Skip to main content

Notice: this Wiki will be going read only early in 2024 and edits will no longer be possible. Please see: https://gitlab.eclipse.org/eclipsefdn/helpdesk/-/wikis/Wiki-shutdown-plan for the plan.

Jump to: navigation, search

COSMOS Design 208584

Revision as of 17:31, 4 December 2007 by David whiteman.us.ibm.com (Talk | contribs) ('''Spec changes summary table''')

Update CMDBf query and registration service implementations to 1.0 spec level

This is the design document for bugzilla 208584. This documents the approach we are taking to update the query and registration service implementations from the CMDBf 0.95 spec to CMDBf 1.0.

Change History

Name: Date: Revised Sections:
David Whiteman 11/21/2007
  • Initial version

Workload Estimation

Rough workload estimate in person weeks
Process Sizing Names of people doing the work
Design 1 David
Code 1 David
Test 0.4 David
Documentation 0.2
Build and infrastructure 0.2
Code review, etc.* 0.2
TOTAL 3.0

Terminologies/Acronyms

The terminologies/acronyms below can be used throughout this document. The list below defines each term regarding how it is used in this document:

Term Definition
MDR Management Data Repository
CMDBf Specification for a CMDB that federates between multiple MDRs
CMDB Configuration Management Database
SML Service Modeling Language - An XML-based language used for modeling
SML Model A set of SML compliant resources
SML Repository The SML Repository describes any SML model together with a set of COSMOS API used to add new SML resources to the SML model and to query the SML model.
CMDBf query MDRs make data available via a query service defined in the CMDBf specification. The input and output of a CMDBf query is a structured XML document described in the specification.
CMDBf toolkit The name given to the CMDBf query and registration service framework and MDR utilities as provided by COSMOS

Purpose

This enhancement is associated with bugzilla 208584.

The purpose of this enhancement is to describe the approach we are taking to update the query and registration service implementations from the CMDBf 0.95 spec to CMDBf 1.0.

Spec Change Impacts

The following spec changes impact the implementation of the CMDBf toolkit in COSMOS. Here are the major highlights:

  • CMDBf 1.0 introduces the concept of a recordMetadata element to the query response that contains "common information about the record itself". There is also a new recordMetadata attribute on the propertyValue element that "indicates the property to be evaluated is in the <recordMetadata> element of the record".
  • recordTypeSelector and propertyValueSelector are renamed and aggregated under a common parent element, recordConstraint. The details are in the spec changes summary table.
  • xpath1Selector is renamed xpathExpression, and is now mutually exclusive of all other subelements commonly shared between itemTemplate and relationshipTemplate elements. Further, a dialect attribute has been added so that XPath content is not restricted to the 1.0 version of XPath. The subelement formerly named xpathExpression that contains the raw XPath content is now named expression.
  • depthLimit is a new subelement of relationshipTemplate that defines whether multiple edges or nodes should be traversed when conducting the query
  • propertySubsetDirective is now contentSelector and has a matchedRecords attribute that controls whether returned record content must match the selected type. Also, the selectedRecordType element has been introduced to control whether entire records or selected properties (through use of selectedProperty child elements) are returned.
  • the mdrId element of the <registerRequest> element has been corrected to be defined as anyURI instead of MdrScopedType in the schema
  • The specification now indicates a set of graph query faults and register operation faults that should be issued in certain failure conditions are met when processing a query, registration, or deregistration request. These are enumerated in sections 4.3.3, 5.2.3, and 5.2.6 of the spec. The query and registration services will need to define and throw special exception types containing the code, subcode, reason, and detail data. The MDR code will need to handle these exceptions and envelop them in a SOAP fault as part of the web service failure.
  • Section 6 of the 1.0 spec describes new constructs called queryServiceMetadata and registrationServiceMetadata. These are provided so that a federating CMDB can determine which capabilities and data models are supported by a given MDR.
NOTE TO REVIEWERS: This is a new addition to the CMDBf schema that is optional to be implemented, but seems to be a key future component to the reconciliation taxonomy.  Does this implementation need to be done near term, and does it belong in the cmdbf.query modules, or in the MDR toolkit code?

Spec changes summary table

Here is a summary in table form of some of the direct high-level changes in the CMDBf spec for version 1.0.

CMDBf 0.95 keyword CMDBf 1.0 keyword
N/A recordMetadata
N/A recordConstraint
recordTypeSelector recordType
propertyValueSelector propertyValue
instanceIdSelector instanceIdConstraint
xpath1Selector xpathExpression
xpathExpression expression
propertySubsetDirective contentSelector
dropDirective suppressFromResult
source sourceTemplate
target targetTemplate
N/A depthLimit
sourceItem source
targetItem target

Task Breakdown

The following section includes the tasks required to complete this enhancement.

208584-pert.jpg

  1. Copy the new data model schema to the COSMOS code base
  2. Update the XML in the JUnit testcases to reflect the changed data model
  3. Update the interfaces representing data model artifacts
  4. Update the concrete implementations of those interfaces found in the cmdbf.query plug-in to match the new API changes
  5. Update SAX parser code that transforms XML to artifacts
  6. Update the toXML() methods that convert artifacts to XML representation
  7. Update the code snippets in the JUnit testcases that make use of factory classes to instantiate artifacts for testing
  8. Update the rest of the common query and registration service code
  9. Update the SML repository code that uses the query service
  10. Update the example query & registration service code
  11. Notify early adopters (e.g. the CMDBf toolkit, also found in the data collection subproject) of previous implementation of changed COSMOS code, so they can change their implementations

Open Issues/Questions

All reviewer feedback should go in the Talk page for 208584.


Back to the top