docs: theme, documenting intro and packer.

packer/build-image.sh

@@ -12,7 +12,8 @@ errmsg () {
 preflight () {
     case "${IMAGE_TYPE}" in
         ubuntu) PACKER_BUILD_FILE="boards/cm4-cluster-ubuntu-22.04.2.json" ;;
-        raspbian) PACKER_BUILD_FILE="boards/raspberry-pi/raspios-lite-arm.json" ;;
+        ## TODO(kyle): look into building a Raspbian version if needed.
+        # raspbian) PACKER_BUILD_FILE="boards/raspberry-pi/raspios-lite-arm.json" ;;
         custom)
             if [ -z "${PACKER_BUILD_FILE}" ]
             then
@@ -23,7 +24,7 @@ preflight () {
         *)
             errmsg "[!] invalid image type ${IMAGE_TYPE}."
             errmsg "[!] valid image types are"
-            errmsg "    - raspbian"
+            # errmsg "    - raspbian"
             errmsg "    - ubuntu"
             errmsg "    - custom path/to/board/file"
             exit 1

packer/install-packer.sh

@@ -9,9 +9,13 @@ PACKER_FILE=packer_${PACKER_VERSION}_linux_${ARCH}
 UPSTREAM="https://github.com/mkaczanowski/packer-builder-arm"
 UPGRADE="false"
 BUILD_DIR="$(pwd)/build"
+FORCE_DEPENDENCY_INSTALL="no"
 
 prep () {
-    sudo apt-get update && sudo apt-get -y install git unzip qemu-user-static e2fsprogs dosfstools 'bsdtar|libarchive-tools'
+    if [ -z "$(command -v git)" -o "${FORCE_DEPENDENCY_INSTALL}" = "yes" ]
+    then
+        sudo apt-get update && sudo apt-get -y install git unzip qemu-user-static e2fsprogs dosfstools libarchive-tools
+    fi
     mkdir -p ${BUILD_DIR}
     pushd ${BUILD_DIR}
 }