Add stage with minimal image

Dockerfile

@@ -21,6 +21,23 @@ ENV ASCIIDOCTOR_VERSION=${asciidoctor_version} \
   ASCIIDOCTOR_BIBTEX_VERSION=${asciidoctor_bibtex_version}
 
 
+# # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
+# Minimal image with asciidoctor
+# # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
+
+FROM base AS main-minimal
+RUN echo "assemble minimal main image" # keep here to help --cache-from along
+
+LABEL MAINTAINERS="Guillaume Scheibel <[email protected]>, Damien DUPORTAL <[email protected]>"
+
+RUN apk add --no-cache \
+    ruby
+
+RUN gem install --no-document \
+    "asciidoctor:${ASCIIDOCTOR_VERSION}" \
+    "asciidoctor-pdf:${ASCIIDOCTOR_PDF_VERSION}"
+
+
 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
 # Haskell build for: erd
 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
@@ -50,13 +67,13 @@ RUN cabal v2-update \
 # Final image
 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
 
-FROM base AS main
-RUN echo "building main image" # keep here to help --cache-from along
+FROM main-minimal AS main
+RUN echo "assemble comprehensive main image" # keep here to help --cache-from along
 
 LABEL MAINTAINERS="Guillaume Scheibel <[email protected]>, Damien DUPORTAL <[email protected]>"
 
-# Installing package required for the runtime of
-# any of the asciidoctor-* functionnalities
+# Installing packagse required for the runtime of
+# any of the asciidoctor-* functionalities
 RUN apk add --no-cache \
     bash \
     curl \
@@ -71,7 +88,6 @@ RUN apk add --no-cache \
     python3 \
     py3-pillow \
     py3-setuptools \
-    ruby \
     ruby-bigdecimal \
     ruby-mathematical \
     ruby-rake \
@@ -81,20 +97,17 @@ RUN apk add --no-cache \
     unzip \
     which
 
-# Installing Ruby Gems needed in the image
-# including asciidoctor itself
+# Installing Ruby Gems for additional functionality
 RUN apk add --no-cache --virtual .rubymakedepends \
     build-base \
     libxml2-dev \
     ruby-dev \
   && gem install --no-document \
-    "asciidoctor:${ASCIIDOCTOR_VERSION}" \
     "asciidoctor-confluence:${ASCIIDOCTOR_CONFLUENCE_VERSION}" \
     "asciidoctor-diagram:${ASCIIDOCTOR_DIAGRAM_VERSION}" \
     "asciidoctor-epub3:${ASCIIDOCTOR_EPUB3_VERSION}" \
     "asciidoctor-mathematical:${ASCIIDOCTOR_MATHEMATICAL_VERSION}" \
     asciimath \
-    "asciidoctor-pdf:${ASCIIDOCTOR_PDF_VERSION}" \
     "asciidoctor-revealjs:${ASCIIDOCTOR_REVEALJS_VERSION}" \
     coderay \
     epubcheck-ruby:4.2.4.0 \
@@ -109,8 +122,8 @@ RUN apk add --no-cache --virtual .rubymakedepends \
     "asciidoctor-bibtex:${ASCIIDOCTOR_BIBTEX_VERSION}" \
   && apk del -r --no-cache .rubymakedepends
 
-# Installing Python dependencies for additional
-# functionnalities as diagrams or syntax highligthing
+# Installing Python dependencies for additional functionality
+# such as diagrams (blockdiag) or syntax highligthing
 RUN apk add --no-cache --virtual .pythonmakedepends \
     build-base \
     python3-dev \

Makefile

@@ -35,6 +35,13 @@ export DOCKER_IMAGE_NAME_TO_TEST \
 all: build test README.md
 
 build:
+	docker build \
+		--target main-minimal \
+		--tag="$(DOCKER_IMAGE_NAME_TO_TEST)-minimal" \
+		--build-arg BUILDKIT_INLINE_CACHE=1 \
+		--cache-from="$(DOCKER_IMAGE_NAME_TO_TEST)-minimal" \
+		--file=Dockerfile \
+		$(CURDIR)/
 	docker build \
 		--target build-haskell \
 		--tag="$(DOCKER_IMAGE_NAME_TO_TEST)-build-haskell" \
@@ -46,6 +53,7 @@ build:
 		--target main \
 		--tag="$(DOCKER_IMAGE_NAME_TO_TEST)" \
 		--build-arg BUILDKIT_INLINE_CACHE=1 \
+		--cache-from="$(DOCKER_IMAGE_NAME_TO_TEST)-minimal" \
 		--cache-from="$(DOCKER_IMAGE_NAME_TO_TEST)-build-haskell" \
 		--cache-from="$(DOCKER_IMAGE_NAME_TO_TEST)" \
 		--file=Dockerfile \