introducing buildx to the show

.gitlab-ci.yml

@@ -1,22 +1,35 @@
-image: docker:19.03.1
+buildx:
-services:
+  image: docker:19.03-git
-  - docker:19.03.1-dind
+  stage: buildx
-variables:
+  variables:
-  DOCKER_DRIVER: overlay
+    GIT_STRATEGY: none
-  DOCKER_TLS_CERTDIR: ""
+  artifacts:
-stages:
+    paths:
-  - build
+      - buildx
-
+    expire_in: 1 hour
-build:
-  image: docker:19.03.1
-  stage: build
   services:
-    - docker:19.03.1-dind
+    - docker:19.03-dind
+  script:
+    - export DOCKER_BUILDKIT=1
+    - git clone git://github.com/docker/buildx ./docker-buildx
+    - docker build --platform=local -o . ./docker-buildx
+
+deploy:
+  image: docker:19.03
+  stage: deploy
+  services:
+    - name: docker:19.03-dind
+      command: ["--experimental"]
+  before_script:
+    - mkdir -p ~/.docker/cli-plugins
+    - mv buildx ~/.docker/cli-plugins/docker-buildx
+    - docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
   variables:
     IMAGE_TAG: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG
   script:
     - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
-    - docker build -t $IMAGE_TAG .
+    - docker buildx create --use --name mybuilder
+    - docker buildx build --platform linux/amd64,linux/arm64,linux/arm/v7 --push -t $IMAGE_TAG .
     - docker push $IMAGE_TAG
     - docker build -t $CI_REGISTRY_IMAGE:latest .
     - docker push $CI_REGISTRY_IMAGE:latest