Contribution Signing

We ask that contributions have code commits signed. This is important in order to prove, as best we can, the provenance of contributions.

The developer pushing a commit as part of a PR isn't necessarily the person who committed it originally, if the commit is not signed. This distorts the commit history and makes it hard to tell where code came from.

If a person "signs" a commit, they are free to use any name, specifically one not their own. Again, the commit history cannot be relied on to determine the origin of the code, if one developer is spoofing another. A malicious person could commit bad code (for instance a virus) and make it look like another developer created it.

The best solution, while not fool-proof, is to "securely sign" your commits. Such commits are digitally signed, with a GPG-key, and associated with your github account. It still isn't foolproof, because a malicious developer could create a bogus email and account, but it is more reliable than an unsigned or a "signed" commit.

If you don't sign your commits, we may accept your contribution, assuming it meets usefulness and contribution guidelines, but only if it isn't critical code and only after checking it carefully. If code performs an important role, we will insist that it be signed, and if it is critical code (however we interpret that), we will insist that your contributions be securely signed.

Read below to find out how to sign your commits :)

Basic Signing

You must sign your work, certifying that you either wrote the work or otherwise have the right to pass it on to an open source project.

Setup your commit message user name and email address. See Setting your email in Git to set these up globally or for a single repository.

git config --global user.email "john.public@example.com"
git config --global user.name "John Q Public"

Once in place, you merely have to use --signoff on your commits to your CodeIgniter fork.

git commit --signoff

or simply

git commit -s

This will sign your commits with the information setup in your git config, e.g.

Signed-off-by: John Q Public <john.public@example.com>

Your IDE may have a "Sign-Off" checkbox in the commit window, or even an option to automatically sign-off all commits you make. You could even alias git commit to use the -s flag so you don’t have to think about it.

By signing your work in this manner, you certify to a "Developer's Certificate of Origin". The current version of this certificate is in the Developer's Certificate of Origin 1.1 file in the root of this documentation.

Secure Signing

The "basic signing" described above cannot be verified, though it is a great start. To verify your commits, you will need to setup a GPG key, and attach it to your github account.

See the git tools page for directions on doing this. The complete story is part of Github help.

The basic steps are

Depending on your IDE, you may have to do your Git commits from your Git bash shell to use the -S option to force the secure signing.

Commit Messages

Regardless of how you sign a commit, commit messages are important too. They communicate the intent of a specific change, concisely. They make it easier to review code, and to find out why a change was made if the code history is examined later.

The audience for your commit messages will be the codebase maintainers, any code reviewers, and debuggers trying to figure out when a bug might have been introduced.

Do try to make your commit messages meaningful. .