Try to build the image once and push to both the GitLab and DockerHub registries.

.gitlab-ci.yml

@@ -11,7 +11,6 @@ before_script:
     stage: build
     variables:
         NO_CACHE: "true"
-        REPO_NAME: treemaker
         CONTEXT_DIR: "standalone/"
         IMAGE_NAME: cmssw
     tags:
@@ -23,12 +22,15 @@ before_script:
         # Build and push the image from the Dockerfile at the root of the project.
         # To push to a specific docker tag, amend the --destination parameter, e.g. --destination $CI_REGISTRY_IMAGE:$CI_BUILD_REF_NAME
         # See https://docs.gitlab.com/ee/ci/variables/predefined_variables.html#variables-reference for available variables
+        - echo "Pipeline source - $CI_PIPELINE_SOURCE"
+        - echo "Base image - $BASE_IMAGE"
+        - echo "Building standalone image ${CI_REGISTRY_IMAGE}/${IMAGE_NAME}:${CMSSW_VERSION}-${DATE}-${CI_COMMIT_SHORT_SHA} with ${CMSSW_VERSION} and ${SCRAM_ARCH}" on ${DATE}
         - echo ${CI_PROJECT_DIR}/${CONTEXT_DIR}/
         - ls -alh ${CI_PROJECT_DIR}/${CONTEXT_DIR}/
         - echo "Logging into the registry ${CI_REGISTRY}"
-        - echo "{\"auths\":{\"${CI_REGISTRY}\":{\"username\":\"${CI_REGISTRY_USER}\",\"password\":\"${CI_REGISTRY_PASSWORD}\"}}}" > /kaniko/.docker/config.json
-        - echo "Building standalone image ${CI_REGISTRY_IMAGE}/${IMAGE_NAME}:${CMSSW_VERSION}-${DATE}-${CI_COMMIT_SHORT_SHA} with ${CMSSW_VERSION} and ${SCRAM_ARCH}" on ${DATE}
-        - /kaniko/executor --context ${CI_PROJECT_DIR}/${CONTEXT_DIR} --dockerfile ${CI_PROJECT_DIR}/${CONTEXT_DIR}/Dockerfile --destination "${CI_REGISTRY_IMAGE}/${IMAGE_NAME}:${CMSSW_VERSION}-${DATE}-${CI_COMMIT_SHORT_SHA}" --build-arg=BUILD_DATE="${DATE}" --build-arg=VERSION="${DATE}" --build-arg=VCS_URL="${CI_REPOSITORY_URL}" --build-arg=VCS_REF="${CI_COMMIT_SHORT_SHA}" --build-arg BASEIMAGE="${BASE_IMAGE}" --build-arg SCRAM_ARCH="${SCRAM_ARCH}" --build-arg CMSSW_VERSION="${CMSSW_VERSION}"
+        - export DOCKER_AUTH="$(echo -n $DOCKER_USERNAME:$DOCKER_PASSWORD | base64)" # https://github.com/GoogleContainerTools/kaniko#pushing-to-docker-hub
+        - echo "{\"auths\":{\"${CI_REGISTRY}\":{\"username\":\"${CI_REGISTRY_USER}\",\"password\":\"${CI_REGISTRY_PASSWORD}\"}, \"${DOCKER_REGISTRY\":{\"auth\":\"${DOCKER_AUTH}\"}}}" > /kaniko/.docker/config.json
+        - /kaniko/executor --context ${CI_PROJECT_DIR}/${CONTEXT_DIR} --dockerfile ${CI_PROJECT_DIR}/${CONTEXT_DIR}/Dockerfile --destination "${CI_REGISTRY_IMAGE}/${IMAGE_NAME}:${CMSSW_VERSION}-${DATE}-${CI_COMMIT_SHORT_SHA}" --destination "${DOCKER_GROUP}/${IMAGE_NAME}:${CMSSW_VERSION}-${DATE}-${CI_COMMIT_SHORT_SHA}" --build-arg=BUILD_DATE="${DATE}" --build-arg=VERSION="${DATE}" --build-arg=VCS_URL="${CI_REPOSITORY_URL}" --build-arg=VCS_REF="${CI_COMMIT_SHORT_SHA}" --build-arg BASEIMAGE="${BASE_IMAGE}" --build-arg SCRAM_ARCH="${SCRAM_ARCH}" --build-arg CMSSW_VERSION="${CMSSW_VERSION}"
 
 # Jobs/Includes ---------------------------------------------------------------
 include:

standalone/.gitlab-ci.yml

@@ -4,14 +4,5 @@ build_TreeMaker_cmssw_standalone_CMSSW_10_6_25:
         CMSSW_VERSION: CMSSW_10_6_25
         SCRAM_ARCH: slc7_amd64_gcc700
         BASE_IMAGE: clelange/cc7-cms:latest
-
-build_TreeMaker_cmssw_standalone_CMSSW_10_6_25_dockerhub:
-    extends: .job_template
-    variables:
-        CMSSW_VERSION: CMSSW_10_6_25
-        SCRAM_ARCH: slc7_amd64_gcc700
-        BASE_IMAGE: clelange/cc7-cms:latest
-        CI_REGISTRY: https://index.docker.io/v1/
-        CI_REGISTRY_USER: ${DOCKER_USERNAME}
-        CI_REGISTRY_PASSWORD: ${DOCKER_PASSWORD}
-        CI_REGISTRY_IMAGE:	index.docker.io/${REPO_NAME}
\ No newline at end of file
+        DOCKER_GROUP: treemaker
+        DOCKER_REGISTRY: https://index.docker.io/v1/