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On 08/19/2015 02:05 AM, Ruby Loo wrote:
>
>
>
>         On 17 August 2015 at 20:20, Robert Collins
>         <robertc at robertcollins.net <mailto:robertc at robertcollins.net>>
>         wrote:
>
>             On 11 August 2015 at 06:13, Ruby Loo <rlooyahoo at gmail.com
>             <mailto: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 :)

Again...

>
> 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).

And I want node to be created in INSPECTING state directly. I don't care 
it's a transient state, I just want it :) Oh, and can I please skip 
MANAGEABLE? I need the following flow INSPECTING->AVAILABLE.

Now seriously: to what degree are we going to allow people to break our 
state machine? Or alternatively, are we going to allow steps to happen 
automatically? I'm in favor of this idea actually, maybe someone feels 
like writing a spec?

>
> 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
> ?

B. No more breaking changes please.

>
>
> 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

A sounds nice, but that's now how our state machine currently works. 
Being able to skip states is really an interesting feature, but it 
requires somewhat broader discussion. And then yes, you should allow me 
to just straight into INSPECTING in this case :)

If it's not implied, then my vote is:
D. don't do it

>
> 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.

And I get bug reports like "inspector does not work". Sigh...

>
> 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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