CI pipeline for building Docker images at Kubenertes cluster with Kaniko (env flag customization also available)

kaniko-build-docker-image.yml

stages:
  - build

variables:
  REGISTRY_IMAGE_PATH: "${CI_REGISTRY}/${CI_PROJECT_NAMESPACE}/${CI_PROJECT_NAME}:${CI_COMMIT_SHORT_SHA}"
  PUSH_IMAGE: "true"
  GIT_DEPTH: 1
  DOCKER_FILE_NAME: "Dockerfile"

kaniko-build-docker-image:
  stage: build
  image:
    name: gcr.io/kaniko-project/executor:debug
    entrypoint: [""]
  only:
    - main
    - develop
    - testing
  script:
    - |
      if [ -z "${REGISTRY_IMAGE_PATH}" ]; then
        echo "ERROR: CI variable REGISTRY_IMAGE_PATH is mandatory."
        exit 1
      fi
    - REGISTRY=$(echo ${REGISTRY_IMAGE_PATH} | cut -d / -f 1)
    - >
      if [ -z "${CONTEXT_DIR}" ]; then
        KANIKO_CONTEXT_DIR=${CI_PROJECT_DIR}
      else
        KANIKO_CONTEXT_DIR=${CI_PROJECT_DIR}/${CONTEXT_DIR}
      fi
    - mkdir -p /kaniko/.docker
    - |
      if [ -z "$DOCKER_AUTH_CONFIG" ]; then
        # build the DOCKER_AUTH_CONFIG from user parameters as per https://docs.gitlab.com/ee/ci/docker/using_kaniko.html and internal docs
        echo "{\"auths\":{\"${REGISTRY}\":{\"auth\":\"$(printf "%s:%s" "${CI_REGISTRY_USER}" "${CI_REGISTRY_PASSWORD}" | base64 | tr -d '\n')\"}}}" > /kaniko/.docker/config.json
      else
        echo "${DOCKER_AUTH_CONFIG}" > /kaniko/.docker/config.json
      fi
    # build and push the image to the path set in $REGISTRY_IMAGE_PATH variable.
    - |
      if [ "$(echo ${PUSH_IMAGE} | tr '[:upper:]' '[:lower:]')" = "true" ]; then
        PUSH_IMAGE=""
      else
        echo "Info: defer pushing image to remote as PUSH_IMAGE is false"
        PUSH_IMAGE="--no-push"
      fi
    - |
      if [ "$(echo ${ACCELERATED_IMAGE} | tr '[:upper:]' '[:lower:]')" = "true" ]; then
        export GGCR_EXPERIMENT_ESTARGZ=1
      fi
    - |
      if [ -n "$BUILD_ARGS" ]; then
        for arg in $BUILD_ARGS; do
          KANIKO_BUILD_ARGS="${KANIKO_BUILD_ARGS} --build-arg ${arg}"
        done
      fi
    - echo "KANIKO_CONTEXT_DIR - $KANIKO_CONTEXT_DIR \n DOCKER_FILE_NAME = $DOCKER_FILE_NAME \n KANIKO_BUILD_ARGS = $KANIKO_BUILD_ARGS"
    - /kaniko/executor --context "${KANIKO_CONTEXT_DIR}" --dockerfile "${KANIKO_CONTEXT_DIR}/${DOCKER_FILE_NAME}" ${KANIKO_BUILD_ARGS} --destination "${REGISTRY_IMAGE_PATH}" "${PUSH_IMAGE}"