Contribution tips and tricks

Automatically signing every commit

The Contribution Guide explains the role the Developer Certificate of Origin plays in contributions to the CUE project. It also explains how git commit -s can be used to sign-off each commit. But:

• it's easy to forget the -s flag;
• it's not always possible/easy to fix up other tools that wrap the git commit step.

You can automate the sign-off step using a git hook. Run the following commands in the root of a git repository where you want to automatically sign-off each commit:

cat <<'EOD' > .git/hooks/prepare-commit-msg
#!/bin/sh

NAME=$(git config user.name)
EMAIL=$(git config user.email)

if [ -z "$NAME" ]; then
    echo "empty git config user.name"
    exit 1
fi

if [ -z "$EMAIL" ]; then
    echo "empty git config user.email"
    exit 1
fi

git interpret-trailers --if-exists doNothing --trailer \
    "Signed-off-by: $NAME <$EMAIL>" \
    --in-place "$1"
EOD
chmod +x .git/hooks/prepare-commit-msg

(if you already have a prepare-commit-msg hook, adapt it accordingly).