Permanently shred all traces of a file in git

git-destoryer.sh

#!/bin/bash
# @author madebycm (2025-05-31)

# File to be completely destroyed from Git history
TARGET_FILE="README.md"

echo "⚠️  WARNING: This will completely remove $TARGET_FILE from ALL Git history!"
echo "This action CANNOT be undone and will require force-pushing."
echo ""
read -p "Are you absolutely sure? Type 'YES' to continue: " confirmation

if [ "$confirmation" != "YES" ]; then
    echo "Aborted."
    exit 1
fi

echo ""
echo "Starting complete removal of $TARGET_FILE from Git history..."

# Create a backup tag before we start (just in case)
git tag backup-before-destroy-$(date +%Y%m%d-%H%M%S)

# Method 1: Using git filter-branch (traditional method)
echo "Step 1: Running git filter-branch..."
FILTER_BRANCH_SQUELCH_WARNING=1 git filter-branch --force --index-filter \
    "git rm --cached --ignore-unmatch $TARGET_FILE" \
    --prune-empty --tag-name-filter cat -- --all

# Method 2: Using BFG Repo-Cleaner alternative (git filter-repo)
# This is more thorough and faster
if command -v git-filter-repo &> /dev/null; then
    echo "Step 2: Running git-filter-repo for thorough removal..."
    git filter-repo --path $TARGET_FILE --invert-paths --force
else
    echo "Step 2: git-filter-repo not found, using additional filter-branch pass..."
    FILTER_BRANCH_SQUELCH_WARNING=1 git filter-branch --force --tree-filter \
        "rm -f $TARGET_FILE" \
        --prune-empty --tag-name-filter cat -- --all
fi

# Clean up refs
echo "Step 3: Cleaning up references..."
rm -rf .git/refs/original/
git reflog expire --expire=now --all
git gc --prune=now --aggressive

# Remove the file from working directory if it still exists
if [ -f "$TARGET_FILE" ]; then
    echo "Step 4: Removing $TARGET_FILE from working directory..."
    rm -f "$TARGET_FILE"
fi

echo ""
echo "✅ Local removal complete!"
echo ""
echo "⚠️  IMPORTANT: To remove from GitHub, you MUST now run:"
echo "    git push origin --force --all"
echo "    git push origin --force --tags"
echo ""
echo "⚠️  WARNING: This will rewrite history for all collaborators!"
echo ""
echo "After pushing, also consider:"
echo "1. Contact GitHub support to purge cached views"
echo "2. Ensure all collaborators delete and re-clone the repository"
echo "3. Check GitHub's 'Commits' page to verify removal"