Title: Message
Igor,
I
think there is another discovery scenario. A manager somehow discovers WSDL
(maybe through UDDI, maybe not) for a manageability endpoint. This WSDL might
not have any functional interfaces or endpoints described, and might not even
have a reference to WSDL for the functional endpoint being managed. This will
work as long as the manageability interfaces include a reference to the
functional endpoint/service access point/message sink/???.
I
think it is important to be able to present a functional interface without
including any manageability interfaces. You may want to expose the functional
WSDL to partners and customers without exposing the manageability
WSDL.
A
reason to allow manageability WSDL to not include a reference to functional WSDL
is that the manageability endpoint may not even be aware of what resource it is
providing the manageability interface for until runtime. It could be a
configuration property.
Bryan
-----Original Message-----
From: Sedukhin, Igor S
[mailto:]
Sent: Thursday, December 11, 2003
9:24 AM
To: WSDM TC
Subject: [wsdm] Discovery of
manageability endpoint
The next obvious problem that we
need to solve for the interop scenario discussed at the F2F is: given the
functional endpoint (service) WSDL find the manageability endpoint(s). I
propose that we discuss and allow ALL of the following possible solutions,
however pick one for the interop event show run.
Possible ways to discover
manageability endpoint
1. description of the
manageability service (possibly with a set of manageability endpoints) is
embedded in the same WSDL along with functional service with its endpoint(s).
The manager detects manageability service/endpoints by verifying the operation
signatures (WSDL 1.1) or interface extension tree (WSDL
2.0).
2. The functional endpoint is ALSO
a manageability endpoint (i.e. implements functional and WSDM operations). In
this case manager has no confusion and issues management related requests to
the same endpoint that functional requests are issued to. The precise
implementation of such could be in the same code; the container that adds
management operations at the deployment time automatically; an intermediary
that appends manageability operations, sits in the message path and takes care
of management requests on behalf of the functional endpoint;
etc.
3. Both functional and
manageability endpoints are published into the same UDDI. For every service
binding (UDDI) an instance info contains a set of tModels each with a pointer
to an overview document (WSDL). There could be (and usually are) multiple
tModels for a given UDDI binding. First instance info tModels has to be
describing a functional endpoint (UDDI requirement). Other tModels could be
describing things like security token service, etc. Therefore, description of
the manageability endpoint could also appear as yet another tModel in the
instance info list of a given UDDI binding. Manager merely investigates all
tModels in an instance info list looking for those that implement WSDM
manageability interfaces (WSDL 2.0) or manageability operations (checking
signatures in case of WSDL 1.1).
4. Manager could use
relationships: query at runtime or read from descriptive metadata. This is yet
to be discussed.
Possible ways to establish which
manageability endpoint manages which functional endpoint, given WSDL
descriptions of both endpoints.
A. The manager establishes
associations between functional and manageability endpoints by exercising
identification manageability capability on the manageability endpoint
(requests at runtime) and compares the returned reference to the given WSDL
information.
B. The manager establishes
associations between functional and manageability endpoint by comparing a
WSDM-specific tag on the wsdl:endpoint elements. For example <wsdl:endpoint
name="Functional" wsdm:target="urn:abc">, <wsdl:endpoint
name="Manageability" wsdm:target="urn:abc">
C. Manager could use descriptive
metadata e.g. relationships or otherwise. For example <wsdl:endpoint
name="Manageability" wsdm:target="urn:abc"> ... <wsdm:target uri="urn:abc"
service="s:MyService" endpoint="Functional">. Or similar metadata-based
approaches are possible.
-- Igor Sedukhin
.. ()
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