Could we discuss the identification
attributes for a minute, because I think that sets the stage for the
discussion of state attributes?
In the email that teed this all up, I
wrote:
>
> To
identify the account, Account has "target", "name",
> and "guid" attributes. The account is usually
associated
> with some target, has a name that is changeable,
and
> may have an internal identifier
> that
is not supposed to change.
>
When I say "Account", I think of this as
roughly equivalent to "ProvisionedObject". (I realize that not all
features of Account apply to every provisioned object, but this
doesn't bother me too much because not all features of Account apply to
every account. Target accounts all different, but there
are also common features.)
Not every target supports "guid", but it's
common enough (especially among the modern targets) that it's reasonable
to model this as a common feature. We can simply leave "guid" null
or empty where it is unknown or unsupported.
I don't want to leave this
"open" (i.e., an entirely arbitrary
attribute) because guid is pretty common and very useful in
managing the account. Where guid is supported, it is the preferred
identifier. It is *very* handy to keep a guid as a native
identifier, since this helps in detecting native renames (and
distinguishing a 'move' from a 'delete' and an 'add'). Where the
target supports some kind of guid, I want to map that value to an
attribute that my management code recognizes.
I'm guessing that everybody basically buys
this premise, because the discussion has centered on the state-related
attributes. Here's the part where I step off the
ledge...
I think of the state-related attributes we've
been discussing in the same way: common and useful where supported,
harmless and empty if unsupported. For example, it doesn't bother me at all if a particular class of
provisioned object doesn't support "disabled", as long as the value that
comes back is harmless (e.g., empty or "NOT_SUPPORTED").
It's common enough (not just for
accounts, but also for policies and other objects) to add
objects disabled and then enable them at a later date. This is
such a common aspect of management that I'd prefer to model this explictly
as a well-known aspect of state.
I'm interested to know what everyone
thinks. I'm not sure everyone will agree with this line of
reasoning, but if this explains where I'm coming from, then maybe you all
can use it to explain things to me.
Gary
----- Original Message -----
Sent: Friday, March 26, 2004 9:32
AM
Subject: Re: [provision]
PSO/Account/ProvisionedState
This sounds
interesting. Defining multiple interfaces (as Gerry suggests)
sounds like a reasonable way to tease apart the facets that interest
some (but not necessarily all) of us. Tying these to a common
schema (as Jeff B suggests) seems like a reasonable way to keep the
whole thing from flying apart.
I need a little more help
imagining how we'd structure this. I wanted to define a bunch
of common state-related attributes, but Jeff B and others point out that
not all of these apply to all types of accounts. Perhaps none of
these state-related attributes (beyond "exists") apply to some kinds of
provisioned object.
I had imagined calling a method
like:
State
getProvisionedState(PSO-ID);
For an Account, I'd get back all the
attributes that apply:
<State psoId='ID'
exists='true' disabled='false' disableDate='NONE' enableDate='NONE'
expired='false' expireDate='DATE' />
For a provisioned object that supports only
"exists", I'd get back only "exists":
<State psoId='ID'
exists='true'/>
But it sounds to me from the discussion
above, that I might have to define a different schema for each
combination of attributes. Am I right about that, or could
'Stateful' contain our "starter kit" of common state-related
attributes?
Would each kind of provisioned object
have to define in its schema which state-related attributes it supports?
Or would I just call a different method
(e.g., #listSupportedStateAttributes)?
Or could I figure this out just from
the set of attributes returned by
#getProvisionedState(PSO-ID)?
Sorry if I'm misunderstanding
your suggestion. If so,
perhaps we should talk offline (rather than email
everyone).
Gary
----- Original Message -----
Sent: Thursday, March 25, 2004
7:51 PM
Subject: RE: [provision]
PSO/Account/ProvisionedState
I would not be opposed to having mulitple provisioning
interfaces, provided it was tied to a standard schema that normatively
defined what interfaces where appropriate for what object classes. The
clients still need to know what interfaces would apply to what
PSOs.
For example the SPML core operations could apply to all object
classes but the SPML state operations may only apply to an object
class that inherits from a "Stateful" object class in a standard
schema (note that SPML 1.0 supports multiple inheritance so this is
easy). This way the schema for the resource does not even need to
extend an abitrary "Account" schema, it merely needs to extend
the "Stateful" schema.
Jeff Bohren
OpenNetwork
-----Original Message-----
From:
Gearard Woods [mailto:gewoods@us.ibm.com]
Sent: Thu
3/25/2004 6:01 PM
To: Jeff Larson
Cc: Gary
Cole; Jeff Bohren; provision@lists.oasis-open.org
Subject: RE: [provision]
PSO/Account/ProvisionedState
I agree that granularity of the calls is important and it really
shouldn't take 42 calls to determine the state of an object - a
single call should suffice. I think we can model state effectively
and still minimize the traffic needed to manage it.
Jeff
(Jeff B) has also raised the slippery slope argument, and my take on
it is that we should provide an interoperable way to do the things
we feel are a core part of the provisioning process. There is a line
here between what is horizontal to provisioning and what is
resource-specific. State management is obviously important and
passwords have come up before, although Jeff B would argue that
state is not even relevant to most resources and is only applicable
to accounts.
The provisioning process is obviously not the
same thing to all people. We have disagreement even down to the
fundamentals of the provisioning model. Perhaps a way to tackle
these different viewpoints is to divide and conquer. Imagine that we
split up the problem into a number of interfaces:
SPML core -
Basic provision (add), deprovision (delete), modify,
list/search
SPML state - An interface and schema representing
state management (lifecycle included or separate?)
SPML events -
An interface and schema for event notifications
SPML password -
Password management perhaps
SPML relationships -
TBD
Implementors must publish core to be SPML compliant. They
may then in turn overlay any of the other interfaces to offer
enhanced provisioning capabilities. These would be simple interfaces
with minimal schema but would be complementary and all take
advantage of the core schema. Vendors who deal with directory-style
interfaces need go no further than the core interface while others
may wish to offer the full suite. Obviously these categories are
just off the top of my head but does this sound like an approach
that has promise?
Gerry
"Jeff Larson"
<Jeff.Larson@waveset.com>
I haven't been following this that closely,
but I like aspects of both approaches. I like
the notion that you can carry out
near-universal operations like disable, enable, and expire,
in a schema independent
way. But I also like the notion that I can at least obtain the
current state
from the
model so I don't have to make 42 web services calls to get
everything I want to display.
I guess as long as
the schema is arbitrary we can have it both ways. If I
choose
to use fine grained
standard operations I can. If the PSP exposes the same
functionality
through the
model, I can use that too, though I will be outside of the SPML
spec.
But we're on a slippery slope here. Almost every
account will have an associated
password, email address, and full name. Do we then
provide individual operations
to get and set those so we can access them in an
standard way without having to be
bothered with PSP specific schema? How far does this
go?
Jeff
-----Original Message-----
From: Gearard Woods [mailto:gewoods@us.ibm.com]
Sent:
Thursday, March 25, 2004 3:35 PM
To: Jeff
Bohren
Cc: Gary Cole;
provision@lists.oasis-open.org
Subject: RE:
[provision] PSO/Account/ProvisionedState
I think there's a fundamental difference here even
though the intent may be the same. Basically, we're all trying to
model state and provide some kind of standardized view of it to the
outside world so that we can offer interoperability. By placing
state in the resource schema you have immediately abandoned the
possibility that arbitrary resource schema may be supported, which I
believe to be important. You are also now requiring a mapping from
the "standard" schema to the real resource schema. On the other
hand, by placing the emphasis on the service provider and providing
an operational interface to effect state changes, the provider can
now apply its knowledge of the resource to make the state change
however it wishes to do so and places no restrictions on the
resource schema.
Gerry
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