add rules to ci for build only when some files changed

.gitlab-ci.yml

@@ -1,19 +1,47 @@
 stages:
   - build
 
-build_images:
+golang:
   stage: build
   tags:
     - gobuild
-  rules:
-    - if: $CI_COMMIT_BRANCH == "main"
+  only:
+    changes:
+      - golang/Dockerfile
   before_script:
     - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
   script:
     - docker build -t $CI_REGISTRY_IMAGE/golang:$CI_COMMIT_REF_SLUG.$CI_PIPELINE_ID $CI_PROJECT_DIR/golang
     - docker push $CI_REGISTRY_IMAGE/golang:$CI_COMMIT_REF_SLUG.$CI_PIPELINE_ID
+  after_script:
+    - docker system prune --all --volumes --force
+
+alpine:
+  stage: build
+  tags:
+    - gobuild
+  only:
+    changes:
+      - alpine/Dockerfile
+  before_script:
+    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+  script:
     - docker build -t $CI_REGISTRY_IMAGE/alpine:$CI_COMMIT_REF_SLUG.$CI_PIPELINE_ID $CI_PROJECT_DIR/alpine
     - docker push $CI_REGISTRY_IMAGE/alpine:$CI_COMMIT_REF_SLUG.$CI_PIPELINE_ID
+  after_script:
+    - docker system prune --all --volumes --force
+
+golint:
+  stage: build
+  tags:
+    - gobuild
+  only:
+    changes:
+      - golint/Dockerfile
+      - golint/golangci-lint
+  before_script:
+    - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
+  script:
     - docker build -t $CI_REGISTRY_IMAGE/golint:$CI_COMMIT_REF_SLUG.$CI_PIPELINE_ID $CI_PROJECT_DIR/golint
     - docker push $CI_REGISTRY_IMAGE/golint:$CI_COMMIT_REF_SLUG.$CI_PIPELINE_ID
   after_script: