Get distro information from FROM image

Signed-off-by: Natalie Arellano <narellano@vmware.com>

base-images/alpine/base/Dockerfile

@@ -1,4 +1,4 @@
-FROM --platform=linux/amd64 alpine:3
+FROM alpine:3
 
 # Install packages that we want to make available at both build and run time
 RUN apk add --update --no-cache bash ca-certificates

base-images/build.sh

@@ -60,29 +60,30 @@ STACK_ID="${ID_PREFIX}.$(basename "${IMAGE_DIR}")"
 BASE_IMAGE=${REPO_PREFIX}:${TAG}
 RUN_IMAGE=${REPO_PREFIX}-run:${TAG}
 BUILD_IMAGE=${REPO_PREFIX}-build:${TAG}
-
-if [[ -d "${IMAGE_DIR}/base" ]]; then
-  docker build --platform=${PLATFORM} \
-  --build-arg "distro_name=${DISTRO_NAME}" \
-  --build-arg "distro_version=${DISTRO_VERSION}" \
-  --build-arg "stack_id=${STACK_ID}" \
-  -t "${BASE_IMAGE}" \
-  "${IMAGE_DIR}/base"
-fi
+FROM_IMAGE=$(head -n1 "${IMAGE_DIR}"/base/Dockerfile | cut -d' ' -f2)
 
 # Get target distro information
 if cmd /c ver; then
 DISTRO_NAME=""
-RAW_VERSION=$(docker run --rm "${BASE_IMAGE}" cmd /c ver)
+RAW_VERSION=$(docker run --rm "${FROM_IMAGE}" cmd /c ver)
 DISTRO_VERSION=$(echo "$RAW_VERSION" | head -n1 | sed 's/Microsoft Windows //' | sed 's/[][]//g' | cut -d' ' -f2)
 echo "DISTRO_VERSION: ${DISTRO_VERSION}"
 else
-DISTRO_NAME=$(docker run --rm "${BASE_IMAGE}" cat /etc/os-release | grep '^ID=' | cut -d'=' -f2)
+DISTRO_NAME=$(docker run --rm "${FROM_IMAGE}" cat /etc/os-release | grep '^ID=' | cut -d'=' -f2)
 echo "DISTRO_NAME: ${DISTRO_NAME}"
-DISTRO_VERSION=$(docker run --rm "${BASE_IMAGE}" cat /etc/os-release | grep '^VERSION_ID=' | cut -d'=' -f2)
+DISTRO_VERSION=$(docker run --rm "${FROM_IMAGE}" cat /etc/os-release | grep '^VERSION_ID=' | cut -d'=' -f2)
 echo "DISTRO_VERSION: ${DISTRO_VERSION}"
 fi
 
+if [[ -d "${IMAGE_DIR}/base" ]]; then
+  docker build --platform=${PLATFORM} \
+  --build-arg "distro_name=${DISTRO_NAME}" \
+  --build-arg "distro_version=${DISTRO_VERSION}" \
+  --build-arg "stack_id=${STACK_ID}" \
+  -t "${BASE_IMAGE}" \
+  "${IMAGE_DIR}/base"
+fi
+
 echo "BUILDING ${BUILD_IMAGE}..."
 docker build --platform=${PLATFORM} \
   --build-arg "base_image=${BASE_IMAGE}" \

base-images/jammy/base/Dockerfile

@@ -1,4 +1,4 @@
-FROM --platform=linux/amd64 ubuntu:jammy
+FROM ubuntu:jammy
 
 # Install packages that we want to make available at both build and run time
 RUN apt update && \