shrink

.travis.yml

@@ -16,7 +16,8 @@ before_script:
 script:
   - |
       set -e
-      docker build -t miniwdl --cache-from $DOCKER_CACHE_TAG .
+      docker build -t miniwdl_deps --target deps --cache-from $DOCKER_CACHE_TAG .
+      docker build -t miniwdl --cache-from miniwdl_deps .
       docker run --env TRAVIS_JOB_ID=${TRAVIS_JOB_ID} --env TRAVIS_BRANCH=${TRAVIS_BRANCH} \
                   --group-add $(stat -c %g /var/run/docker.sock) -v /var/run/docker.sock:/var/run/docker.sock -v /tmp:/tmp \
                   miniwdl make $CI_TARGET
@@ -29,7 +30,7 @@ jobs:
             # Push layers back to the registry for the next build(s) to use. From time to time, one
             # should delete the 'latest' tag via the quay.io website to trigger a refresh.
             if [ -n "$QUAY_PASSWORD" ]; then  # secure variable won't be available in others' PRs
-              docker tag miniwdl $DOCKER_CACHE_TAG
+              docker tag miniwdl_deps $DOCKER_CACHE_TAG
               echo "$QUAY_PASSWORD" | docker login -u mlin+miniwdl_ci --password-stdin quay.io
               docker push $DOCKER_CACHE_TAG
             fi

Dockerfile

@@ -5,7 +5,7 @@
 # or append 'bash' to that to enter interactive shell
 
 # start with ubuntu:18.04 plus some apt packages
-FROM ubuntu:18.04
+FROM ubuntu:18.04 as deps
 ENV LC_ALL C.UTF-8
 ENV LANG C.UTF-8
 RUN apt-get -qq update && DEBIAN_FRONTEND=noninteractive apt-get -qq install -y \
@@ -22,6 +22,7 @@ COPY requirements.txt requirements.dev.txt /home/wdler/
 RUN bash -o pipefail -c "pip3 install --user -r <(cat /home/wdler/requirements.txt /home/wdler/requirements.dev.txt)"
 
 # add the source tree
+FROM deps as all
 ADD --chown=wdler:wdler . /miniwdl
 WORKDIR /miniwdl