Install a Terraform provider to a cache (tested on alpine Docker image)

install_terraform_provider.sh

#!/bin/sh -e

# Install a Terraform provider

OS=linux
ARCH=amd64

OPTS=`getopt -l dont-unzip,full-url:,group:,provider:,site:,url:,version: -- df:g:p:u:s:v: "$@"` || exit 1
eval set -- "$OPTS"

while true; do
    case "$1" in
        -d|--dont-unzip) unzip=no; shift;;
        -f|--full-url) full_url=$2; shift 2;;
        -g|--group) group=$2; shift 2;;
        -p|--provider) provider=$2; shift 2;;
        -u|--url) url=$2; shift 2;;
        -s|--site) site=$2; shift 2;;
        -v|--version) version=$2; shift 2;;
        --) shift; break;;
        *) echo "Unknown option: $1"; exit 2;;
    esac
done

if [ "$provider" = "" ]; then
    echo "--provider is required"
    exit 2
fi

if [ "$version" = "" ]; then
    echo "--version is required"
    exit 2
fi

provider_full="terraform-provider-${provider}"
if [ "$unzip" = "no" ]; then
    file="${provider_full}_${version}"
else
    file="${provider_full}_${version}_${OS}_${ARCH}.zip"
fi

[ "$group" = "" ] && group=hashicorp
[ "$site" = "" ] && site=registry.terraform.io
[ "$unzip" = "" ] && unzip=yes
[ "$url" = "" ] && url="https://releases.hashicorp.com/${provider_full}/${version}"
[ "$full_url" = "" ] && full_url="${url}/${file}"
cache_dir="/cache/${site}/${group}/${provider}/${version}/${OS}_${ARCH}"
file_full="${cache_dir}/${file}"

echo "**** Install terraform provider $provider v${version} to cache ****"

mkdir -p "$cache_dir"
if [ "$unzip" = "yes" ]; then
    wget -qO- "$full_url" | bsdtar -xvf- -C "$cache_dir"
else
    wget "$full_url" -O "$file_full"
    chmod +x "$file_full"
fi