Lab 10 - Solution
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Mandatory
=========

Split your inventory
--------------------
* Create two inventory files for ``test`` and ``prod``
* Use the same structure, but only use one web server

    * Add ``web1.<firstname>.lab`` into ``prod``
    * Add ``web2.<firstname>.lab`` into ``test``

.. code-block:: yaml

    # file: prod
    [web]
    web1.pascal.lab

    [db]
    db.pascal.lab

.. code-block:: yaml

    # file: test
    [web]
    web2.pascal.lab

    [db]
    db.pascal.lab


* Run a ad-hoc command on the hostgroup ``web`` for both inventory files ``test`` and ``prod``
* Verify, if the task was executed on the right server

.. code-block:: bash

    # run ping on the group web in the inventory test
    ansible -m ping -i test web

    # output
    web2.pascal.lab | SUCCESS

    # run ping on the group web in the inventory prod
    ansible -m ping -i prod web

    # output
    web1.pascal.lab | SUCCESS


Set some variables
------------------
* In your ``test`` inventory, create a parent group called ``test`` and add the group ``web`` and ``db``
* In your ``prod`` inventory, create a parent group called ``prod`` and add the group ``web`` and ``db``

.. code-block:: yaml

    # file: test
    [test:children]
    web
    db

.. code-block:: yaml

    # file: prod
    [prod:children]
    web
    db

* Create a variable ``envvar: test`` only for the ``test`` servers
* Create a variable ``envvar: prod`` only for the ``prod`` servers

.. code-block:: yaml

    # file: group_vars/test.yml
    ---
    envvar: test

.. code-block:: yaml

    # file: group_vars/prod.yml
    ---
    envvar: prod


* Create a playbook ``env.yml`` and create a task to debug the ``envvar`` variable
* Run the playbook with both inventories

.. code-block:: bash

    # file: env.yml
    ---
    - hosts: all
      tasks:
        - name: debug envvar
          debug:
            msg: '{{ envvar }}'

    # run env.yml on test
    ansible-playbook -i test env.yml

    # run env.yml on prod
    ansible-playbook -i prod env.yml

Change the inventory in ansible.cfg
-----------------------------------
* Make the ``test`` inventory to your default inventory

.. code-block:: bash

    # file: ansible.cfg
    [defaults]
    inventory = test


Create a new role
-----------------
* Create a new role ``flask_app``
* Create a new group variable ``flask_app_version`` for ``test`` and ``prod``

    * value for ``prod`` -> v1.0
    * value for ``test`` -> v1.1

.. code-block:: yaml

    # file: group_vars/test.yml
    ---
    flask_app_version: v1.1

.. code-block:: yaml

    # file: group_vars/prod.yml
    ---
    flask_app_version: v1.0

* Create a role default variable for ``flask_app_version`` and set it to ``master``

.. code-block:: yaml

    # file: flask_app/defaults/main.yml
    ---
    flask_app_version: master

* Create a task to checkout the git repo (see `Git Module <http://docs.ansible.com/ansible/devel/modules/git_module.html>`_)

    * https://github.com/pstauffer/flask-mysql-app.git
    * checkout the version defined in the variable ``flask_app_version``
    * destination path should be ``/opt/flask_app``

.. code-block:: yaml

    # file: roles/flask_app/tasks/main.yml
    ---
    - name: checkout flask_app
      git:
        repo: https://github.com/pstauffer/flask-mysql-app.git
        dest: /opt/flask_app
        version: '{{ flask_app_version }}'

* Create a new playbook ``deploy.yml``

    * run only on ``web`` hostgroup
    * add the ``flask_app`` role

.. code-block:: yaml

    # file: deploy.yml
    ---
    - hosts: web
      roles:
        - flask_app

* Run the playbook on both inventories ``test`` and ``prod``

.. code-block:: bash

    # run on test
    ansible-playbook -i test deploy.yml

    # run on prod
    ansible-playbook -i prod deploy.yml

* Verify the checkout of the correct version -> Log on the servers, switch into the ``/opt/flask_app`` directory and run ``git describe --tags`` or ``git status``

.. code-block:: bash

    ssh web1.<firstname>.lab
    cd /opt/flask_app
    git describe --tags
    v1.0

    ssh web2.<firstname>.lab
    cd /opt/flask_app
    git describe --tags
    v1.1


Commit your changes
-------------------
* add all files to your git repo and commit it

.. code-block:: bash

    git status
    git add roles/*
    git commit -m 'lab 10'