Update dockerfile to have less layers and use pyenv to determine versions

Author: terencehonles

Dockerfile

@@ -2,52 +2,88 @@ FROM ubuntu:18.04
 
 MAINTAINER Florian Finke <florian@finke.email>
 
-ENV PYTHON_VERSIONS 2.7.13 2.7.14 2.7.15 2.7.16 2.7.17 2.7.18 3.0.1 3.1.0 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5 3.2.0 3.2.1 3.2.2 3.2.3 3.2.4 3.2.5 3.2.6 3.3.0 3.3.1 3.3.2 3.3.3 3.3.4 3.3.5 3.3.6 3.3.7 3.4.0 3.4.1 3.4.2 3.4.3 3.4.4 3.4.5 3.4.6 3.4.7 3.4.8 3.4.9 3.4.10 3.5.0 3.5.1 3.5.2 3.5.3 3.5.4 3.5.5 3.5.6 3.5.7 3.5.8 3.5.9 3.5.10 3.6.0 3.6.1 3.6.2 3.6.3 3.6.4 3.6.5 3.6.6 3.6.7 3.6.8 3.6.9 3.6.10 3.6.11 3.6.12 3.7.0 3.7.1 3.7.2 3.7.3 3.7.4 3.7.5 3.7.6 3.7.7 3.7.8 3.7.9 3.8.0 3.8.1 3.8.2 3.8.3 3.8.4 3.8.5 3.8.6 3.9.0
+# tools installed below may need these for their installations
+ENV LANG=en_US.UTF-8
+ENV LC_ALL=C.UTF-8
+ENV PYTHONIOENCODING=UTF-8
+
+RUN set -ex \
+    && export DEBIAN_FRONTEND=noninteractive \
+    && apt-get update \
+    # install curl and its recommendations (HTTPs support, etc)
+    && apt-get install -y curl \
+    && curl -sL https://deb.nodesource.com/setup_12.x > setup-node.sh \
+    && bash setup-node.sh \
+    && rm setup-node.sh \
+    && apt-get install --no-install-recommends --fix-missing -y \
+        build-essential \
+        curl \
+        git \
+        libbz2-dev \
+        libffi-dev \
+        libfontconfig \
+        libjpeg-dev \
+        libreadline-dev \
+        libsqlite3-dev \
+        libssl1.0-dev \
+        libxml2-dev \
+        libxslt1-dev \
+        locales \
+        make \
+        nodejs \
+        openssh-client \
+        python3-dev \
+        python3-lxml \
+        python3-pil \
+        rsync \
+        ruby-dev \
+        rubygems \
+        zlib1g-dev \
+    && echo -e "Host *\n\tStrictHostKeyChecking no\n\n" > /etc/ssh/ssh_config \
+    # Install the most up to date pip (This will include setuptools)
+    && curl -sL https://bootstrap.pypa.io/get-pip.py > get-pip.py \
+    && python3 get-pip.py \
+    && rm get-pip.py \
+    # install global tools
+    && pip3 install --upgrade tox tox-pyenv awscli awsebcli \
+    && npm install -g npm@latest yarn \
+    # clean caches
+    && apt-get autoremove -y \
+    && apt-get clean all \
+    && rm -rf /var/lib/apt/lists/* \
+    # generate locale
+    && echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen \
+    && locale-gen \
+    && update-locale LANG=en_US.UTF-8
 
-ENV DEBIAN_FRONTEND=noninteractive
+ARG PYENV_UPDATED_AT
+RUN if [ -z "$PYENV_UPDATED_AT" ]; then \
+        echo >&2 'Build with docker build argument --build-arg=PYENV_UPDATED_AT=$(date +%Y-%m-%d)' ; \
+        exit 1 ; \
+    fi
+ENV PYENV_UPDATED_AT=$PYENV_UPDATED_AT
 
+# pyenv ENV VARS
 ENV PYENV_ROOT /pyenv/
 ENV PATH /pyenv/shims:/pyenv/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
 ENV PYENV_INSTALLER_ROOT /pyenv-installer/
 ENV PYENV_REQUIRED_PYTHON_BASENAME python_versions.txt
 ENV PYENV_REQUIRED_PYTHON /pyenv-config/$PYENV_REQUIRED_PYTHON_BASENAME
 
-RUN apt-get update -q -y
-RUN apt-get install --no-install-recommends --fix-missing -y build-essential \
-    python3-dev python3-pip git make locales libssl1.0-dev \
-    libfontconfig libffi-dev libbz2-dev libreadline-dev libsqlite3-dev \
-    libjpeg-dev zlib1g-dev python3-pil libxml2-dev \
-    libxslt1-dev python3-lxml openssh-client \
-    curl rsync ruby-dev rubygems \
-    && apt-get autoremove -y \
-        && apt-get clean all \
-        && rm -rf /var/lib/apt/lists/*
-
-RUN echo "en_US.UTF-8 UTF-8" >> /etc/locale.gen \
-        && locale-gen \
-        && update-locale LANG=en_US.UTF-8
-
-ENV LANG=en_US.UTF-8
-ENV LC_ALL=C.UTF-8
-ENV PYTHONIOENCODING=UTF-8
-
-RUN pip3 install --upgrade setuptools
-RUN pip3 install --upgrade tox tox-pyenv awscli awsebcli
-
-RUN mkdir -p ~/.ssh
-RUN echo "Host *\n\tStrictHostKeyChecking no\n\n" > ~/.ssh/config
-
-RUN curl -sL https://deb.nodesource.com/setup_12.x | bash
-RUN apt-get -y install nodejs
-
-RUN npm install -g npm@latest yarn
-
-RUN git clone https://github.com/pyenv/pyenv.git $PYENV_ROOT
-
-COPY python_versions.txt $PYENV_REQUIRED_PYTHON
-RUN while read line; do \
-    pyenv install $line || exit 1 ;\
-    done < $PYENV_REQUIRED_PYTHON
+# setup Python versions
+RUN set -ex \
+    && git clone https://github.com/pyenv/pyenv.git $PYENV_ROOT \
+    && export PYTHON3_VERSIONS="$(\
+        /pyenv/plugins/python-build/bin/python-build --definitions \
+            | grep  '^3' | grep -v -- '-dev$' | xargs)" \
+    # manually specify the 2.7.x versions since it is not all of them
+    && export PYTHON_VERSIONS="2.7.13 2.7.14 2.7.15 2.7.16 2.7.17 2.7.18 $PYTHON3_VERSIONS" \
+    && mkdir /pyenv-config/ \
+    && echo "$PYTHON_VERSIONS" | tr ' ' '\n' > $PYENV_REQUIRED_PYTHON \
+    && for version in $PYTHON_VERSIONS; do \
+        pyenv install $version || exit 1 ; \
+    done \
+    && pyenv global $PYTHON_VERSIONS \
+    && pyenv local $PYTHON_VERSIONS
 
-RUN pyenv global $PYTHON_VERSIONS
-RUN pyenv local $PYTHON_VERSIONS
+ENTRYPOINT ["/bin/sh", "-c", "export PYTHON_VERSIONS=\"$(cat $PYENV_REQUIRED_PYTHON)\" && exec \"$@\""]