The Mellon-Funded Fedora Project Technical Specifications Review August 26, 2002

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The Mellon-Funded Fedora ProjectTechnical
Specifications ReviewAugust 26, 2002

• Sandy Payette
• Cornell Information Science

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The New FEDORA

• Technical Specifications Part II

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Fedora Access Sub-System
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FEDORA Implementation Technologies

• Fedora Web Services Layer
• Apache Axis for SOAP over HTTP
• Apache Tomcat 4.1
• Core Repository System
• Sun JDK1.4
• Xerces 2.0.2 for XML parsing
• Deployment Platforms
• Windows
• Solaris
• Linux

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Fedora Management Sub-System API-M

• Object Management
• Object Component Management
• Object Validation
• PID Generation
• Interacts with Storage Subsystem

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Object Management Operations(in API-M)

• Ingest Object
• Get Object XML
• Export Object
• Withdraw Object
• Delete Object
• Purge Object
• Obtain Lock on Object
• Release Lock

• Get Object State
• Get Object Audit Trail

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Object State
State Definition
A Active
L Locked
R Replicating
N Incomplete
W Withdrawn
C Marked for Deletion
D Pending Deletion
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Component Management Operations(in API-M)

• Add (Datastream or Disseminator)
• Modify (Datastream or Disseminator)
• Withdraw (Datastream or Disseminator)
• Delete (Datastream or Disseminator)
• Purge (Datastream or Disseminator)
• Get (Datastream or Disseminator)
• Get History (Datastream or Disseminator)

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Component State
State Definition
A Active
W Withdrawn
C Marked for Deletion
D Pending Deletion
B Broken Link
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Object Validation

• Runs before an XML object is accepted into the
  repository for storage
• During ingest of XML object created outside of
  repository
• Before final commit of object built up via API-M
• XML Schema Validation (to METS Schema)
• Fedora Rules Validation (via Schematron)
• Referential integrity
• Required values for attributes
• Allowable state transitions (object state and
  component state)

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Fedora Storage Sub-System
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Storage Sub-system Object Reader and Writer
Modules
DOWriter
DOReader
DisseminatingDOReader
DefinitiveDOReader
DefinitiveDOWriter
FastDOReader
DataStore
External Content Retriever
Behavior Service Resolver
DataStore-FS
Dissemination Cache DB
Managed Content Datastreams
XML Objects
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Digital Object XML The Inner View

• PID
• System Metadata Object Audit Trail
• Datastreams 3 kinds
• Disseminators pointing to behavior objects

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PID Syntax

• Conforms to URN Syntax (RFC2141)
• Syntax
• Namespace prefix (hyphen separators)
• Delimiter ()
• Object identifier string (sequential number)
• Examples
• uva-lib1225
• cornell-cs101
• uva-bdef10
• uva-bmech12

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System Metadata Object Audit Trail

• Audit trail record put in object for all API-M
  transactions
• Fedora XML Schema for Audit trail metadata

ltfedoraAuditrecordgt ltfedoraAuditprocess
type/gt ltfedoraAuditactiongt
lt/fedoraAuditactiongt ltfedoraAuditresponsibility
gt lt/fedoraAuditresponsibilitygt ltfedoraAuditdate
gt lt/fedoraAuditdategt ltfedoraAuditjustificationgt
lt/fedoraAuditjustificationgt lt/fedoraAuditrecord
gt
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Datastreams 3 Kinds

• Referenced External Content
• Outside custodianship of repository
• Referenced in digital object XML via a URI
• Repository Managed Content
• Under custodianship of repository
• Referenced in digital object XML via internal
  datastream identifier
• Implementer-defined XML Metadata
• Bound to the digital object
• Stored in-line as part of digital object XML

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Digital Object XML StorageSample Object
Click here for test digital object
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Digital Object XML Storage Sample Behavior
Definition Object
Click here for Behavior Definition object for
Image-W
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Digital Object XML Storage Sample Behavior
Mechanism Object
Click here for Behavior Mechanism object for
UVA_Image_-W
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(No Transcript)
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Questions and Discussion
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FEDORA Web Site http//www.fedora.info