.. _development:

Development
===========

This section covers procedures and information related to development of *Majic
Ansible Roles*.


Preparing environment
---------------------

The easiest way to get going with role development is to set-up a separate
Python virtual environment with the necessary packages. This can be done by
performing the following steps:

1. Ensure that the following minimum set of packages are installed via
   distribution package manager:

   - `Git <https://git-scm.com/>`_
   - `libffi <https://sourceware.org/libffi/>`_ runtime and development package.
   - `OpenSSL <https://www.openssl.org/>`_ runtime and development package.
   - `pip <https://pypi.python.org/pypi/pip/>`_
   - `virtualenv <https://pypi.python.org/pypi/virtualenv>`_
   - `virtualenvwrapper <https://virtualenvwrapper.readthedocs.io/en/latest/>`_
   - Development packages for Python.

   On Debian this can be easily done with::

     apt-get install virtualenv virtualenvwrapper git python-pip python-dev \
     libffi-dev libssl-dev

2. In order to be able to run role tests, it is necessary to install `VirtualBox
   <https://www.virtualbox.org/>`_ and `Vagrant <https://www.vagrantup.com/>`_,
   using instructions outlined on their respective websites. It is recommended
   to use latest versions available. At time of this writing the role tests have
   been successfully run on *VirtualBox 5.1.22* and *Vagrant 1.9.5*.

3. Clone the git repository::

     git clone https://code.majic.rs/majic-ansible-roles/ ~/projects/

4. Create a separate Python virtual environment::

     mkvirtualenv majic-ansible-roles -a ~/projects/majic-ansible-roles/

5. Make sure the virtual environment has been activated, and install `pip-tools
   <https://github.com/jazzband/pip-tools>`_::

     workon majic-ansible-roles
     pip install pip-tools

6. Synchronise Python virtual environment with requirements file using
   **pip-tools**::

     workon majic-ansible-roles
     pip-sync


Running role tests
------------------

Role tests are implemented using `Molecule <https://molecule.readthedocs.io/>`_,
`Testinfra <https://testinfra.readthedocs.io/en/latest/>`_, `VirtualBox
<https://www.virtualbox.org/>`_ and `Vagrant
<https://www.vagrantup.com/>`_. *Molecule* and *Testinfra* are installed inside
of Pyhton virtual environment, while *VirtualBox* and *Vagrant* need to be
installed distribution-wide, following instructions outlined on their
corresponding websites.

In order to run tests for a specific role, perform the following steps:

1. Switch to Python virtual environment::

     workon majic-ansible-roles

2. Change directory::

     cd roles/ROLENAME/

3. List available supported platforms::

     molecule list

4. Run tests for default platform (Debian Jessie)::

     molecule test

5. Run tests for Debian Stretch (if role tests support it)::

     molecule test --platform debian-stretch64


.. _testsite:

Test Site
---------

*Majic Ansible Roles* comes with a small sample test site configuration which
demonstrates use of every role. This test site also serves as starting point for
developing new roles etc, and can be used for testing regressions/breakages.

The test site covers everything, starting from generating the Debian preseed
files, through bootstrap process for new nodes, and onto deployment of all
remaining roles.

By default, the test site uses domain ``example.com``, but it has been designed
so it is easy to set your own domain (see below in step-by-step
instructions). Some changes may be necessary to listed commands in that case
(i.e. replace every occurance of ``example.com`` with your own domain).

All example commands listed within this section should be ran from within the
``testsite`` directory in order to have proper environment available for
playbook runs.

A number of playbooks is provided out of the box:

bootstrap.yml (for bootstrapping fresh nodes)
  This playbook can be used for bootstrapping fresh nodes. By default, the
  entire test site will be included in the bootstrap. If you wish to limit
  bootstrap to a single server, just run the playbook with (for example):

  .. code-block:: shell

    ansible-playbook -l ldap.example.com playbooks/bootstrap.yml

ldap.yml
  This playbook sets-up the LDAP servers. It is included in ``site.yml``.

mail.yml
  This playbook sets-up the mail server. It is included in ``site.yml``.

preseed.yml
  This playbook sets-up the Debian preseed files. It is included in
  ``site.yml``.

site.yml
  This playbook sets-up all servers, including preseed files on local host.

web.yml
  This playbook sets-up the web server. It is included in ``site.yml``.

xmpp.yml
  This playbook sets-up the XMPP server. It is included in ``site.yml``.

backup.yml
  This playbook sets-up the backup server. It is included in ``site.yml``.

In order to deploy the test site, the following steps would normally be taken:

1. As mentioned in introduction, default domain used by test site is
   ``example.com``. To change it, perform the following steps (otherwise, just
   skip to step 2):

   a. Update the file ``hosts``. Simply replace all occurances of
      ``example.com`` with your chosen domain.
   b. Update the file ``group_vars/all.yml``, changing the value of variable
      ``testsite_domain``. This value will then be used to calculate some of
      derived values, like LDAP base DN (which will be set to something along
      the lines of ``dc=example,dc=com`` or
      ``dc=your,dc=domain,dc=components``).

2. If you do not wish to have the hassle of creating the private keys and
   issuing certificates, there is a small playbook that can help you with
   this. Just run the ``tls.yml`` playbook, and skip to step 6 (otherwise follow
   steps 3 through 5):

   .. code-block:: shell

     ansible-playbook playbooks/tls.yml

3. Create TLS private keys (relative to top level directory), making sure to
   change domain in filenames if necessary:

   - ``testsite/tls/mail.example.com_imap.key``
   - ``testsite/tls/mail.example.com_smtp.key``
   - ``testsite/tls/xmpp.example.com_xmpp.key``
   - ``testsite/tls/ldap.example.com_ldap.key``
   - ``testsite/tls/web.example.com_https.key``
   - ``testsite/tls/phpfino.example.com_https.key``
   - ``testsite/tls/wsgi.example.com_https.key``
   - ``testsite/tls/wsgireq.example.com_https.key``

4. Issue TLS certificates corresponding to the generated TLS private keys
   (correct FQDN for DNS subject alternative name **must** be used), making sure
   to change domain in filenames if necessary:

   - ``testsite/tls/mail.example.com_imap.pem`` (subject alternative name should
     be ``mail.example.com``)
   - ``testsite/tls/mail.example.com_smtp.pem`` (subject alternative name should
     be ``mail.example.com``)
   - ``testsite/tls/xmpp.example.com_xmpp.pem`` (subject alternative name should
     be ``xmpp.example.com``)
   - ``testsite/tls/ldap.example.com_ldap.pem`` (subject alternative name should
     be ``ldap.example.com``)
   - ``testsite/tls/web.example.com_https.pem`` (subject alternative name should
     be ``web.example.com``)
   - ``testsite/tls/web.example.com_https.pem`` (subject alternative name should
     be ``web.example.com``)
   - ``testsite/tls/phpinfo.example.com_https.pem`` (subject alternative name
     should be ``phpinfo.example.com``)
   - ``testsite/tls/wsgi.example.com_https.pem`` (subject alternative name
     should be ``wsgi.example.com``)
   - ``testsite/tls/wsgireq.example.com_https.pem`` (subject alternative name
     should be ``wsgireq.example.com``)

5. Create ``PEM`` truststore file which contains all CA certificates that form
   CA chain for the issued end entity certificates from previous step at
   location ``testsite/tls/ca.pem``. It is very important to
   include the full CA chain used for LDAP server.

6. Generate SSH keys to be used by the backup server and backup clients:

  .. code-block:: shell

     mkdir ssh
     ssh-keygen -f ssh/backup_server_dsa_key -N '' -t dsa
     ssh-keygen -f ssh/backup_server_rsa_key -N '' -t rsa
     ssh-keygen -f ssh/backup_server_ed25519_key -N '' -t ed25519
     ssh-keygen -f ssh/backup_server_ecdsa_key -N '' -t ecdsa
     ssh-keygen -f ssh/mail.example.com -N ''
     ssh-keygen -f ssh/ldap.example.com -N ''
     ssh-keygen -f ssh/xmpp.example.com -N ''
     ssh-keygen -f ssh/web.example.com -N ''
     ssh-keygen -f ssh/backup.example.com -N ''
     ssh-keygen -f ssh/ws01.example.com -N ''

7. Set-up a local GnuPG keyring that will contain the necessary encryption and
   signing keys for the backup clients::

     mkdir ./backup_keyring
     chmod 700 ./backup_keyring
     cat << EOF | gpg2 --homedir ./backup_keyring --batch --gen-key
     Key-Type:RSA
     Key-Length:1024
     Name-Real:ldap.example.com
     Expire-Date:0
     %no-protection
     %commit

     Key-Type:RSA
     Key-Length:1024
     Name-Real:mail.example.com
     Expire-Date:0
     %no-protection
     %commit

     Key-Type:RSA
     Key-Length:1024
     Name-Real:web.example.com
     Expire-Date:0
     %no-protection
     %commit

     Key-Type:RSA
     Key-Length:1024
     Name-Real:xmpp.example.com
     Expire-Date:0
     %no-protection
     %commit

     Key-Type:RSA
     Key-Length:1024
     Name-Real:backup.example.com
     Expire-Date:0
     %no-protection
     %commit

     Key-Type:RSA
     Key-Length:1024
     Name-Real:ws01.example.com
     Expire-Date:0
     %no-protection
     %commit
     EOF

8. Generate the preseed files:

  .. code-block:: shell

     ansible-playbook playbooks/preseed.yml

9. Install all servers using the generated preseed files. All servers except
   ``ws01.example.com`` are supposed to be running *Debian 8 Jessie*. The server
   ``ws01.example.com`` is meant to run *Debian 9 Stretch* (althogh, Debian
   Jessie should function as well).

10. Add the SSH host fingerprints to your ``known_hosts`` file (don't forget to
    remove old entries if you are redoing the process). You can easily obtain all
    the necessary fingerprints with command (don't forget to modify domain if you
    need to):

    .. code-block:: shell

      ssh-keyscan -t ed25519 mail.example.com ldap.example.com xmpp.example.com web.example.com backup.example.com ws01.example.com $(resolveip -s mail.example.com) $(resolveip -s ldap.example.com) $(resolveip -s xmpp.example.com) $(resolveip -s web.example.com) $(resolveip -s backup.example.com) $(resolveip -s ws01.example.com)

11. Invoke the ``bootstrap.yml`` playbook in order to set-up some basic
    environment for Ansible runs on all servers:

    .. code-block:: shell

       ansible-playbook playbooks/bootstrap.yml

12. Finally, apply configuration on all servers:

    .. code-block:: shell

       ansible-playbook playbooks/site.yml

The playbooks and configurations for test site make a couple of assumptions:

* Each server will be set-up with an operating system user ``admin``, capable of
  running the sudo commands.
* The password for operating system user ``admin`` is hard-coded to ``admin``.
* An SSH ``authorized_keys`` file is set-up for the operating system user
  ``admin``. The SSH key stored in it will be read from location
  ``~/.ssh/id_rsa.pub`` (i.e. from home directory of user running the Ansible
  commands).

For more details on how the playbooks and configuration have been implemented,
feel free to browse the test site files (in directory ``testsite``).