Git hooks are used to run some arbitrary code before and after different git operations. The ones that begin with
pre- are used before the operation, and can be used to bail out of the operation.
post- hooks are run after an operation, but do not have built-in functionality revert the operation itself.
We're going to use
pre-commit hooks to make sure we never accidentally push to an un-protected master branch. It is only going to affect our own local copies of the repositories. You will need git 2.9+ (June 2016). The script we will create will ask you if you want to commit/push to master, so you will still be able to if that's your intention.
Make a place to house your global hooks.
mkdir -p ~/.githooks # this name/location doesn't matter
Create a file called
pre-push in this directory.
#!/bin/bash protected_branch='master' current_branch=$(git symbolic-ref HEAD | sed -e 's,.*/\(.*\),\1,') if [ $protected_branch = $current_branch ] then read -p "You're about to push master, is this what you intended? [y|n] " -n 1 -r < /dev/tty echo if echo $REPLY | grep -E '^[Yy]$' > /dev/null then exit 0 # push will execute fi exit 1 # push will not execute else exit 0 # push will execute fi
We should also make a
pre-commit hook. To do this, copy the
pre-push file to a new file
pre-commit, and change to the prompt to say "commit" instead of "push".
pre-commit is arguably more important and sort of renders
pre-push useless. You can never be too careful though.
Set the files to be executable:
chmod a+x ~/.githooks/pre-push chmod a+x ~/.githooks/pre-commit
Set your global hooks folder to be recognized by git:
git config --global core.hooksPath ~/.githooks
Now if you try to commit or push to master on any repo on your machine, the hook will ask you to make sure you want to do that.
If you want to apply this on a per project basis, then you will need to add the
pre-commit files to the project's
.git/hooks folder instead of a global hooks folder.