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>> On 17 August 2015 at 20:20, Robert Collins <robertc at robertcollins.net>
>> wrote:
>>
>>> On 11 August 2015 at 06:13, Ruby Loo <rlooyahoo at gmail.com> wrote:
>>> > Hi, sorry for the delay. I vote no. I understand the rationale of
>>> trying to
>>> > do things so that we don't break our users but that's what the
>>> versioning is
>>> > meant for and more importantly -- I think adding the ENROLL state is
>>> fairly
>>> > important wrt the lifecycle of a node. I don't particularly want to
>>> hide
>>> > that and/or let folks opt out of it in the long term.
>>> >
>>> > From a reviewer point-of-view, my concern is me trying to remember all
>>> the
>>> > possible permutations/states etc that are possible to make sure that
>>> new
>>> > code doesn't break existing behavior. I haven't thought out whether
>>> adding
>>> > this new API would make that worse or not, but then, I don't really
>>> want to
>>> > have to think about it. So KISS as much as we can! :)
>>>
>>> I'm a little surprised by this, to be honest.
>>>
>>> Here's why: allowing the initial state to be chosen from
>>> ENROLL/AVAILABLE from the latest version of the API is precisely as
>>> complex as allowing two versions of the API {old, new} where old
>>> creates nodes in  AVAILABLE and new creates nodes in ENROLL. The only
>>> difference I can see is that eventually someday if {old} stops being
>>> supported, then and only then we can go through the code and clean
>>> things up.
>>>
>>> It seems to me that the costs to us of supporting graceful transitions
>>> for users here are:
>>>
>>> 1) A new version NEWVER of the API that supports node state being one
>>> of {not supplied, AVAILABLE, ENROLL}, on creation, defaulting to
>>> AVAILABLE when not supplied.
>>> 2) Supporting the initial state of AVAILABLE indefinitely rather than
>>> just until we *delete* version 1.10.
>>> 3) CD deployments that had rolled forward to 1.11 will need to add the
>>> state parameter to their scripts to move forward to NEWVER.
>>> 4) Don't default the client to the veresions between 1.10 and NEWVER
>>> versions at any point.
>>>
>>> That seems like a very small price to pay on our side, and the
>>> benefits for users are that they can opt into the new functionality
>>> when they are ready.
>>>
>>> -Rob
>>
>>
After thinking about this some more, I'm not actually going to address
Rob's points above. What I want to do is go back and discuss... what do
people think about having an API that allows the initial provision state to
be specified, for a node that is created in Ironic. I'm assuming that
enroll state exists :)

Earlier today on IRC, Devananda mentioned that "there's a very strong case
for allowing a node to be created in any of the stable states (enroll,
manageable, available, active)". Maybe he'll elaborate later on this. I
know that there's a use case where there is a desire to import nodes (with
instances on them) from another system into ironic, and have them be active
right away. (They don't want the nodes to go from
enroll->verifying->manageable->cleaning!!!->available!!!->active).

1. What would the default provision state be, if it wasn't specified?
A. 'available' to be backwards compatible with pre-v1.11
or
B. 'enroll' to be consistent with v1.11+
or
?


2. What would it mean to set the initial provision state to something other
than 'enroll'?

manageable
----------------
In our state machinery[0], a node goes from enroll -> verifying ->
manageable. For manageble to be initial state, does it mean that
A. whatever is needed for enroll and verifying is done and succeeds (under
the hood)
or
B. whatever is needed for enroll is done and succeeds (but no verifying)
or
C. no enroll or verifying is done, it goes straight to manageble

I'm fine with A.I'm not sure that B makes sense and I definitely don't
think C makes sense. To date, verifying means checking that the conductor
can get the power state on the node, to verify the supplied power
credentials. I don't think it is a big deal if we skip this step; it just
means that the next time some action is taken on the node, it might fail.

available
------------
In our state machinery, a node goes from enroll -> verifying -> manageable
-> cleaning -> available. For available to be initial state, does it mean
that
A. whatever is needed for enroll, verifying, cleaning is done and succeeds
(under the hood)
or
B. whatever is needed for enroll is done and succeeds (but no verifying or
cleaning)
or
??

active
--------
In our state machinery, a node goes from enroll -> verifying -> manageable
-> cleaning -> available->deploying->active. For active to be initial
state, does it mean that
A. whatever is needed for enroll, verifying, cleaning, deploying is done
and succeeds (under the hood)
or
B. whatever is needed for enroll is done and succeeds (but no verifying or
cleaning)
or
C. whatever is needed for enroll and I dunno, any 'takeover' stuff by
conductor or whatever node states need to be updated to be in active?

--ruby

[0] http://docs.openstack.org/developer/ironic/dev/states.html
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