Skip to content
Branch: master
Find file Copy path
Find file Copy path
Fetching contributors…
Cannot retrieve contributors at this time
426 lines (323 sloc) 17.7 KB

Contributing Guide

How to help

We welcome your contributions and participation! If you aren't sure what to expect, here are some norms for our project so you feel more comfortable with how things will go.

Code of Conduct

The Porter community is governed by our Code of Conduct. This includes but isn't limited to: the porter and related mixin repositories, slack, interactions on social media, project meetings, conferences and meetups.

Find an issue

We have good first issues for new contributors and help wanted issues for our other contributors. When you have been contributing for a while, take a look at the "Backlog" column on our project board for high priority issues.

  • good first issue has extra information to help you make your first contribution.
  • help wanted are issues suitable for someone who isn't a core maintainer.
  • hmm 🛑🤔 issues should be avoided. They are not ready to be worked on yet because they are not finished being designed or we aren't sure if we want the feature, etc.

Maintainers will do our best regularly make new issues for you to solve and then help out as you work on them. 💖

We have a roadmap that will give you a good idea of the larger features that we are working on right now. That may help you decide what you would like to work on after you have tackled an issue or two to learn how to contribute to Porter. If you would like to contribute regularly to a larger issue on the roadmap, reach out to a maintainer on Slack.

Another great way to contribute is to create a mixin! You can start use the Porter Skeletor repository as a template to start, along with the Mixin Developer Guide.

When to open a pull request

It's OK to submit a PR directly for problems such as misspellings or other things where the motivation/problem is unambiguous.

If there isn't an issue for your PR, please make an issue first and explain the problem or motivation for the change you are proposing. When the solution isn't straightforward, for example "Implement missing command X", then also outline your proposed solution. Your PR will go smoother if the solution is agreed upon before you've spent a lot of time implementing it.

Since Porter is a CLI, the "solution" will usually look like this:

$ porter newcommand [OPTIONAL] [--someflag VALUE]
example output

How to test your pull request

We recommend running the following every time:

make verify build test-unit

If your test modified anything related to running a bundle, also run:

make test-integration

If you want to know all the targets that the CI runs, look at <build/> and <build/>.

How to get your pull request reviewed fast

🚧 If you aren't done yet, create a draft pull request or put WIP in the title so that reviewers wait for you to finish before commenting.

1️⃣ Limit your pull request to a single task. Don't tackle multiple unrelated things, especially refactoring. If you need large refactoring for your change, chat with a maintainer first, then do it in a separate PR first without any functionality changes.

🎳 Group related changes into commits will help us out a bunch when reviewing! For example, when you change dependencies and check in vendor, do that in a separate commit.

😅 Make requested changes in new commits. Please don't ammend or rebase commits that we have already reviewed. When your pull request is ready to merge, you can rebase your commits yourself, or we can squash when we merge. Just let us know what you are more comfortable with.

🚀 We encourage follow-on PRs and a reviewer may let you know in their comment if it is okay for their suggestion to be done in a follow-on PR. You can decide to make the change in the current PR immediately, or agree to tackle it in a reasonable amount of time in a subsequent pull request. If you can't get to it soon, please create an issue and link to it from the pull request comment so that we don't collectively forget.

The life of a pull request

  1. You create a draft or WIP pull request. Reviewers will ignore it mostly unless you mention someone and ask for help. Feel free to open one and use the pull request to see if the CI passes. Once you are ready for a review, remove the WIP or click "Ready for Review" and leave a comment that it's ready for review.

    If you create a regular pull request, a reviewer won't wait to review it.

  2. A reviewer will assign themselves to the pull request. If you don't see anyone assigned after 3 business days, you can leave a comment asking for a review, or ping in slack. Sometimes we have busy days, sick days, weekends and vacations, so a little patience is appreciated! 🙇‍♀️

  3. The reviewer will leave feedback.

    • nits: These are suggestions that you may decide incorporate into your pull request or not without further comment.
    • It can help to put a 👍 on comments that you have implemented so that you can keep track.
    • It is okay to clarify if you are being told to make a change or if it is a suggestion.
  4. After you have made the changes (in new commits please!), leave a comment. If 3 business days go by with no review, it is okay to bump.

  5. When a pull request has been approved, the reviewer will squash and merge your commits. If you prefer to rebase your own commits, at any time leave a comment on the pull request to let them know that.

At this point your changes are available in the canary release of Porter!

Follow-on PR

A follow-on PR is a pull request that finishes up suggestions from another pull request.

When the core of your changes are good, and it won't hurt to do more of the changes later, our preference is to merge early, and keep working on it in a subsequent. This allows us to start testing out the changes in our canary builds, and more importantly enables other developers to immediately start building their work on top of yours.

This helps us avoid pull requests to rely on other pull requests. It also avoids pull requests that last for months, and in general we try to not let "perfect be the enemy of the good". It's no fun to watch your work sit in purgatory, and it kills contributor momentum.

Contribution Ladder

Our ladder defines the roles and responsibilities on this project and how to participate with the goal of moving from a user to a maintainer. You will need to gain people's trust, demonstrate your competence and understanding, and meet the requirements of the role.

Community Members

Everyone is a community member! 😄 You've read this far so you are already ahead. 💯

Here are some ideas for how you can be more involved and participate in the community:

  • Comment on an issue that you’re interested in.
  • Submit a pull request to fix an issue.
  • Report a bug.
  • Share a bundle that you made and how it went.
  • Come chat with us in Slack.

They must follow our Code of Conduct.


Contributors have the following capabilities:

  • Have issues and pull requests assigned to them
  • Apply labels, milestones and projects
  • Mark issues as duplicates
  • Close, reopen, and assign issues and pull requests

They must agree to and follow this Contributing Guide.

How to become a contributor

To become a contributor, the maintainers of the project would like to see you:

  • Comment on issues with your experiences and opinions.
  • Add your comments and reviews on pull requests.
  • Contribute pull requests.
  • Open issues with bugs, experience reports, and questions.

Contributors and maintainers will do their best to watch for community members who may make good contributors. But don’t be shy, if you feel that this is you, please reach out to one or more of the contributors or maintainers.


Maintainers are members with extra capabilities:

  • Be a Code Owner and have reviews automatically requested.
  • Review pull requests.
  • Merge pull requests.

Maintainers also have additional responsibilities beyond just merging code:

  • Help foster a safe and welcoming environment for all project participants. This will include understanding and enforcing our Code of Conduct.
  • Organize and promote pull request reviews, e.g. prompting community members, contributors, and other maintainers to review.
  • Triage issues, e.g. adding labels, promoting discussions, finalizing decisions.
  • Help organize our development meetings, e.g. schedule, organize and execute agenda.

They must agree to and follow the Reviewing Guide.

How to become a maintainer

To become a maintainer, we would like you to see you be an effective contributor, and show that you can do some of the things maintainers do. Maintainers will do their best to regularly discuss promoting contributors. But don’t be shy, if you feel that this is you, please reach out to one or more of the maintainers.


Admins are maintainers with extra responsibilities:

  • Create new mixin repositories
  • Manage porter-* repositories
  • Manage porter-* teams

How to become an admin

It isn't expected that all maintainers will need or want to move up to admin. If you are a maintainer, and find yourself often asking an admin to do certain tasks for you and you would like to help out with administrative tasks, please reach out to one or more of the admins.

Developer Tasks

Initial setup

  1. Clone this repository with go get -u Porter relies on being in the GOPATH.
  2. Run make build install.

You now have canary builds of porter and all the mixins installed.

Makefile explained

Here are the most common Makefile tasks

  • build builds all binaries, porter and internal mixins.
  • build-porter-client just builds the porter client for your operating system. It does not build the porter-runtime binary. Useful when you just want to do a build and don't remember the proper way to call go build yourself.
  • build-porter builds both the porter client and runtime. It does not clean up generated files created by packr, so you usually want to also run clean-packr.
  • install-porter installs just porter from your bin into /usr/local/bin.
  • install-mixins installs just the mixins from your bin into /usr/local/bin. This is useful when you are working on the exec or kubernetes mixin.
  • install installs porter and the mixins from your bin into /usr/local/bin.
  • test-unit runs the unit tests.
  • test-integration runs the integration tests. This requires a kubernetes cluster setup with credentials located at ~/.kube/config. Expect this to take 10 minutes.
  • test-cli runs a small test of end-to-end tests that require a kubernetes cluster (same as test-integration).
  • docs-preview hosts the docs site. See Preview Documentation.
  • test runs all the tests.
  • clean-packr removes extra packr files that were a side-effect of the build. Normally this is run automatically but if you run into issues with packr and dep, run this command.
  • dep-ensure runs dep ensure for you while taking care of packr properly. Use this if your PRs are often failing on verify-vendor because of packr. This can be avoided entirely if you use make build-porter-client or make build.
  • verify-vendor cleans up packr generated files and verifies that dep's Gopkg.lock and vendor/ are up-to-date. Use this makefile target instead of running dep check manually.

Install mixins

When you run make build, the canary* build of mixins are automatically installed into your bin directory in the root of the repository. You can use porter mixin install NAME to install the latest released version of a mixin.

* canary = most recent successful build of master

Preview documentation

We use Hugo to build our documentation site, and it is hosted on Netlify.

  1. Install Hugo using brew install hugo, choco install hugo or go get -u
  2. Run make docs-preview to start Hugo. It will watch the file system for changes.
  3. Open http://localhost:1313 to preview the site.

If anyone is interested in contributing changes to our makefile to improve the authoring experience, such as doing this with Docker so that you don't need Hugo installed, it would be a welcome contribution! ❤️

Command Documentation

Our commands are documented at and that documentation is generated by our CLI. You should regenerate that documentation when you change any files in cmd/porter by running make docs-gen which is run every time you run make build.

Code structure and practices

Carolyn Van Slyck gave a talk about the design of Porter, Designing Command-Line Tools People Love that you may find helpful in understanding the why's behind its command grammar, package structure, use of dependency injection and testing strategies.

What is the general code layout?

  • cmd: go here to add a new command or flag to porter or one of the mixins in this repository
  • docs: our website
  • pkg
    • build: implements building the invocation image.
    • cache: handles the cache of bundles that have been pulled by commands like porter install --tag.
    • cnab: deals with the CNAB spec
      • cnab-to-oci: talking to an OCI registry.
      • config-adapter: converting porter.yaml to bundle.json.
      • extensions: extensions to the CNAB spec, at this point that's just dependencies.
      • provider: the CNAB runtime, i.e. porter install.
    • config: anything related to porter.yaml and ~/.porter.
    • context: essentially dependency injection that's needed throughout Porter, such as stdout, stderr, stdin, filesystem and command execution.
    • exec: the exec mixin
    • kubernetes: the kubernetes mixin
    • mixin: enums, functions and interfaces for the mixin framework.
      • feed: works with mixin atom feeds
      • provider: handles communicating with mixins
    • porter: the implementation of the porter commands. Every command in Porter has a corresponding function in here. packr
      • version: reusable library used by all the mixins for implementing their
    • templates: files that need to be compiled into the porter binary with version command.
  • scripts:
  • tests have Go-based integration tests.
  • vendor we use dep and check in vendor.


Print to the Out property for informational messages and send debug messages to the Err property.


fmt.Fprintln(p.Out, "Initiating battlestar protocol")
fmt.Fprintln(p.Err, "DEBUG: loading plans from r2d2...")

Most of the structs in Porter have an embedded struct. This has both Out and Err which represent stdout and stderr respectively. You should log to those instead of directly to stdout/stderr because that is how we capture output in our unit tests. That means use fmt.Fprint* instead of fmt.Print* so that you can pass in Out or Err.

Some of our commands are designed to be consumed by another tool and intermixing debug lines and the command output would make the resulting output unusable. For example, porter schema outputs a json schema and if log lines were sent to stdout as well, then the resulting json schema would be unparsable. This is why we send regular command output to Out and debug information to Err. It allows us to then run the command and see the debug output separately, like so porter schema --debug 2> err.log.


This section includes overviews of infrastructure Porter relies on, mostly intended for maintainers.

CDN Setup

See the CDN Setup Doc for details on the services Porter uses to host and distribute its release binaries.

You can’t perform that action at this time.