Image build is optimized.

.gitlab-ci.yml

@@ -23,7 +23,16 @@ variables:
   DOCKER_CPUS: "2"
 
 before_script:
-  - docker login -u $DOCKER_USER -p $DOCKER_PW
+  - docker login -u $DOCKER_HUB_USERNAME -p $DOCKER_HUB_PASSWORD
+  - docker system prune -a -f --volumes || true
+  - docker container prune -f || true
+  - docker network prune -f || true
+  - docker image prune -a -f || true
+  - docker builder prune -f || true
+  - sudo apt-get clean
+  - sudo rm -rf /var/lib/apt/lists/*
+  - sudo rm -rf /tmp/*
+  - sudo journalctl --vacuum-time=1s
 
 build:
   stage: build
@@ -32,10 +41,6 @@ build:
     - name: docker:dind
       command: ["--tls=false", "--storage-driver=overlay2", "--mtu=1500", "--data-root=/mnt/volume"]
   script:
-    - docker system prune -a -f --volumes || true
-    - docker container prune -f || true
-    - docker network prune -f || true
-    - docker image prune -a -f || true
     - docker build --cache-from=$DOCKER_REPO --no-cache --progress=plain -t $DOCKER_REPO -f flask_ml_api/Dockerfile .
     - docker push $DOCKER_REPO
   only: