Git pre-push hook to prevent force-pushing or deleting a special branch (e.g. master)

pre-push.sh

#!/bin/bash

# Requires git 1.8.2 or newer
# Prevents force-pushing or deleting a special branch (e.g. master).
# Based on: https://gist.github.com/pixelhandler/5718585 and https://gist.github.com/stefansundin/d465f1e331fc5c632088

# Install:
# cd path/to/git/repo
# curl -fL -o .git/hooks/pre-push https://gist.githubusercontent.com/lyoshenka/158cfff41d09e1dcf029/raw/pre-push.sh
# chmod +x .git/hooks/pre-push


PROTECTED_BRANCH='master'

CURRENT_BRANCH=$(git rev-parse --abbrev-ref HEAD)

PUSH_COMMAND=$(ps -ocommand= -p $PPID)

IS_DESTRUCTIVE='\-\-force|\-\-delete|\-f'

WILL_DELETE_PROTECTED_BRANCH=" :$PROTECTED_BRANCH"

if [[ $PUSH_COMMAND =~ $IS_DESTRUCTIVE ]] && ( [ $CURRENT_BRANCH = $PROTECTED_BRANCH ] || [[ $PUSH_COMMAND =~ $PROTECTED_BRANCH ]] ) ||
   [[ $PUSH_COMMAND =~ $WILL_DELETE_PROTECTED_BRANCH ]]; then
  echo -e "\n[PRE-PUSH HOOK ERROR] Do not force-push or delete the \"$PROTECTED_BRANCH\" branch!\n"
  # you can skip this check with --no-verify
  exit 1
fi

exit 0

z-pre-push-installer.sh

#!/bin/sh
# This script will install a Git pre-push hook that prevents force pushing the master branch.
# Install in current Git repo:
# curl -fL https://gist.githubusercontent.com/lyoshenka/158cfff41d09e1dcf029/raw/z-pre-push-installer.sh | bash

# Uninstall:
# rm .git/hooks/pre-push
# in each repository that you've added this to.

GITROOT=`git rev-parse --show-toplevel 2> /dev/null`

echo
echo

if [ "$GITROOT" == "" ]; then
	echo This does not appear to be a git repo.
	exit 1
fi

if [ -f "$GITROOT/.git/hooks/pre-push" ]; then
	echo There is already a pre-push hook installed. Delete it first.
	echo
	echo "    rm '$GITROOT/.git/hooks/pre-push'"
	echo
	exit 2
fi

echo Downloading pre-push hook from https://gist.github.com/lyoshenka/158cfff41d09e1dcf029
echo

curl -fL -o "$GITROOT/.git/hooks/pre-push" "https://gist.githubusercontent.com/lyoshenka/158cfff41d09e1dcf029/raw/pre-push.sh"
if [ ! -f "$GITROOT/.git/hooks/pre-push" ]; then
	echo Error downloading pre-push script!
	exit 3
fi

chmod +x "$GITROOT/.git/hooks/pre-push"

echo "You're all set! Happy hacking!"

exit 0