Only gather facts once. Use "image" instead of "inventory_hostname" t…

…o set the image name.

roles/gather_facts/tasks/main.yml → roles/docker_build_gather_facts/tasks/main.yml

@@ -1,4 +1,6 @@
 # gather facts via setup in the role, which is after delegation
 # we want to enable inventory configurations to make use of collected facts (like ansible_date_time)
+# because this is set to run once, it only makes sense to call this role with delegation
 - name: run setup to gather facts
   setup:
+  run_once: true

roles/docker_service_build/tasks/docker_build.yml

@@ -1,6 +1,6 @@
 - name: remove old docker image
   docker_image:
-    name: "{{ inventory_hostname }}{% if not production_image %}_dev{% endif %}"
+    name: "{{ image }}{% if not production_image %}_dev{% endif %}"
     tag: "{{ tags.build }}"
     state: absent
   become: yes
@@ -11,7 +11,7 @@
     DOCKER_BUILDKIT: "1"
   docker_image:
     path: "{{ docker_build_directory.path }}"
-    name: "{{ inventory_hostname }}{% if not production_image %}_dev{% endif %}"
+    name: "{{ image }}{% if not production_image %}_dev{% endif %}"
     tag: "{{ tags.build }}"
     push: no
   become: yes