Open Stack

Hi,

In moving repos to OpenDev and a gitea instance [1] we will need to
change any git://git.openstack.org references to https://, as gitea
does not currently support the native git protocol.

First up, from a "gate on fire" point of view, the sky is not falling.
Most jobs referencing git repos should be using the local Zuul
repositories during their gate CI, and not pulling directly from git.
This should minimise issues.  Still, we need to fix things up.

Some raw numbers: to simply perform a
"s|git://git.openstack.org|https://git.openstack.org|" over every
openstack/* repository on master and every stable/* branch inside
results in ~1200 changes [2].  If we limit that just to projects with
a devstack plugin (I would say the main user of git:// urls as every
plugin has more or less copied it this way) that's about 420 changes.
If you'd like to try it yourself, scripts are at [3].  I can't really
categorise this; there's a lot of documentation updates, a lot of
devstack plugin changes, a bunch of -1/+1 changes and some weirder
ones with manifest files, etc.

There was discussion over this in the infra meeting [5].  I think we
came up with 3 options:


1. Propose changes now
----------------------

We can propose all these changes to the gate now (slowly, but
ultimately in one hit) and let teams review and merge them.

Pros:

 * changes are tested
 * we get this done _before_ the transition; meaning one less thing
 * teams get a heads up, can call out anything odd

Cons:

 * sure to be a lot of unrelated gate failures
 * sure to be a lot of unmerged changes
 * experience has shown that mass changes can cause confusion.  Things
   happen like others then proposing similar changes or otherwise
   getting the wrong idea about what is happening.
 * Ultimately will still be using redirects from openstack.org to
   opendev.org after transition


2. Merge changes at transition time
-----------------------------------

We can have the same changes ready to go, and merge them manually
during the transition maintenance period to gitea; bypassing the gate.

Pros:

 * avoids cons of 1

Cons:

 * one more thing to do during a tricky transition
 * changes aren't tested.  This is a very low risk change; but
   we all know the xkcd about breaking people's workflows [4]
 * Ultimately will still be using redirects from openstack.org to
   opendev.org after transition


3. Merge changes at transition time, with full rename
-----------------------------------------------------

Similar to 2, but by timing such that OpenDev gitea will be fully
operational we can modify the changes such that they go directly to
the OpenDev namespace.  This is a more tricky change, essentially

 (https|git)://git.openstack.org/openstack/project ->
   https://git.opendev.org/openstack/project

Pros:

 * Pros of 2.
 * This moves directly to the "final state"

Cons:

 * Cons of 2.
 * Adds another match, which increases again the risk that things break
   with the new URLs (internal regex matches, etc).
 * The "openstack/project" part of the name is, I believe, still under
   discussion over exactly how we will lay that out, and if projects
   may have their own namespaces, etc.  Adds a synchronization point
   with this; possible complexity.

My personal feeling here is that we have enough to do with the
transition, and we would be better to sort this out as much as
possible first.  Thus I'd suggest we take approach 1 of submitting
changes to the gate now.  I imagine active projects will appreciate
the heads up and merge things quickly.  However, given the low risk,
I'd suggest we agree on a date to force-merge any outstanding reviews
before the cut over.  This leaves us relying on the redirects from
openstack.org -> opendev.org, but practically there is no way we can
avoid having those in place anyway (due to external links), so cleanup
of that can be handled by projects asynchronously.

Of course, opinions welcome :) I'd suggest we make a concrete decision
in the next infra meeting.

-i

[1] http://lists.openstack.org/pipermail/openstack-discuss/2019-March/003603.html
[2] http://paste.openstack.org/show/747762/
[3] https://review.openstack.org/642314
[4] https://xkcd.com/1172/
[5] http://eavesdrop.openstack.org/meetings/infra/2019/infra.2019-03-12-19.01.log.html#l-241