generator: add support for extra vars usage (#84544)

* generator: add support for extra vars usage

Fixes: #83270

Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>

* CI green

Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>

* Review requests

Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>

* Review requests II

Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>

---------

Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>

test/integration/targets/inventory_generator/aliases

@@ -0,0 +1 @@
+shippable/posix/group5

test/integration/targets/inventory_generator/extra_vars_generator.yml

@@ -0,0 +1,8 @@
+plugin: ansible.builtin.generator
+use_extra_vars: True
+hosts:
+    name: "{{ region }}_{{ machine_type }}"
+layers:
+    machine_type:
+        - web
+        - db

test/integration/targets/inventory_generator/generator.yml

@@ -0,0 +1,10 @@
+plugin: ansible.builtin.generator
+hosts:
+    name: "{{ region }}_{{ machine_type }}"
+layers:
+    machine_type:
+        - web
+        - db
+    region:
+        - mumbai
+        - pune

test/integration/targets/inventory_generator/generator_parent.yml

@@ -0,0 +1,18 @@
+plugin: ansible.builtin.generator
+hosts:
+    name: "{{ application }}_{{ operation }}_runner"
+    parents:
+        - name: "{{ environment }}"
+          vars:
+            log: "s"
+layers:
+    operation:
+        - build
+        - launch
+    environment:
+        - dev
+        - test
+        - prod
+    application:
+        - web
+        - api

test/integration/targets/inventory_generator/runme.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+set -eux
+
+ansible-inventory -i generator.yml --graph | tee out.txt
+
+grep 'mumbai_web' out.txt
+grep 'mumbai_db' out.txt
+grep 'pune_web' out.txt
+grep 'pune_db' out.txt
+
+ANSIBLE_INVENTORY_USE_EXTRA_VARS=True ansible-inventory -i extra_vars_generator.yml --graph -e "region=pune"
+
+grep 'pune_web' out.txt
+grep 'pune_db' out.txt
+
+ansible-inventory -i generator_parent.yml --graph | tee out.txt
+
+grep 'web_build_runner' out.txt
+grep 'api_build_runner' out.txt
+grep 'web_launch_runner' out.txt
+grep 'api_launch_runner' out.txt
+grep '@dev' out.txt
+grep '@test' out.txt
+grep '@prod' out.txt