Optimize docker build time

Split `docker build` and `docker run` in two separate workflow steps
to reduce the output size in the github action and make it more readable

Also improve the docker (re)build speed by better using the cache: we
first copy the requirements.txt, then install, then copy the rest of the
folder, which means we won't invalidate the cached `pip install` step
unless we really need to

.github/workflows/main.yml

@@ -17,9 +17,13 @@ jobs:
         run: |
           mount | grep cgroup
 
+      - name: Build docker image
+        run: |
+          docker-compose -f docker-compose.test.yml build cms_test
+
       - name: Run tests
         run: |
-          docker-compose -f docker-compose.test.yml run cms_test
+          docker-compose -f docker-compose.test.yml run --rm cms_test
 
       - uses: codecov/codecov-action@v3
         with:

Dockerfile

@@ -35,12 +35,16 @@ RUN echo '%sudo ALL=(ALL) NOPASSWD:ALL' >> /etc/sudoers
 # Set cmsuser as default user
 USER cmsuser
 
-COPY --chown=cmsuser:cmsuser . /home/cmsuser/cms
+RUN mkdir /home/cmsuser/cms
+COPY --chown=cmsuser:cmsuser requirements.txt dev-requirements.txt /home/cmsuser/cms/
 
 WORKDIR /home/cmsuser/cms
 
 RUN sudo pip3 install -r requirements.txt
 RUN sudo pip3 install -r dev-requirements.txt
+
+COPY --chown=cmsuser:cmsuser . /home/cmsuser/cms
+
 RUN sudo python3 setup.py install
 
 RUN sudo python3 prerequisites.py --yes --cmsuser=cmsuser install