Merge pull request #16 from splunk/ISSUE-3

Issue 3

Author: micahkemp-splunk

build.yml

@@ -3,8 +3,16 @@
   # so set gather_facts to no here, and run setup explicitly in the role
   gather_facts: no
   roles:
+    - role: docker_skip_hosts_in_registry
+      delegate_to: "{{ groups['docker_build_hosts'] | first }}"
+      tags:
+        - never
+        - skip-if-in-registry
+
     - role: docker_build_gather_facts
       delegate_to: "{{ groups['docker_build_hosts'] | first }}"
+      when: not skip_build_and_push
 
     - role: docker_image_build
       delegate_to: "{{ groups['docker_build_hosts'] | first }}"
+      when: not skip_build_and_push

group_vars/all.yml

@@ -48,3 +48,6 @@ role_build_variants:
   - build_vars:
       primary_build: false
       tag: "{{ version }}-standalone"
+
+# skip_build_and_push is overrideable by using the skip-if-in-registry tag, but defaults to false to always perform the build
+skip_build_and_push: false

push.yml

@@ -2,5 +2,12 @@
   # nothing here should rely on gathered facts
   gather_facts: no
   roles:
+    - role: docker_skip_hosts_in_registry
+      delegate_to: "{{ groups['docker_build_hosts'] | first }}"
+      tags:
+        - never
+        - skip-if-in-registry
+
     - role: docker_image_push
       delegate_to: "{{ groups['docker_build_hosts'] | first }}"
+      when: not skip_build_and_push

roles/docker_skip_hosts_in_registry/tasks/clear_skip_if_missing.yml

@@ -0,0 +1,16 @@
+- block:
+    - name: "check if {{ repository_push_image }} is missing from the registry"
+      command: "docker manifest inspect {{ repository_push_image }}"
+      become: "{{ docker_become_user is defined }}"
+      become_user: "{{ docker_become_user|default(omit) }}"
+      environment:
+        DOCKER_CLI_EXPERIMENTAL: enabled
+      # we don't need to keep checking after clearing skip_build_and_push
+      # only build variants that are configured to push with this configuration should be checked
+      when: (build_vars.push_when | default(false)) and skip_build_and_push
+
+  # when the image doesn't exist in the registry the above returns a non-zero, causing an exception
+  rescue:
+    - name: image is missing, clear skip_build_and_push
+      set_fact:
+        skip_build_and_push: false

roles/docker_skip_hosts_in_registry/tasks/main.yml

@@ -0,0 +1,11 @@
+- name: set default to skip build and push
+  set_fact:
+    skip_build_and_push: true
+
+- name: run clear_skip_if_missing for each variant
+  include_tasks: clear_skip_if_missing.yml
+  vars:
+    build_vars: "{{ build_variant.build_vars }}"
+  loop: "{{ build_variants }}"
+  loop_control:
+    loop_var: build_variant