[git: config gpg signing setup] Set up the automatic signing of each commit #git #shell

git_config_gpg_signing_setup.sh

# For setting up gpg not to require password upon each commit, do this (https://stackoverflow.com/questions/39494631/gpg-failed-to-sign-the-data-fatal-failed-to-write-commit-object-git-2-10-0)
brew upgrade gnupg  # This has a make step which takes a while
brew link --overwrite gnupg
brew install pinentry-mac
echo "pinentry-program /usr/local/bin/pinentry-mac" >> ~/.gnupg/gpg-agent.conf
killall gpg-agent
# to test it, use this
echo "test" | gpg --clearsign  # on linux it's gpg2 but brew stays as gpg
# to show the signature of a commit message
git log --show-signature -1