yarn/tasks/main.yml: Support skip_role_on_error flag

roles/yarn/tasks/main.yml

@@ -26,23 +26,31 @@
     var: yarn_installed
 
 
-- name: Install Yarn if 'yarn_installed' not defined, e.g. in {{ iiab_state_file }}    # /etc/iiab/iiab_state.yml
-  include_tasks: install.yml
-  when: yarn_installed is undefined
+- block:
 
+  - name: Install Yarn if 'yarn_installed' not defined, e.g. in {{ iiab_state_file }}    # /etc/iiab/iiab_state.yml
+    include_tasks: install.yml
+    when: yarn_installed is undefined
 
-- name: Add 'yarn' variable values to {{ iiab_ini_file }}
-  ini_file:
-    path: "{{ iiab_ini_file }}"    # /etc/iiab/iiab.ini
-    section: yarn
-    option: "{{ item.option }}"
-    value: "{{ item.value | string }}"
-  with_items:
-    - option: name
-      value: Yarn
-    - option: description
-      value: '"Fast, reliable, and secure dependency management.  Comparable to npm.  Released by Facebook in October 2016."'
-    - option: yarn_install
-      value: "{{ yarn_install }}"
-    - option: yarn_enabled
-      value: "{{ yarn_enabled }}"
+  - name: Add 'yarn' variable values to {{ iiab_ini_file }}
+    ini_file:
+      path: "{{ iiab_ini_file }}"    # /etc/iiab/iiab.ini
+      section: yarn
+      option: "{{ item.option }}"
+      value: "{{ item.value | string }}"
+    with_items:
+      - option: name
+        value: Yarn
+      - option: description
+        value: '"Fast, reliable, and secure dependency management.  Comparable to npm.  Released by Facebook in October 2016."'
+      - option: yarn_install
+        value: "{{ yarn_install }}"
+      - option: yarn_enabled
+        value: "{{ yarn_enabled }}"
+
+  rescue:
+
+  - name: 'SEE ERROR ABOVE (skip_role_on_error: {{ skip_role_on_error }})'
+    fail:
+      msg: ""
+    when: not skip_role_on_error