Document where we are going

Somewhat opinionated document on where we want to be going, should be
an accurate first approximation of what Dean and I have chatted about
over the last few weeks. Hopefully helpful in framing where we are
going.

Change-Id: Ia153af27a08203ffc44e37c7db73e04573d3be9f

FUTURE.rst

@@ -0,0 +1,113 @@
+=============
+ Quo Vadimus
+=============
+
+Where are we going?
+
+This is a document in Devstack to outline where we are headed in the
+future. The future might be near or far, but this is where we'd like
+to be.
+
+This is intended to help people contribute, because it will be a
+little clearer if a contribution takes us closer to or further away to
+our end game.
+
+==================
+ Default Services
+==================
+
+Devstack is designed as a development environment first. There are a
+lot of ways to compose the OpenStack services, but we do need one
+default.
+
+That should be the Compute Layer (currently Glance + Nova + Cinder +
+Neutron Core (not advanced services) + Keystone). It should be the
+base building block going forward, and the introduction point of
+people to OpenStack via Devstack.
+
+================
+ Service Howtos
+================
+
+Starting from the base building block all services included in
+OpenStack should have an overview page in the Devstack
+documentation. That should include the following:
+
+- A helpful high level overview of that service
+- What it depends on (both other OpenStack services and other system
+  components)
+- What new daemons are needed to be started, including where they
+  should live
+
+This provides a map for people doing multinode testing to understand
+what portions are control plane, which should live on worker nodes.
+
+Service how to pages will start with an ugly "This team has provided
+no information about this service" until someone does.
+
+===================
+ Included Services
+===================
+
+Devstack doesn't need to eat the world. Given the existence of the
+external devstack plugin architecture, the future direction is to move
+the bulk of the support code out of devstack itself and into external
+plugins.
+
+This will also promote a more clean separation between services.
+
+=============================
+ Included Backends / Drivers
+=============================
+
+Upstream Devstack should only include Open Source backends / drivers,
+it's intent is for Open Source development of OpenStack. Proprietary
+drivers should be supported via external plugins.
+
+Just being Open Source doesn't mean it should be in upstream Devstack
+if it's not required for base development of OpenStack
+components. When in doubt, external plugins should be used.
+
+========================================
+ OpenStack Services vs. System Services
+========================================
+
+ENABLED_SERVICES is currently entirely too overloaded. We should have
+a separation of actual OpenStack services that you have to run (n-cpu,
+g-api) and required backends like mysql and rabbitmq.
+
+===========================
+ Splitting up of Functions
+===========================
+
+The functions-common file has grown over time, and needs to be split
+up into smaller libraries that handle specific domains.
+
+======================
+ Testing of Functions
+======================
+
+Every function in a functions file should get tests. The devstack
+testing framework is young, but we do have some unit tests for the
+tree, and those should be enhanced.
+
+==============================
+ Not Co-Gating with the World
+==============================
+
+As projects spin up functional test jobs, Devstack should not be
+co-gated with every single one of those. The Devstack team has one of
+the fastest turn arounds for blocking bugs of any Open Stack
+project.
+
+Basic service validation should be included as part of Devstack
+installation to mitigate this.
+
+============================
+ Documenting all the things
+============================
+
+Devstack started off as an explanation as much as an install
+script. We would love contributions to that further enhance the
+comments and explanations about what is happening, even if it seems a
+little pedantic at times.