smaller multistage builds

Dockerfile

@@ -1,9 +1,8 @@
-FROM eclipse-temurin:17-jdk-jammy as build
+FROM python:3.9.7-slim AS build
 
 RUN apt-get -y update && apt-get install -y apt-utils && \
     apt-get install -y -qq -o=Dpkg::Use-Pty=0 build-essential gfortran zlib1g-dev \
-    libhdf5-dev libcurl4-openssl-dev libboost-dev cmake wget python3 python3-pip && \
-    apt-get install -q -y --no-install-recommends curl dnsutils
+    libhdf5-dev libcurl4-openssl-dev libboost-dev cmake wget python3 python3-pip
 
 COPY . /vcellroot
 
@@ -27,12 +26,7 @@ RUN /usr/bin/cmake \
     make && \
     ctest -VV
 
-FROM eclipse-temurin:17-jdk-jammy as runtime
-
-RUN apt-get -y update && apt-get install -y apt-utils && \
-    apt-get install -y -qq -o=Dpkg::Use-Pty=0 build-essential gfortran zlib1g-dev \
-    libhdf5-dev libcurl4-openssl-dev libboost-dev cmake wget python3 python3-pip && \
-    apt-get install -q -y --no-install-recommends curl dnsutils
+FROM eclipse-temurin:17 AS jre-build
 
 # Create a custom Java runtime
 RUN $JAVA_HOME/bin/jlink \
@@ -43,12 +37,23 @@ RUN $JAVA_HOME/bin/jlink \
          --compress=2 \
          --output /javaruntime
 
-ENV JAVA_HOME=/javaruntime
+# Define base image and copy in jlink created minimal Java 17 environment
+FROM python:3.9.7-slim
+ENV JAVA_HOME=/opt/java/openjdk
 ENV PATH="${JAVA_HOME}/bin:${PATH}"
+COPY --from=jre-build /javaruntime $JAVA_HOME
 
+# now we have Java 17 and Python 3.9
 ENV DEBIAN_FRONTEND=noninteractive
 ENV LANG=en_US.UTF-8
 
+RUN apt-get -y update && \
+    apt-get install -y apt-utils && \
+    apt-get install -q -y --no-install-recommends curl dnsutils
+
+RUN apt-get install -y -qq -o=Dpkg::Use-Pty=0 gcc gfortran zlib1g \
+    libhdf5-103 libhdf5-cpp-103 libcurl4-openssl-dev zip
+
 COPY --from=build /vcellroot/build/bin /vcellbin
 
 WORKDIR /vcellbin