Dockerfiles improvements

- investigates Docker image caching not fully leveraged, refs #160
- tries to keep image light in size, refs #161

Makefile

@@ -60,11 +60,11 @@ endif
 
 system_dependencies_linux:
 ifeq ($(OS), Ubuntu)
-	sudo apt update -qq > /dev/null && sudo apt install --yes --no-install-recommends $(SYSTEM_DEPENDENCIES_LINUX)
+	sudo apt update -qq > /dev/null && sudo apt -qq install --yes --no-install-recommends $(SYSTEM_DEPENDENCIES_LINUX)
 endif
 system_dependencies_android:
 ifeq ($(OS), Ubuntu)
-	sudo apt update -qq > /dev/null && sudo apt install --yes --no-install-recommends $(SYSTEM_DEPENDENCIES_ANDROID)
+	sudo apt update -qq > /dev/null && sudo apt -qq install --yes --no-install-recommends $(SYSTEM_DEPENDENCIES_ANDROID)
 endif
 
 

dockerfiles/Dockerfile-android

@@ -11,7 +11,7 @@ FROM ubuntu:18.04
 
 ENV USER="user"
 ENV HOME_DIR="/home/${USER}"
-ENV WORK_DIR="${HOME_DIR}" \
+ENV WORK_DIR="${HOME_DIR}/app" \
     PATH="${HOME_DIR}/.local/bin:${PATH}"
 ENV DOCKERFILES_VERSION="develop" \
     DOCKERFILES_URL="https://raw.githubusercontent.com/AndreMiras/dockerfiles"
@@ -21,7 +21,8 @@ ENV MAKEFILES_URL="${DOCKERFILES_URL}/${DOCKERFILES_VERSION}/buildozer_android"
 # configure locale
 RUN apt update -qq > /dev/null && apt install -qq --yes --no-install-recommends \
     locales && \
-    locale-gen en_US.UTF-8
+    locale-gen en_US.UTF-8 && \
+    rm -rf /var/lib/apt/lists/*
 ENV LANG="en_US.UTF-8" \
     LANGUAGE="en_US.UTF-8" \
     LC_ALL="en_US.UTF-8"
@@ -32,25 +33,27 @@ ENV LANG="en_US.UTF-8" \
 RUN apt update -qq > /dev/null && apt install -qq --yes --no-install-recommends \
     lsb-release \
     make \
-    sudo
+    sudo && \
+    rm -rf /var/lib/apt/lists/*
 
-# prepare non root env
-RUN useradd --create-home --shell /bin/bash ${USER}
-# with sudo access and no password
-RUN usermod -append --groups sudo ${USER}
-RUN echo "%sudo ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
+# prepare non root env, with sudo access and no password
+RUN useradd --create-home --home-dir ${HOME_DIR} --shell /bin/bash ${USER} && \
+    usermod -append --groups sudo ${USER} && \
+    echo "%sudo ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
 
 USER ${USER}
 WORKDIR ${WORK_DIR}
 
-COPY Makefile ${WORK_DIR}
-RUN sudo make system_dependencies_android
+COPY Makefile /tmp/Makefile
+RUN sudo make --file /tmp/Makefile system_dependencies_android && \
+    sudo rm /tmp/Makefile && \
+    sudo rm -rf /var/lib/apt/lists/*
 
-# install buildozer and dependencies
-RUN curl --location --progress-bar ${MAKEFILES_URL}/buildozer.mk --output buildozer.mk
-RUN make -f buildozer.mk
-# enforces buildozer master (d483847) until next release
-RUN pip3 install --upgrade https://github.com/kivy/buildozer/archive/d483847.zip
+# install buildozer & dependencies and enforces buildozer master (d483847) until next release
+RUN curl --location --progress-bar ${MAKEFILES_URL}/buildozer.mk --output /tmp/buildozer.mk && \
+    make --file /tmp/buildozer.mk && \
+    rm /tmp/buildozer.mk && \
+    pip3 install --no-cache-dir --upgrade https://github.com/kivy/buildozer/archive/d483847.zip
 
 COPY . ${WORK_DIR}
 ENTRYPOINT ["./dockerfiles/start.sh"]

dockerfiles/Dockerfile-linux

@@ -14,12 +14,13 @@ FROM ubuntu:18.04
 
 ENV USER="user"
 ENV HOME_DIR="/home/${USER}"
-ENV WORK_DIR="${HOME_DIR}"
+ENV WORK_DIR="${HOME_DIR}/app"
 
 # configure locale
-RUN apt update -qq > /dev/null && apt install --yes --no-install-recommends \
+RUN apt update -qq > /dev/null && apt install -qq --yes --no-install-recommends \
     locales && \
-    locale-gen en_US.UTF-8
+    locale-gen en_US.UTF-8 && \
+    rm -rf /var/lib/apt/lists/*
 ENV LANG="en_US.UTF-8" \
     LANGUAGE="en_US.UTF-8" \
     LC_ALL="en_US.UTF-8"
@@ -28,19 +29,22 @@ ENV LANG="en_US.UTF-8" \
 RUN apt update -qq > /dev/null && apt install -qq --yes --no-install-recommends \
     lsb-release \
     make \
-    sudo
+    sudo && \
+    rm -rf /var/lib/apt/lists/*
 
-# prepare non root env
-RUN useradd --create-home --shell /bin/bash ${USER}
-# with sudo access and no password
-RUN usermod -append --groups sudo ${USER}
-RUN echo "%sudo ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
+# prepare non root env, with sudo access and no password
+RUN useradd --create-home --home-dir ${HOME_DIR} --shell /bin/bash ${USER} && \
+    usermod -append --groups sudo ${USER} && \
+    echo "%sudo ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
 
 USER ${USER}
 WORKDIR ${WORK_DIR}
 
-COPY Makefile ${WORK_DIR}
-RUN sudo make system_dependencies_linux
+COPY Makefile /tmp/Makefile
+RUN sudo make --file /tmp/Makefile system_dependencies_linux && \
+    sudo rm /tmp/Makefile && \
+    sudo rm -rf /var/lib/apt/lists/*
+
 COPY . ${WORK_DIR}
 # required by Kivy `App.user_data_dir`
 RUN mkdir ~/.config