github-backup

#!/usr/bin/env bash

# Check that the GitHub token is set
# See: https://github.com/settings/tokens
if [ -z ${GITHUB_TOKEN} ]; then
    echo "The 'GITHUB_TOKEN' environment variable must be set."
    exit
fi

# Check that all required binaries are installed
# Requires: https://github.com/antonmedv/xx
required_binaries=( 'which' 'git' 'curl' 'xx' 'xargs' )

for binary in ${required_binaries}; do
    if [ -z $(which ${binary}) ]; then
        echo "WARNING: '${binary}' is required for the backup process."
        exit
    fi
done

# Set default repository type (if environment is not set)
# Can be: all, owner (default), public, private, member
REPO_TYPE=${REPO_TYPE:-owner}

# Check how many pages are available from the API
repository_list=()
number_of_pages=$(curl -sI -H "Authorization: token ${GITHUB_TOKEN}" "https://api.github.com/user/repos?type=${REPO_TYPE}&page=1" | sed -nr 's/^Link:.*page=([0-9]+)>; rel="last".*/\1/p');

# Loop through and add lists from each page
echo "Found '${number_of_pages}' pages of repositories"
pageNumber=1
while [[ ${pageNumber} -le ${number_of_pages} ]]; do
    # Download the repository list from GitHubs API and filter a repo name list with 'fx'
    repository_list=(${repository_list[@]} $(curl -s -H "Authorization: token ${GITHUB_TOKEN}" "https://api.github.com/user/repos?type=${REPO_TYPE}&page=${pageNumber}" | xx 'this.forEach(function (c) { console.log(c.full_name) })' 2> /dev/null | xargs echo))
    pageNumber=$((${pageNumber} + 1))
done

# Loop through the repository list and clone or update
for repository in ${repository_list[@]}; do
    if [ -d "${repository}.git" ]; then
        # Pull any changes for a repository that already exists
        echo "- Updating repository: ${repository}"
        git -C "${repository}.git" pull &> /dev/null
    else
        # Clone repositories that don't already exist
        echo "- Cloning repository: ${repository}"
        git clone "git@github.com/${repository}" "${repository}.git" --bare &> /dev/null
    fi
done