Referring to a previous post about developer experience, a re-occurring need when writing automation and/or glue code for software or infrastructure projects is to ensure all required software is installed on the execution machine. A lot of software exists to achieve this goal, e.g. NixOS or asdf, but sometimes a little bash can be enough to get the same results. Solidblocks Shell Software provides a small set of easy to use functions to install commonly used software for infrastructure projects.
The basic building blocks are the software_ensure_* functions like software_ensure_terraform which ensures that a certain software package is downloaded to a local .bin dir. Those software packages can then be prepended to the $PATH by the software_set_export_path function. For more details see Solidblocks Shell Software
The example below show a skeleton do-file leveraging this functionality
#!/usr/bin/env bash
set -eu -o pipefail
DIR="$(cd "$(dirname "$0")" ; pwd -P)"
# self contained function for initial solidblocks bootstrapping
function bootstrap_solidblocks() {
local default_dir="$(cd "$(dirname "$0")" ; pwd -P)"
local install_dir="${1:-${default_dir}/.solidblocks-shell}"
SOLIDBLOCKS_SHELL_VERSION="v0.0.68"
SOLIDBLOCKS_SHELL_CHECKSUM="1a7bb1d03b35e4cb94d825ec542d6f51c2c3cc1a3c387b0dea61eb4be32760a7"
local temp_file="$(mktemp)"
mkdir -p "${install_dir}"
curl -L "https://github.com/pellepelster/solidblocks/releases/download/${SOLIDBLOCKS_SHELL_VERSION}/solidblocks-shell-${SOLIDBLOCKS_SHELL_VERSION}.zip" > "${temp_file}"
echo "${SOLIDBLOCKS_SHELL_CHECKSUM} ${temp_file}" | sha256sum -c
cd "${install_dir}"
unzip -o -j "${temp_file}" -d "${install_dir}"
rm -f "${temp_file}"
}
# makes sure all lib functions are available
# and all bootstrapped software is on the $PATH
function ensure_environment() {
if [[ ! -d "${DIR}/.solidblocks-shell" ]]; then
echo "environment is not bootstrapped, please run ./do bootstrap first"
exit 1
fi
source "${DIR}/.solidblocks-shell/log.sh"
source "${DIR}/.solidblocks-shell/utils.sh"
source "${DIR}/.solidblocks-shell/pass.sh"
source "${DIR}/.solidblocks-shell/colors.sh"
source "${DIR}/.solidblocks-shell/software.sh"
software_set_export_path
}
# bootsrapping of solidblocks and all
# needed software for the project
function task_bootstrap() {
bootstrap_solidblocks
ensure_environment
software_ensure_terragrunt
software_ensure_terraform
}
# run the downloaded terraform version, ensure_environment ensures
# the downloaded versions takes precedence over any system binaries
function task_terraform {
terraform -version
}
#
function task_usage {
cat <<EOF
Usage: $0
bootstrap initialize the development environment
${FORMAT_BOLD}deployment${FORMAT_RESET}
terraform run terraform
EOF
exit 1
}
ARG=${1:-}
shift || true
# if we see the boostrap command assume solidshell is not yet initialized and skip environment setup
case "${ARG}" in
bootstrap) ;;
*) ensure_environment ;;
esac
case ${ARG} in
bootstrap) task_bootstrap "$@" ;;
terraform) task_terraform "$@" ;;
*) task_usage ;;
esac