Provides the ability to remove the top 5 heavy references from projects (to be tested)

git-weight-loss.sh

#!/usr/bin/env bash

# description: This script provides the ability to remove the top 5 heavy references from projects
# author: dataday
# version: 0.1.0

# defaults
EXEC=$(realpath -L "${0#./}")
EXEC_BASE="${EXEC%/*}"
EXEC_NAME=$(basename "$EXEC")

# enable extended pattern matching features
# https://www.gnu.org/software/bash/manual/html_node/Pattern-Matching.html#Pattern-Matching
shopt -s extglob

function remove_file_reference() {
  local reference="$1"

  printf '%s\n' "Removing $reference"

  # remove the reference from all branches
  git filter-branch --index-filter $(git rm --cached --ignore-unmatch "$reference")

  # remove the local git backup
  rm -rf "$EXEC_BASE/.git/refs/original/"

  # set loose object expiry
  git reflog expire --all --expire='now'

  # check for remaining loose objects
  git fsck --full --unreachable

  # repack the git 'pack'
  git repack -A -d

  # remove reference from project
  git prune
}

#
# determines user action from prompt
function prompt() {
  local revision="$1"
  local reference="$2"

  # failed to determine file reference (not set or empty value)
  if [ -z ${reference+v} ]; then
    printf '%s\n' "Could not determine file reference: '$reference'"
    exit 1

  # determined file reference
  else
    # read user input to confirm reference removal
    read -p "Remove $reference ($revision)? (y|Y/n|N) " SELECTION </dev/tty;

    # pattern match user input from selection
    case "$SELECTION" in
      # remove reference
      @(y|Y) ) remove_file_reference "$reference" ;;
      # ignore reference
      @(n|N) ) printf '%s\n' "Ignoring $reference ($revision)" ;;
    esac
  fi
}

#
# inspect pack for top 5 heavy file references
git verify-pack -v .git/objects/pack/*.idx | sort -k 3 -n | tail -5 | while IFS= read -r line; do

  # assign asset revision hash
  revision=$(echo "$line" | cut -d' ' -f1)

  # assign file reference from revision hash
  reference=$(git rev-list --objects --all | grep "$revision")

  file_reference=$(echo "$reference" | cut -d' ' -f2)

  # call prompt to confirm file reference removal
  prompt "$revision" "$file_reference"
done

exit $?