Assuming a directory of repositories, ensure they are all up-to-date

update_repos.sh

#!/usr/bin/env bash
#
# Assuming a directory of repositories, ensure they are all up-to-date if:
#   1. HEAD is one of: gh-pages, master, or main
#   2. there are no local modifications
#
# For example:
#   cd git
#   ./update_repos.sh creativecommons
#
# This script is dedicated to the public domain under the CC0 1.0 Universal
# (CC0 1.0) Public Domain Dedication:
# https://creativecommons.org/publicdomain/zero/1.0/
#### SETUP ####################################################################

set -o errexit
set -o errtrace
set -o nounset

# shellcheck disable=SC2154
trap '_es=${?};
    printf "${0}: line ${LINENO}: \"${BASH_COMMAND}\"";
    printf " exited with a status of ${_es}\n";
    exit ${_es}' ERR

DIR_ORG="${1:?}"
DIR_ORG="${1%/}"
DIR_SCRIPT="$(cd -P -- "${0%/*}" && pwd -P)"
# https://en.wikipedia.org/wiki/ANSI_escape_code
E0="$(printf "\e[0m")"        # reset
E30="$(printf "\e[30m")"      # black foreground
E31="$(printf "\e[31m")"      # red foreground
E33="$(printf "\e[33m")"      # yellow foreground
E107="$(printf "\e[107m")"    # bright white background

#### FUNCTIONS ################################################################

check_dir_org() {
    if [[ ! -d "./${DIR_ORG}" ]]
    then
        error_exit "Invalid directory: '${DIR_ORG}'"
    fi
}

error_exit() {
    # Echo error message to stderr and exit with error
    echo -e "${E31}ERROR:${E0}${*}" 1>&2
    exit 1
}

print_header() {
    # Print 80 character wide black on white heading with time
    printf "${E30}${E107}# %-69s$(date '+%T')${E0}\n" "${@}"
}

print_warn() {
    # echo warn message to stdout
    echo -e "${E33}WARN:${E0}${*}"
}

process_repo() {
    local _dir_repo _repo_name
    _dir_repo="${1}"
    _repo_name="${_dir_repo#./"${DIR_ORG}"/}"
    print_header "${_dir_repo#./}"
    _head="$(git rev-parse --abbrev-ref HEAD)"
    if [[ "${_head}" != 'gh-pages' ]] \
        && [[ "${_head}" != 'master' ]] \
        && [[ "${_head}" != 'main' ]]
    then
        print_warn "(skipping) current branch (${_head}) is not main"
        echo
        return
    fi
    if [[ $(git status --porcelain --untracked-files=no | wc -l) -gt 0 ]]
    then
        print_warn "(skipping) repository contains modified files"
        echo
        return
    fi
    git pull
    echo
}

#### MAIN #####################################################################

cd "${DIR_SCRIPT}"

check_dir_org
for _dir_repo in ./"${DIR_ORG}"/*
do
    [[ -d "${_dir_repo}" ]] || continue
    [[ -d "${_dir_repo}/.git" ]] || continue
    pushd "${_dir_repo}" >/dev/null
    process_repo "${_dir_repo}"
    popd >/dev/null
done