feat: add specs to template

templates/docker-build.yml

+spec:
+    inputs:
+        stage:
+            description: Stage of the job.
+            default: build
+        image_id:
+            description: Image name and tag of the built image.
+            default: $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
+        context_path:
+            description: Path to the build context, usually the project.
+            default: .
+        dockerfile_name:
+            description: Name of the dockerfile.
+            default: Dockerfile
+        docker_host:
+            description: Docker daemon host URL.
+            default: tcp://docker:2375/
+        docker_driver:
+            description: Storage driver used by Docker.
+            default: overlay2
+        kaniko_options:
+            description: Additional options to pass to Kaniko for image building.
+            default: ""
+        kaniko_tag:
+            description: Version tag of the Kaniko executor image.
+            default: v1.23.2-debug
+
+---
 docker_build:
     stage: build
     variables:
-        DOCKER_HOST: tcp://docker:2375/
-        DOCKER_DRIVER: overlay2
-        TARGET_IMAGE: $CI_REGISTRY_IMAGE:$CI_COMMIT_SHA
-        PROJECT_PATH: .
-        KANIKO_OPTIONS: ""
+        DOCKER_HOST: $[[ inputs.docker_host ]]
+        DOCKER_DRIVER: $[[ inputs.docker_driver ]]
+        IMAGE_ID: $[[ inputs.image_id ]]
+        CONTEXT_PATH: $[[ inputs.context_path ]]
+        DOCKERFILE_NAME: $[[ inputs.dockerfile_name ]]
+        KANIKO_OPTIONS: $[[ inputs.kaniko_options ]]
+        KANIKO_TAG: $[[ inputs.kaniko_tag ]]
     image:
-        name: gcr.io/kaniko-project/executor:v1.14.0-debug
+        name: gcr.io/kaniko-project/executor:${KANIKO_TAG}
         entrypoint: [ "" ]
     tags:
         - docker
     script:
-        # Kaniko use $CI_REGISTRY_USER and $CI_REGISTRY_PASSWORD to connect to the
+        # Kaniko uses $CI_REGISTRY_USER and $CI_REGISTRY_PASSWORD to connect to the
         # registry
         - /kaniko/executor
-            --context "${PROJECT_PATH}"
-            --dockerfile "${PROJECT_PATH}/Dockerfile"
-            --destination "${TARGET_IMAGE}"
+            --context "${CONTEXT_PATH}"
+            --dockerfile "${CONTEXT_PATH}/${DOCKERFILE_NAME}"
+            --destination "${IMAGE_ID}"
             ${KANIKO_OPTIONS}