Purge a file from Git history

If you've ever accidentally committed sensitive information to a Git repository, you know how important, and difficult, it is to remove it from history. While not the most straightforward of processes, Git provides a way to completely purge a file from history.

The git rm command allows you to remove a file from the working directory and the index. Using git rm --cached --ignore-unmatch <path> deletes the file from the index without removing it from the working directory. This allows you to remove a file from history without deleting it from your local machine.

Having figured out how to remove the file, we now need a way to rewrite the branch's history. Using git filter-branch --force --index-filter <command> --prune-empty --tag-name-filter cat -- --all, you can rewrite the branch's history, passing it the previous command. This command will remove the file from all commits in the repository.

Finally, you can use git push <remote> --force --all to force push the changes to the remote repository. This will overwrite the remote repository with the changes you made locally. Note that you need to have the necessary permissions to force push to the remote repository.

# Syntax:
#  git filter-branch --force --index-filter \
#    "git rm --cached --ignore-unmatch <path>" \
#    --prune-empty --tag-name-filter cat -- --all
#  git push <remote> --force --all

git filter-branch --force --index-filter \
  "git rm --cached --ignore-unmatch config/apiKeys.json" \
  --prune-empty --tag-name-filter cat -- --all
# Purges `config/apiKeys.json` from history

git push origin --force --all
# Force pushes the changes to the remote repository