full build test for branched version of mod

Dockerfile

@@ -1,53 +1,37 @@
-FROM lsiobase/ubuntu:bionic
+## Buildstage ##
+FROM lsiobase/ubuntu:bionic as buildstage
 
-# set version label
 ARG BUILD_DATE
 ARG VERSION
-ARG CALIBREWEB_RELEASE
+ARG CALIBRE_RELEASE
 LABEL build_version="Linuxserver.io version:- ${VERSION} Build-date:- ${BUILD_DATE}"
 LABEL maintainer="chbmb"
 
 RUN \
- echo "**** install build packages ****" && \
+ echo "**** Install packages ****" && \
  apt-get update && \
  apt-get install -y \
-	git \
-	python-pip && \
- echo "**** install runtime packages ****" && \
- apt-get install -y \
-	imagemagick \
-	python-minimal && \
- echo "**** install calibre-web ****" && \
- if [ -z ${CALIBREWEB_RELEASE+x} ]; then \
-	CALIBREWEB_RELEASE=$(curl -sX GET "https://api.github.com/repos/janeczku/calibre-web/releases/latest" \
+	xz-utils && \
+ echo "**** Fetch calibre bin ****" && \
+ if [ -z ${CALIBRE_RELEASE+x} ]; then \
+	CALIBRE_RELEASE=$(curl -sX GET "https://api.github.com/repos/kovidgoyal/calibre/releases/latest" \
 	| awk '/tag_name/{print $4;exit}' FS='[""]'); \
  fi && \
- curl -o \
- /tmp/calibre-web.tar.gz -L \
-	https://github.com/janeczku/calibre-web/archive/${CALIBREWEB_RELEASE}.tar.gz && \
+ CALIBRE_RELEASE=$(echo "${CALIBRE_RELEASE}" | sed 's/^v//g' ) && \ 
  mkdir -p \
-	/app/calibre-web && \
+    /root-layer/app/calibre && \
+ curl -o \
+	/tmp/calibre.txz -L \
+	"https://github.com/kovidgoyal/calibre/releases/download/v${CALIBRE_RELEASE}/calibre-${CALIBRE_RELEASE}-x86_64.txz" && \
  tar xf \
- /tmp/calibre-web.tar.gz -C \
-	/app/calibre-web --strip-components=1 && \
- cd /app/calibre-web && \
- pip install --no-cache-dir -U -r \
-	requirements.txt && \
- pip install --no-cache-dir -U -r \
-	optional-requirements.txt && \
- echo "**** cleanup ****" && \
- apt-get -y purge \
-	git \
-	python-pip && \
- apt-get -y autoremove && \
- rm -rf \
-	/tmp/* \
-	/var/lib/apt/lists/* \
-	/var/tmp/*
-
-# add local files
-COPY root/ /
+	/tmp/calibre.txz \
+	-C /root-layer/app/calibre
+
+# copy local files
+COPY root/ /root-layer/
+
+## Single layer deployed image ##
+FROM scratch
 
-# ports and volumes
-EXPOSE 8083
-VOLUME /books /config
+# Add files from buildstage
+COPY --from=buildstage /root-layer/ /