init

.gitlab-ci.yml

+image: docker:latest
+
+services:
+  - docker:dind
+
+before_script:
+  - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
+
+build-master:
+  stage: build
+  script:
+    - docker build --pull -t "$CI_REGISTRY_IMAGE" .
+    - docker push "$CI_REGISTRY_IMAGE"
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Dockerfile

+FROM amazoncorretto:8-alpine-jdk
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