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>

changelogs/fragments/generator_use_extra.yml

@@ -0,0 +1,3 @@
+---
+minor_changes:
+  - generator - add support for extra vars (https://github.com/ansible/ansible/issues/83270).

lib/ansible/plugins/inventory/generator.py

@@ -32,6 +32,20 @@ DOCUMENTATION = """
         description:
           - A dictionary of layers, with the key being the layer name, used as a variable name in the C(host)
             C(name) and C(parents) keys. Each layer value is a list of possible values for that layer.
+      use_extra_vars:
+        version_added: '2.19'
+        description:
+          - Merge extra vars into the available variables for composition (highest precedence).
+        type: bool
+        default: false
+        ini:
+          - section: inventory_plugins
+            key: use_extra_vars
+          - section: inventory_plugin_generator
+            key: use_extra_vars
+        env:
+          - name: ANSIBLE_INVENTORY_USE_EXTRA_VARS
+          - name: ANSIBLE_GENERATOR_USE_EXTRA_VARS
 """
 
 EXAMPLES = """
@@ -77,6 +91,7 @@ from itertools import product
 from ansible import constants as C
 from ansible.errors import AnsibleParserError
 from ansible.plugins.inventory import BaseInventoryPlugin
+from ansible.utils.vars import load_extra_vars
 
 
 class InventoryModule(BaseInventoryPlugin):
@@ -123,10 +138,14 @@ class InventoryModule(BaseInventoryPlugin):
         super(InventoryModule, self).parse(inventory, loader, path, cache=cache)
 
         config = self._read_config_data(path)
-
+        if self.get_option('use_extra_vars'):
+            extra_vars = load_extra_vars(loader)
+        else:
+            extra_vars = {}
         template_inputs = product(*config['layers'].values())
         for item in template_inputs:
             template_vars = dict()
+            template_vars.update(extra_vars)
             for i, key in enumerate(config['layers'].keys()):
                 template_vars[key] = item[i]
             host = self.template(config['hosts']['name'], template_vars)

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