Merge "Spec to refactor puppet code in openstack_project"

specs/server_base_template_refactor.rst

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+::
+  Copyright 2014 Hewlett-Packard Development Company, L.P.
+
+  This work is licensed under a Creative Commons Attribution 3.0
+  Unported License.
+  http://creativecommons.org/licenses/by/3.0/legalcode
+
+
+
+==================================================
+Refactor openstack_project::{server,base,template}
+==================================================
+
+Problem Description
+===================
+
+Right now there are three 'main' classes in puppet. They are
+
+openstack_project::server
+openstack_project::base
+openstack_project::template
+
+All three of these control resources that matter to most systems.  Server
+contains template, template contains base. Then usually an application
+has a class that wraps server.
+
+The problem with this is that if you want to make a change to a resource
+that is controlled in base, parameters must be added to allow you pass in
+changes to the application class, then to the server class, then to the
+template class, finally picking it up again in the base class.
+
+
+Storyboard Link
+===============
+
+https://storyboard.openstack.org/#!/story/2000172
+
+
+Proposed Change
+===============
+
+I propose we flatten server, base, and template to a single class called
+server. All the parameters can be flattened as well, and if statements added
+to allow someone or something who really wanted 'template' to get just those
+resoruces. (nodepool prepare node jumps directly into template, its the only
+place I've found so far that base or template are called directly)
+
+Additionally I propose we pull the openstack_project::server invocation
+out of the application classes and put it in the node definition. Example:
+
+.. code-block:: puppet
+
+    node 'review.openstack.org' {
+      class { 'openstack_project::server':
+        iptables_tcp_public_ports => [80, 443, 29418],
+        sysadmins                 => hiera('sysadmins', 'default'),
+      }
+      class {'openstack_project::review':
+        ... other params ..
+      }
+    }
+
+
+When every node in the environment takes the same openstack_project::server
+class, that means that the differences between two nodes can be thought of
+as the array of parameters passed into those servers. It makes servers more
+like each other and easier to reason about. It also frees the application
+class to do what it does best, which is set up the application. o_p::server
+handles all the base configuration and o_p::application handles the application.
+
+Alternatives
+------------
+
+We could remain the same. We could flatten server, base, and template without
+pulling the openstack_project::server invocation out of the application class.
+
+Implementation
+==============
+
+Server class would be expanded to include the parameters and resources
+of base class and template class. New parameters would be added so that
+there is a way to get just the resources of template and base.
+
+Application classes would be modified to not need server class, site.pp
+would be modified.
+
+
+Assignee(s)
+-----------
+
+Primary assignee:
+  nibalizer
+
+
+Work Items
+----------
+
+* base.pp flatten
+* template.pp flatten
+* refactor of places where those classes are used
+* refactor of server.pp
+* application specific refactors + site.pp changes
+
+
+Repositories
+------------
+
+No new git repos
+
+Servers
+-------
+
+Puppet change only
+
+DNS Entries
+-----------
+
+Puppet change only
+
+Documentation
+-------------
+
+Largely should be transparent to anyone who isn't mucking around in
+infra internals
+
+Security
+--------
+
+No security implications
+
+Testing
+-------
+
+apply-test will provide acceptance testing
+
+Dependencies
+============
+
+No known dependencies
+
+
+
+
+