backup-github.sh

# Usage:
#
# 1. Get a personal access token with repo scope and place it in GITHUB_TOKEN
# 2. Run `backup-github /abs/path/to/dir` to backup repos to the given dir

backup-github () {
  local target="$1"
  local name=''
  local url=''
  local dir=''

  github-repos | while read -r name url ; do
    dir="$target/$name.git"

    if [[ -d "$dir" ]] ; then
      cd "$dir"
      git fetch --prune --verbose origin
      cd -
    else
      mkdir -p "$(dirname "$dir")"
      git clone --mirror "$url" "$dir"
    fi
  done
}

GITHUB_REPO_URL='https://api.github.com/user/repos'

github-repos () {
  local page=1
  local response=''

  while :; do
    response="$(curl -s "$GITHUB_REPO_URL?page=$page" -H "Authorization: Bearer $GITHUB_TOKEN")"

    if [[ $(jq 'length' <<<"$response") -eq 0 ]] ; then
      return
    else
      jq -r '.[] | .full_name + " " + .ssh_url' <<<"$response"
      let page=page+1
    fi
  done
}