Convert to multi-stage build

This should result in smaller images.

Signed-off-by: Stephen Finucane <[email protected]>

Author: stephenfin

Dockerfile

@@ -1,11 +1,38 @@
-FROM ubuntu:20.04
+FROM ubuntu:20.04 AS base
 
 ENV LANG="C.UTF-8"
 ENV LC_ALL="C.UTF-8"
 ENV PATH="/opt/pyenv/shims:/opt/pyenv/bin:$PATH"
 ENV PYENV_ROOT="/opt/pyenv"
 ENV PYENV_SHELL="bash"
 
+# runtime dependencies
+RUN apt-get update --quiet && \
+    apt-get install -y --no-install-recommends \
+        bzip2 \
+        ca-certificates \
+        curl \
+        git \
+        libexpat1 \
+        $(apt-cache search --names-only 'libffi[0-9]+$' 2>/dev/null | awk '{print $1}') \
+        $(apt-cache search --names-only 'libmpdec[0-9]+$' 2>/dev/null | awk '{print $1}') \
+        libncursesw5 \
+        $(apt-cache show libncursesw6 >/dev/null 2>&1 && echo libncursesw6 || true) \
+        $(apt-cache search --names-only 'libreadline[0-9]+$' 2>/dev/null | awk '{print $1}') \
+        libsqlite3-0 \
+        libssl1.1 \
+        lzma \
+        zlib1g
+
+RUN curl -L https://github.com/pyenv/pyenv-installer/raw/master/bin/pyenv-installer | bash && \
+    git clone https://github.com/momo-lab/xxenv-latest $PYENV_ROOT/plugins/xxenv-latest && \
+    pyenv update
+
+# ---
+
+FROM base as build
+
+# builder dependencies
 RUN apt-get update && apt-get install -y --no-install-recommends \
     build-essential \
     ca-certificates \
@@ -18,14 +45,26 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     libssl-dev \
     zlib1g-dev
 
-RUN curl -L https://github.com/pyenv/pyenv-installer/raw/master/bin/pyenv-installer | bash && \
-    git clone https://github.com/momo-lab/xxenv-latest $PYENV_ROOT/plugins/xxenv-latest && \
-    pyenv update
-
 RUN pyenv latest install 3.6 && \
     pyenv latest install 3.7 && \
     pyenv latest install 3.8 && \
-    pyenv latest install 3.9
-RUN pyenv global $(pyenv versions --bare | tac)
+    pyenv latest install 3.9 && \
+    pyenv global $(pyenv versions --bare | tac) && \
+    pyenv versions && \
+    find ${PYENV_ROOT}/versions -depth \
+        \( \
+            \( -type d -a \( -name test -o -name tests -o -name idle_test \) \) \
+            -o \( -type f -a \( -name '*.pyc' -o -name '*.pyo' -o -name '*.a' \) \) \
+            -o \( -type f -a -name 'wininst-*.exe' \) \
+        \) -exec rm -rf '{}' +  && \
+    pip install tox tox-pyenv
+
+# ---
+
+FROM base
+
+COPY --from=build ${PYENV_ROOT}/versions/ ${PYENV_ROOT}/versions/
 
-RUN pip install tox tox-pyenv
+RUN pyenv rehash && \
+    pyenv global $(pyenv versions --bare | tac) && \
+    pyenv versions