Container build without Docker

With this MR we use Kaniko instead of Docker to build our images. This way, we can also build and push them without Docker-in-Docker.

.gitlab-ci.yml

@@ -309,6 +309,33 @@ deploy-theodolite:
       when: manual
       allow_failure: true
 
+deploy-theodolite-kaniko:
+  stage: deploy
+  extends:
+    - .theodolite
+  needs:
+    - build-theodolite-jvm
+    - test-theodolite
+  image:
+    name: gcr.io/kaniko-project/executor:debug
+    entrypoint: [""]
+  before_script:
+    - mkdir -p /kaniko/.docker
+    - echo "{\"auths\":{\"${CR_HOST}\":{\"auth\":\"$(printf "%s:%s" "${CR_USER}" "${CR_PW}" | base64 | tr -d '\n')\"}}}" > /kaniko/.docker/config.json
+  script:
+    - DOCKER_TAG_NAME=$(echo $CI_COMMIT_REF_SLUG- | sed 's/^master-$//')
+    - /kaniko/executor --context $PWD --dockerfile $PWD/src/main/docker/Dockerfile.jvm -d $CR_HOST/$CR_ORG/theodolite:${DOCKER_TAG_NAME}latest-kaniko
+  rules:
+    - if: "$CR_HOST && $CR_ORG && $CR_USER && $CR_PW && $CI_COMMIT_TAG"
+      when: always
+    - changes:
+      - theodolite/**/*
+      if: "$CR_HOST && $CR_ORG && $CR_USER && $CR_PW"
+      when: always
+    - if: "$CR_HOST && $CR_ORG && $CR_USER && $CR_PW"
+      when: manual
+      allow_failure: true
+
 
 # Theodolite SLO Checker: Lag Trend