Refactor script to support version and install path

Author: jgarber623-cargosense

src/shellcheck/README.md

@@ -10,6 +10,15 @@ Install [ShellCheck](https://www.shellcheck.net), a static analysis tool for she
 }
 ```
 
+## Options
+
+| Option ID     | Description                                  | Type   | Default Value    |
+|:--------------|:---------------------------------------------|:-------|:-----------------|
+| `version`     | The ShellCheck version to install.           | string | `os-provided`    |
+| `installPath` | The path where ShellCheck will be installed. | string | `/usr/local/bin` |
+
 ## OS Support
 
 This Feature should work on recent versions of Debian/Ubuntu and Linux distributions using the [apt](https://wiki.debian.org/AptCLI) management tool.
+
+`bash` is required to execute the `install.sh` script.

src/shellcheck/devcontainer-feature.json

@@ -3,8 +3,18 @@
     "id": "shellcheck",
     "version": "1.0.0",
     "description": "Install ShellCheck, a static analysis tool for shell scripts.",
+    "options": {
+      "version": {
+        "type": "string",
+        "proposals": [
+          "latest",
+          "os-provided"
+        ],
+        "default": "os-provided",
+        "description": "Select or enter a ShellCheck version."
+      }
+    },
     "installsAfter": [
       "ghcr.io/devcontainers/features/common-utils"
     ]
   }
-  

src/shellcheck/install.sh

@@ -1,11 +1,52 @@
-#!/usr/bin/env sh
+#!/usr/bin/env bash
 
 set -e
 
+SHELLCHECK_VERSION="${VERSION:-"os-provided"}"
+INSTALL_PATH="${INSTALLPATH:-"/usr/local/bin"}"
+
 if [ "$(id -u)" -ne 0 ]; then
   printf 'Script must be run as root. Use sudo, su, or add "USER root" to your Dockerfile before running this script.'
   exit 1
 fi
 
-apt update --yes
-apt install --no-install-recommends --yes shellcheck
+
+if [ "${SHELLCHECK_VERSION}" = "os-provided" ]; then
+  apt update --yes
+  apt install --no-install-recommends --yes shellcheck
+
+  exit 0
+fi
+
+curl_installed=""
+
+if ! type curl >/dev/null 2>&1; then
+  apt update --yes
+  apt install --no-install-recommends --yes curl ca-certificates
+
+  curl_installed="true"
+fi
+
+if [ "${SHELLCHECK_VERSION}" = "latest" ]; then
+  SHELLCHECK_VERSION=$(curl -s --head https://github.com/koalaman/shellcheck/releases/latest | sed -nr 's/location:.*\/v(.+)/\1/ip' | tr -d '\r')
+fi
+
+machine="$(uname -m)"
+case "${machine}" in
+  aarch64) arch="aarch64" ;;
+  arm*) arch="armv6" ;;
+  x86_64) arch="x86_64" ;;
+  *)
+    echo "Could not determine arch from machine hardware name '${machine}'" >&2
+    exit 1
+  ;;
+esac
+
+# https://github.com/koalaman/shellcheck/releases/download/v0.9.0/shellcheck-v0.9.0.linux.aarch64.tar.xz
+url="https://github.com/koalaman/shellcheck/releases/download/v${SHELLCHECK_VERSION}/shellcheck-v${SHELLCHECK_VERSION}.linux.${arch}.tar.xz"
+
+curl -sSL "${url}" | tar --strip-components=1 -Jxvf - -C "${INSTALL_PATH}" "shellcheck-v${SHELLCHECK_VERSION}/shellcheck"
+
+if [ -n "${curl_installed}" ]; then
+  apt purge curl --autoremove --yes
+fi