collectd/docs/CONTRIBUTING.md

Contribution guidelines

Thanks for taking the time to contribute to the collectd project! This document tries to give some guidance to make the process of contributing to collectd as pleasant as possible.

Bug reports

Please report bugs as GitHub Issues. Try to answer the following questions:

• Which version of collectd are you using?
• Which operating system (distribution) are you using at which version?
• What is the expected behavior / output?
• What is the actual (observed) behavior / output?
• How can we reproduce the problem you're having?
• If collectd crashes, try to get a stack trace.

Please monitor your issue for a couple of days and reply to questions. To keep the project manageable, we have to do some housekeeping; meaning we will close issues that have become stale.

Code contributions

Please open a GitHub Pull Request (PR) to contribute bug fixes, features, cleanups, new plugins, … Patches sent to the mailing list have a tendency to fall through the cracks.

• Focus: Fix one thing in your PR. The smaller your change, the faster it will be reviewed and merged.
• Coding style: Please run clang-format -style=file -i $FILE after editing .c, .h and .proto files. If you don't want to install clang-format locally or your version produces a different result than the formatting check on Github, use contrib/format.sh to format files using the same web service used by our check.
• Documentation: New config options need to be documented in two places: the manpage (src/collectd.conf.pod) and the example config (src/collectd.conf.in). New plugins need to be added to the README file.
• Continuous integration: Once your PR is created, our continuous integration environment will try to build it on a number of platforms. If this reports a failure, please investigate and fix the problem. We will at best do a very casual review for failing PRs.
• Don't rebase: Rebasing your branch destroys the review history. If a review takes a long time, we may ask you to rebase on a more recent commit on the main branch, but please don't do that without being asked.
• types.db: One of the most common mistakes made by new contributors is the addition of (many) new types in the file src/types.db. The majority of usecases can be met with one of the existing entries. If you plan to add new entries to src/types.db, you should talk to us early in the design process.

Labels

PRs need to be categorized into one of three categories:

• Feature

  The code has new behavior. Performance improvements are typically considered features. These changes would typically go into a "feature release".

• Fix

  The code fixes a bug, regression, or otherwise unintended behavior. Documentation improvements are typically considered fixes. These changes would typically go into a "patch" release.

• Maintenance

  The change is not relevant for end users of collectd. This includes changes to the CI system, style changes, and refactorings. These changes are not documented in the release notes.

If you don't have access to modify labels yourself, you can trigger our bot to apply the right label for you by adding a prefix to the PR title:

• Feature: feat or perf.
• Fix: fix or docs.
• Maintenance: build, chore, ci, style, refactor, or test.

You are encouraged to use those prefixes together with the plugin you're modifying. A new feature in the CPU plugin would have the feat(cpu): prefix.

PRs should either introduce a new feature or fix a bug, not both. Such changes should be split into two PRs.

ChangeLog

Feature and Bug PRs need to have a one-line summary in the PR description. This information is used to automatically generate release notes. If you got here after creating the PR, you need to go to the PR description (shown as the first "comment" on the PR, made by yourself) and edit that description. Editing a PR will trigger the "ChangeLog" status to be updated.

For the summary itself, follow this style:

ChangeLog: Foo plugin: A specific issue people had has been fixed.

The summary must be on a line of its own, with a "ChangeLog:" prefix at the beginning of the line. To give the reader context for the information, the text should start with "${name} plugin" when making changes to a plugin, and "collectd" for the core daemon changes. Other common contexts are "Build system", and "Documentation". Use past tense and passive voice the for remainder, e.g. "a bug <describe impact> has been fixed", "a feature <describe impact> has been added".

Some PRs should be excluded from the release notes, e.g. changes to project internal documentation (such as this file). Those changes are not interesting for external users of the project and would reduce the value of the release notes. Maintainers may use the Maintenance label to mark those PRs.

Other resources

• Mailing list
• #collectd IRC channel on freenode.
• Old patch submission guideline