Resolve "extend gitlab-ci process"

Closes #3 (closed)

.gitlab-ci.yml

 stages:
-- image
+- build
+- publish
 - mirror
 
-'2.4':
-  stage: image
+docker_build_image_2.4:
+  stage: build
   image: docker:latest
   services:
   - docker:dind
   script: |
-    mkdir -p ~/.docker && echo "$DOCKER_AUTH_CONFIG" >~/.docker/config.json
-    export suffix=`expr $CI_COMMIT_TAG ':' '2.4-\(.*\)'`
     docker build --pull \
       --build-arg HTTP_PROXY=${HTTP_PROXY} \
       --build-arg HTTPS_PROXY=${HTTPS_PROXY} \
@@ -17,9 +16,65 @@ stages:
       --build-arg http_proxy=${HTTP_PROXY} \
       --build-arg https_proxy=${HTTPS_PROXY} \
       --build-arg no_proxy=${NO_PROXY} \
-      -t ubleipzig/httpd:2.4 \
+      -t image \
       -f 2.4/Dockerfile \
       2.4
+    docker save --output=image.tar.gz image
+  artifacts:
+    name: docker-image
+    paths:
+    - image.tar.gz
+  tags:
+  - docker
+
+docker_publish_alpha_2.4:
+  stage: publish
+  image: docker:latest
+  services:
+  - docker:dind
+  script: |
+    test "${DOCKER_AUTH_CONFIG}" == "" && echo "docker-config does not exists, aborting!" && false
+    mkdir -p ~/.docker && echo "$DOCKER_AUTH_CONFIG" >~/.docker/config.json
+    docker load --input=image.tar.gz
+    docker tag image ubleipzig/httpd:alpha-2.4-${CI_COMMIT_REF_NAME}
+    docker push ubleipzig/httpd:alpha-2.4-${CI_COMMIT_REF_NAME}
+  tags:
+  - docker
+  dependencies:
+  - docker_build_image_2.4
+  only:
+  - /^[0-9]+-/
+
+docker_publish_staging_2.4:
+  stage: publish
+  image: docker:latest
+  services:
+  - docker:dind
+  script: |
+    test "${DOCKER_AUTH_CONFIG}" == "" && echo "docker-config does not exists, aborting!" && false
+    mkdir -p ~/.docker && echo "$DOCKER_AUTH_CONFIG" >~/.docker/config.json
+    docker load --input=image.tar.gz
+    docker tag image ubleipzig/httpd:staging
+    docker push ubleipzig/httpd:staging
+  tags:
+  - docker
+  dependencies:
+  - docker_build_image_2.4
+  only:
+  - master
+
+docker_publish_production_2.4:
+  stage: publish
+  image: docker:latest
+  services:
+  - docker:dind
+  script: |
+    test "${DOCKER_AUTH_CONFIG}" == "" && echo "docker-config does not exists, aborting!" && false
+    mkdir -p ~/.docker && echo "$DOCKER_AUTH_CONFIG" >~/.docker/config.json
+    suffix=`expr $CI_COMMIT_TAG ':' '2.4-\(.*\)'`
+
+    docker load --input=image.tar.gz
+    docker tag image ubleipzig/httpd:2.4
     docker push ubleipzig/httpd:2.4
     for tag in "latest" "2" "2.4-${suffix}"; do
       docker tag ubleipzig/httpd:2.4 ubleipzig/httpd:${tag}
@@ -27,8 +82,10 @@ stages:
     done
   tags:
   - docker
+  dependencies:
+  - docker_build_image_2.4
   only:
-  - /^2.4/
+  - /^2.4-/
   except:
   - branches