removeOldGitBranches.sh

#!/bin/sh
#############################################
## Bash script to cleanup git repositories ##
## Author: Rob Sonke                       ##
#############################################

# To execute this in all subdirs of the current dir:
# for d in ./*
# do
#   (cd $d && ~/Downloads/removeOldBranches.sh)
# done

# Settings
# how old should commits be in old branches?
WEEKS=6
# which branch will we use to check if it's merged into this?
BASEBRANCH=master

COLOR_OFF='\033[0m'
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'

##########################################
# DO NOT CHANGE ANYTHING BELOW THIS LINE #
##########################################
function getDateLimit {
  unamestr=$(uname)
  if [[ "$unamestr" == 'Darwin' ]]; then
    LIMIT=$(date -j -v-${WEEKS}w +%s)
  else
    LIMIT=$(date --date="$WEEKS weeks ago" +%s)
  fi
}

function filterByDate {
  while read branch date zone; do
    if [[ "$date" -le "$LIMIT" ]]; then
      echo $branch
    fi
  done
}

function skipBranches {
  sed 's/ *origin\///' | grep -v HEAD | grep -v master | grep -v develop \
  | sed -e 's~^\s\+~~' \
  | sed -e 's~refs/remotes/~~' \
  | sed -e 's~remotes/origin/~~' \
  | sed -e 's~^origin/~~'
}

function getRemoteBranches {
  git for-each-ref --sort=-committerdate refs/remotes --format="%(refname) %(committerdate:raw)"
}

##########################
# processing starts here #
##########################

# get a unix timestamp based on the number of weeks
getDateLimit

# Bring all up to date and make sure we work from the right branch
echo "Lets switch to $BASEBRANCH and make sure we're up to date."
git checkout $BASEBRANCH
git pull
git fetch --prune origin
echo

MERGED_BRANCHES=$(git branch -r --merged origin/$BASEBRANCH | skipBranches)

if [ -z "$MERGED_BRANCHES" ]
then
  echo "There are no old merged branches, let's move on to the unmerged branches.\n"
else
  echo "The following remote branches are fully merged into $BASEBRANCH and will be removed:"
  echo "$YELLOW$MERGED_BRANCHES$COLOR_OFF"
  read -p "\nAre you sure? (y/n)? "
  if [ "$REPLY" == "y" ]
  then
    # Remove remote fully merged branches
    echo "$MERGED_BRANCHES" | xargs -I% git push origin :%
    echo "${GREEN}Done${COLOR_OFF}\n"
  else
    echo "${RED}Cancelled${COLOR_OFF}\n"
  fi
fi

# Lets move on with unmerged branches but with only old commits
echo "--------------------------------------------------------------------\n"

# get all remote branches and filter them by our needs
OLD_BRANCHES=$(getRemoteBranches | filterByDate | skipBranches)

if [ -z "$OLD_BRANCHES" ]
then
  echo "There are no old unmerged branches.\n"
else
  echo "The following remote branches are NOT merged into $BASEBRANCH but contain only commits older then $WEEKS weeks and will be removed:"
  echo "$YELLOW$OLD_BRANCHES$COLOR_OFF"
  echo
  read -p "Are you sure? (y/n)? "
  if [ "$REPLY" == "y" ]
  then
    # Remove remote fully merged branches
    echo "$OLD_BRANCHES" | xargs -I% git push origin :%
    echo "${GREEN}Done${COLOR_OFF}\n"
  else
    echo "${RED}Cancelled${COLOR_OFF}\n"
  fi
fi

exit 0