[UPlat] Resource Lifecycle

[Heather Kreger <kreger@us.ibm.com>]

Here is the reworked lifecycle definition that should stay in the platform
list. Upon exploring this space a little more, I'd like to call it Resource
Lifecycle. Because The lifecycle of a Web service is characterized by its
deployment at a service endpoint; a service is said to be created when it
is deployed and destroyed when it is undeployed.

1.1.1 Resource LifeCycle
1.1.1.1     What?

The lifecycle of a Web service is characterized by its deployment at a
service endpoint; a service is said to be created when it is deployed and
destroyed when it is undeployed.


The lifecycle of a resource may be created or deployed to the system and
remain in the system in a permanent or semi-permanent unless it is
destroyed unintentionally by a hardware or software failure, or
intentionally by a manager. Some resources are more temporal in nature;
instances are created and destroyed more frequently, where its lifecycle is
defined as that period between its instantiation (which may occur through
use of a Web service acting as a resource factory) and its destruction.


For temporary resources, it is necessary to define a standard way to
understand how to create the resource, i.e. identify its factory or
constructor methodology and identify its destruction methodology.

1.1.1.2     Why?

1. Client interest in the resource: Normally, a requestor’s interest in a
resource is for some period of time, rarely is it indefinite. In many
scenarios, it is appropriate for clients of a resource to explicitly
destroy it. In a distributed computing environment, a user may become
disconnected from the service provider’s endpoint and therefore may be
unable to, or unwilling to explicitly destroy the resource. A client of a
resource may establish and renew its interest in the resource for a
specific period of time. If that time expires, the resource may “self
destruct” without the need for an explicit destroy request from a client.
Periodically renewing interest in a resource can serve to extend its
lifetime.


2. Provisioning applications: Resource virtualization, where generic, or
virtual, resources are managed and mapped onto physical resources by the
runtime, creates a scenario where the generic resources will have temporary
lifetimes. Provisioning applications managing these virtual resources will
need to be able to create new resources and destroy these resources.

1.1.1.3     How?

Suggestion, a specification based on OGSI 1.0 specification: A
specification defining a canonical way to identify a factory pattern for
resource creation (factory service for resource’s manageability endpoint)
and resource destruction (explicit destruction, implicit destruction, i.e.
lease, timeouts)

Heather Kreger
STSM, Web Services Lead Architect for SWG Emerging Technologies
Author of "Java and JMX: Building Manageable Systems"
kreger@us.ibm.com
919-543-3211 (t/l 441)  cell:919-496-9572