Build tagged versions for PHP 7.0, 7.1 and 7.2

.gitlab-ci.yml

 before_script:
   - docker login -u "$CI_REGISTRY_USER" -p "$CI_REGISTRY_PASSWORD" $CI_REGISTRY
 
-build-master:
+php-7.0:
   stage: build
   script:
-    - docker build --pull -t $CI_REGISTRY_IMAGE .
-    - docker push $CI_REGISTRY_IMAGE
+    - docker build --pull --build-arg PHP_VERSION=7.0 -t $CI_REGISTRY_IMAGE:php-7.0 .
+    - docker push $CI_REGISTRY_IMAGE:php-7.0
+  only:
+    - master
+
+php-7.1:
+  stage: build
+  script:
+    - docker build --pull --build-arg PHP_VERSION=7.1 -t $CI_REGISTRY_IMAGE:php-7.1 .
+    - docker push $CI_REGISTRY_IMAGE:php-7.1
+  only:
+    - master
+
+php-7.2:
+  stage: build
+  script:
+    - docker build --pull --build-arg PHP_VERSION=7.2 -t $CI_REGISTRY_IMAGE:php-7.2 .
+    - docker push $CI_REGISTRY_IMAGE:php-7.2
   only:
     - master

Dockerfile

-FROM registry.lakedrops.com/docker/gitlab-drupal-ci
+ARG PHP_VERSION
+
+FROM registry.lakedrops.com/docker/gitlab-drupal-ci:php-$PHP_VERSION
 
 LABEL com.example.vendor="LakeDrops" \
       maintainer="juergen.haas@lakedrops.com" \