[ENH] lighter alpine multi-stage build docker image, ~65% smaller

.github/workflows/docker.yml

@@ -7,6 +7,9 @@ on:
 
 jobs:
   build-docker:
+    strategy:
+      matrix:
+        version: ["", "-alpine"]
     runs-on: ubuntu-latest
     steps:
       - name: Checkout source
@@ -23,18 +26,20 @@ jobs:
         run: |
           # build only if not release tag, i.e. has some "-" in describe
           # so we do not duplicate work with release workflow.
+          dockerfile=Dockerfile${version/-/.}
           git describe --match 'v[0-9]*' | grep -q -e - && \
               docker build \
-                -t nipy/heudiconv:master \
-                -t nipy/heudiconv:unstable \
-                .
+                -t nipy/heudiconv:master${version} \
+                -t nipy/heudiconv:unstable${version} \
+                . \
+                -f $dockerfile
 
       - name: Push Docker image
         run: |
           git describe --match 'v[0-9]*' | grep -q -e - && (
               docker login -u "$DOCKER_LOGIN" --password-stdin <<<"$DOCKER_TOKEN"
-              docker push nipy/heudiconv:master
-              docker push nipy/heudiconv:unstable
+              docker push nipy/heudiconv:master${version}
+              docker push nipy/heudiconv:unstable${version}
           )
         env:
           DOCKER_LOGIN: ${{ secrets.DOCKER_LOGIN }}

Dockerfile.alpine

@@ -0,0 +1,34 @@
+FROM python:3.10-alpine AS builder
+
+RUN apk add bash \
+  gcc \
+  g++ \
+  libc-dev \
+  make \
+  cmake \
+  util-linux-dev \
+  curl \
+  git
+RUN pip install --no-cache-dir pylibjpeg-libjpeg traits==6.3.2
+
+ARG DCM2NIIX_VERSION=v1.0.20240202
+RUN git clone https://github.com/rordenlab/dcm2niix /tmp/dcm2niix \
+  && cd /tmp/dcm2niix \
+  && git fetch --tags \
+  && git checkout $DCM2NIIX_VERSION \
+  && mkdir /tmp/dcm2niix/build \
+  && cd /tmp/dcm2niix/build \
+  && cmake -DZLIB_IMPLEMENTATION=Cloudflare -DUSE_JPEGLS=ON -DUSE_OPENJPEG=ON -DCMAKE_INSTALL_PREFIX:PATH=/usr/ .. \
+  && make -j1 \
+  && make install \
+  && rm -rf /tmp/dcm2niix
+
+FROM python:3.10-alpine
+COPY --from=builder /usr/local/lib/python3.10/site-packages /usr/local/lib/python3.10/site-packages
+COPY --from=builder /usr/bin/dcm2niix /usr/bin/dcm2niix
+
+RUN apk update && apk add --no-cache git git-annex pigz gcompat
+
+RUN pip install --no-cache-dir heudiconv
+
+ENTRYPOINT ["heudiconv"]