Contributions should be made via pull requests. Pull requests will be reviewed by one or more maintainers and merged when acceptable.
The goal of the containerd project is to enable developers to build container
platforms on top of the APIs that the containerd projects expose.
The main entry point for a containerd consumer is the Go API. ctr
is a
development tool to quickly test features of containerd and is unsupported in
a production setting. The project has zero plans of supporting ctr
in the future.
When developing features inside the containerd codebase, changes should be focused towards building APIs to develop higher level functionality and not about adding a specific feature into the core codebase. Some features may benefit the container ecosystem, however, they may not be appropriate for a first class feature in containerd.
We ask that before contributing, please make the effort to coordinate with the maintainers of the project before submitting large or high impact PRs. This will prevent you from doing extra work that may or may not be merged.
PRs that are just submitted without any prior communication will likely be summarily closed.
While pull requests are the methodology for submitting changes to code, changes are much more likely to be accepted if they are accompanied by additional engineering work. While we don't define this explicitly, most of these goals are accomplished through communication of the design goals and subsequent solutions. Often times, it helps to first state the problem before presenting solutions.
Typically, the best methods of accomplishing this are to submit an issue, stating the problem. This issue can include a problem statement and a checklist with requirements. If solutions are proposed, alternatives should be listed and eliminated. Even if the criteria for elimination of a solution is frivolous, say so.
Larger changes typically work best with design documents, similar to those found
in design/
. These are focused on providing context to the design at the time
the feature was conceived and can inform future documentation contributions.
Make sure that new tests are added for bugs in order to catch regressions and tests with new features to exercise the new functionality that is added.
There are times for one line commit messages and this is not one of them. Commit messages should follow best practices, including explaining the context of the problem and how it was solved, including in caveats or follow up changes required. They should tell the story of the change and provide readers understanding of what led to it.
If you're lost about what this even means, please see How to Write a Git Commit Message for a start.
In practice, the best approach to maintaining a nice commit message is to
leverage a git add -p
and git commit --amend
to formulate a solid
changeset. This allows one to piece together a change, as information becomes
available.
If you squash a series of commits, don't just submit that. Re-write the commit message, as if the series of commits was a single stroke of brilliance.
That said, there is no requirement to have a single commit for a PR, as long as each commit tells the story. For example, if there is a feature that requires a package, it might make sense to have the package in a separate commit then have a subsequent commit that uses it.
If there are multiple authors who worked together on a PR that needs to be squashed,
please use Co-authored-by
to indicate each person who contributed to the PR. This
enables automated tools
and Github
to highlight everyone's role in the PR.
Remember, you're telling part of the story with the commit message. Don't make your chapter weird.
If you submit a contribution that adds a new file, please add the license
header. You can do so manually or use the ltag
tool. The ltag
templates
for filetypes are in the containerd/project
repository but the files you want
to tag are most likely in the main containerd project or any of the possible
subprojects. You can pass the path to the project repo root to ltag
but you
should run ltag
in the directory where you have new files.
$ go get github.com/kunalkushwaha/ltag
$ ltag -t {containerd/project rootdir}/script/validate/template
The above will add the appropriate license header to Go language source files, Makefiles, Dockerfiles, and shell scripts. New templates will need to be added if other kinds of files are added. Please consult the documentation at https://github.com/kunalkushwaha/ltag
The sign-off is a simple line at the end of the explanation for the patch. Your signature certifies that you wrote the patch or otherwise have the right to pass it on as an open-source patch. The rules are pretty simple: if you can certify the below (from developercertificate.org):
Developer Certificate of Origin
Version 1.1
Copyright (C) 2004, 2006 The Linux Foundation and its contributors.
660 York Street, Suite 102,
San Francisco, CA 94110 USA
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 <[email protected]>
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
.