfix |
| `critical` | Marks an issue or PR as critical. This means that addressing the PR or issue is top priority and will be handled first by maintainers |
| `docs` | Indicates the issue or PR is a documentation change |
| `duplicate` | Indicates that the issue or PR is a duplicate of another |
| `feature` | Marks the issue as a feature request or a PR as a feature implementation |
| `keep open` | Denotes that the issue or PR should be kept open past 30 days of inactivity |
| `refactor` | Indicates that the issue is a code refactor and is not fixing a bug or adding additional functionality |

### Issue Specific

| Label | Description |
| ----- | ----------- |
| `help wanted` | This issue is one the core maintainers cannot get to right now and would appreciate help with |
| `proposal` | This issue is a proposal |
| `question/support` | This issue is a support request or question |
| `starter` | This issue is a good for someone new to contributing to Helm |
| `wont fix` | The issue has been discussed and will not be implemented (or accepted in the case of a proposal) |

### PR Specific

| Label | Description |
| ----- | ----------- |
| `awaiting review` | The PR has been triaged and is ready for someone to review |
| `breaking` | The PR has breaking changes (such as API changes) |
| `in progress` | Indicates that a maintainer is looking at the PR, even if no review has been posted yet |
| `needs pick` | Indicates that the PR needs to be picked into a feature branch (generally bugfix branches). Once it has been, the `picked` label should be applied and this one removed |
| `needs rebase` | A helper label used to indicate that the PR needs to be rebased before it can be merged. Used for easy filtering |
| `picked` | This PR has been picked into a feature branch |

#### Size labels

Size labels are used to indicate how "dangerous" a PR is. The guidelines below are used to assign the
labels, but ultimately this can be changed by the maintainers. For example, even if a PR only makes
30 lines of changes in 1 file, but it changes key functionality, it will likely be labeled as `size/large`
because it requires sign off from multiple people. Conversely, a PR that adds a small feature, but requires
another 150 lines of tests to cover all cases, could be labeled as `size/small` even though the number
lines is greater than defined below.

| Label | Description |
| ----- | ----------- |
| `size/small` | Anything less than or equal to 4 files and 150 lines. Only small amounts of manual testing may be required |
| `size/medium` | Anything greater than `size/small` and less than or equal to 8 files and 300 lines. Manual validation should be required. |
| `size/large` | Anything greater than `size/medium`. This should be thoroughly tested before merging and always requires 2 approvals. This also should be applied to anything that is a significant logic change. |
