From 353dc3d050bf22c0057b76d7208dd1a94c5798bc Mon Sep 17 00:00:00 2001
From: Dmitriy Rabotyagov <noonedeadpunk@ya.ru>
Date: Fri, 25 Sep 2020 18:29:03 +0300
Subject: [PATCH] Define condition for the first play host one time

We use the same condition, which defines against what host some "service"
tasks should run against, several times. It's hard to keep it the same
across the role and ansible spending additional resources to evaluate
it each time, so it's simpler and better for the maintenance to set
a boolean variable which will say for all tasks, that we want to run
only against signle host, if they should run or not now.

Change-Id: I5c92722d5e7c49d0a01c7e9dbd0b254b5bea6dc4
---
 tasks/main.yml | 8 ++++----
 vars/main.yml  | 1 +
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/tasks/main.yml b/tasks/main.yml
index 23aea3c..51ba752 100644
--- a/tasks/main.yml
+++ b/tasks/main.yml
@@ -29,7 +29,7 @@
 
 - import_tasks: db_setup.yml
   when:
-    - inventory_hostname == groups['tacker_all'][0]
+    - _tacker_is_first_play_host
   vars:
     _oslodb_setup_host: "{{ tacker_db_setup_host }}"
     _oslodb_ansible_python_interpreter: "{{ tacker_db_setup_python_interpreter }}"
@@ -46,7 +46,7 @@
 
 - import_tasks: mq_setup.yml
   when:
-    - inventory_hostname == groups['tacker_all'][0]
+    - _tacker_is_first_play_host
   vars:
     _oslomsg_rpc_setup_host: "{{ tacker_oslomsg_rpc_setup_host }}"
     _oslomsg_rpc_userid: "{{ tacker_oslomsg_rpc_userid }}"
@@ -114,7 +114,7 @@
 
 - import_tasks: tacker_db_sync.yml
   when:
-    - inventory_hostname == groups['tacker_all'][0]
+    - _tacker_is_first_play_host
   tags:
     - tacker-install
 
@@ -145,7 +145,7 @@
         type: "{{ tacker_service_type }}"
         description: "{{ tacker_service_description }}"
   when:
-    - inventory_hostname == groups['tacker_all'][0]
+    - _tacker_is_first_play_host
   tags:
     - tacker-install
 
diff --git a/vars/main.yml b/vars/main.yml
index 35f370d..96d474d 100644
--- a/vars/main.yml
+++ b/vars/main.yml
@@ -15,3 +15,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+_tacker_is_first_play_host: "{{ ('tacker_all' in group_names and inventory_hostname == (groups['tacker_all'] | intersect(ansible_play_hosts)) | first) | bool }}"