Install dynamic-inventory as console_script

If you want to store openstack_deploy content you want it's content
to be relevant. However, at the moment it's quite hard to predict how
inventory will be generated if/when adding some new host to it.

Installing dynamic_inventory script as a console_script will allow you
to create quite simple tox env to update openstack_inventory.json
on local machine right after changing config and simplify life of
operator. Also this way you don't need to clone openstack-ansible

Change-Id: I6119b0bfc27d173610657f39ebb717e0a18b247e

doc/source/reference/inventory/generate-inventory.rst

@@ -2,7 +2,8 @@ Generating the Inventory
 ========================
 
 The script that creates the inventory is located at
-``inventory/dynamic_inventory.py``.
+``inventory/dynamic_inventory.py`` and installed into the ansible-runtime
+virtualenv as ``openstack-ansible-inventory``.
 
 This section explains how ansible runs the inventory, and how
 you can run it manually to see its behavior.
@@ -22,6 +23,14 @@ Run the following command:
     # from the root folder of cloned OpenStack-Ansible repository
     inventory/dynamic_inventory.py --config /etc/openstack_deploy/
 
+Dynamic inventory script is also installed inside virtualenv as a script. So
+alternatively you can run following:
+
+.. code-block:: bash
+
+    source /opt/ansible-runtime/bin/activate
+    openstack-ansible-inventory --config /etc/openstack_deploy/
+
 This invocation is useful when testing changes to the dynamic inventory script.
 
 Inputs
@@ -125,3 +134,40 @@ debugging the inventory script's behavior. The output is written to
 The ``inventory.log`` file is appended to, not overwritten.
 
 Like ``--check``, this flag is not invoked when running from ansible.
+
+
+Running with tox
+~~~~~~~~~~~~~~~~
+
+In some cases you might want to generate inventory on operator local machines
+after altering openstack_user_config.yml or env.d/conf.d files. Given that
+you already have ``openstack_deploy`` directory on such machine, you can create
+tox.ini file in that directory with following content:
+
+.. code-block::
+
+  [tox]
+  envlist = generate_inventory
+
+  [testenv]
+  skip_install = True
+  usedevelop = True
+  allowlist_externals =
+      bash
+
+  [testenv:generate_inventory]
+  basepython = python3
+  deps = -rhttps://opendev.org/openstack/openstack-ansible/raw/branch/master/requirements.txt
+  install_command =
+      pip install -c https://releases.openstack.org/constraints/upper/master {packages} git+https://opendev.org/openstack/openstack-ansible@master
+  commands =
+      osa-dynamic-inventory --config {toxinidir}
+
+Then you can run a command to generate inventory using tox:
+
+.. code-block:: bash
+
+  tox -e generate_inventory
+
+As a result you will get your openstack_user_config.json updated. You can use
+this method also to verify validity of the inventory.

inventory/dynamic_inventory.py

@@ -75,7 +75,11 @@ def args(arg_list):
     return vars(parser.parse_args(arg_list))
 
 
-if __name__ == '__main__':
+def main():
     all_args = args(sys.argv[1:])
     output = generate.main(**all_args)
     print(output)
+
+
+if __name__ == '__main__':
+    main()

setup.cfg

@@ -25,3 +25,7 @@ universal = 1
 
 [files]
 packages = osa_toolkit
+
+[entry_points]
+console_scripts =
+    openstack-ansible-inventory = inventory.dynamic_inventory:main