W3C

PROV-DM Part 3: PROV-N: The Provenance Notation

Working Draft WD4 (internal release)

W3C Editor's Draft 09 March 2012

This version:
http://dvcs.w3.org/hg/prov/raw-file/default/model/releases/WD-prov-dm-20120309/prov-n.html
Latest published version:
http://www.w3.org/TR/prov-n/
Latest editor's draft:
http://dvcs.w3.org/hg/prov/raw-file/default/model/prov-n.html
Previous version:
none
Editors:
Luc Moreau, University of Southampton
Paolo Missier, Newcastle University
Author:
TBD

Abstract

PROV-DM is a data model for provenance that describes the entities, people and activities involved in producing a piece of data or thing in the world. PROV-DM is domain-agnostic, but is equipped with extensibility points allowing further domain-specific and application-specific extensions to be defined. PROV-DM is accompanied by PROV-N, a technology-independent notation, which allows serializations of PROV-DM instances to be created for human consumption, which facilitates the mapping of PROV-DM to concrete syntax, and which is used as the basis for a formal semantics of PROV-DM. The purpose of this document is to define the PROV-N notation.

Status of This Document

This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at http://www.w3.org/TR/.

This document is released internally by the Provenance Working Group.
This document is part of the PROV family of specifications, a set of specifications aiming to define the various aspects that are necessary to achieve the vision of inter-operable interchange of provenance information in heterogeneous environments such as the Web. This document defines the PROV-DM data model for provenance, accompanied with a notation to express instances of that data model for human consumption. Other documents are:

This document was published by the Provenance Working Group as an Editor's Draft. If you wish to make comments regarding this document, please send them to [email protected] (subscribe, archives). All feedback is welcome.

Publication as an Editor's Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by a group operating under the 5 February 2004 W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

Table of Contents

1. Introduction

Provenance is defined as a record that describes the people, institutions, entities, and activities, involved in producing, influencing, or delivering a piece of data or a thing in the world. Two companion specifications respectively define PROV-DM, a data model for provenance, allowing such descriptions to be expressed [PROV-DM] and a set of constraints that provenance descriptions are expectively to satisfy [PROV-DM-CONSTRAINTS].

In this context, PROV-N was introduced as a notation to write instances of the data model, as close to its abstract syntax as possible. PROV-N is primarily aimed at human consumption. PROV-N allows serializations of PROV-DM instances to be written in a technology independent manner. So far, PROV-N has been used in the following ways:

PROV-N was designed to be as close as possible to PROV-DM without the syntactic bias and modelling constraints that concrete technologies bring with them, e.g., XML's choice between attribute and element, RDF's reliance on triples, or JSON's usage of dictionaries.

The purpose of this document is solely to define the syntax of PROV-N. For each construct of PROV-DM, a corresponding PROV-N expression is introduced, by way of a production in the PROV-N grammar presented in this document.

This specification is one of several specifications, referred to as the PROV family of specifications, defining the various aspects that are necessary to achieve the vision of inter-operable exchange of provenance:

1.1 Structure of this Document

TODO

1.2 PROV-DM Namespace

The PROV-DM namespace is http://www.w3.org/ns/prov-dm/ (TBC).

All the elements, relations, reserved names and attributes introduced in this specification belong to the PROV-DM namespace.

There is a desire to use a single namespace that all specifications of the PROV family can share to refer to common provenance terms. This is ISSUE-224.

1.3 Conventions

The key words "must", "must not", "required", "shall", "shall not", "should", "should not", "recommended", "may", and "optional" in this document are to be interpreted as described in [RFC2119].

2. Grammar Notation

This specification includes a grammar for PROV-N expressed using the Extended Backus-Naur Form (EBNF) notation.

Each production rule (or production, for short) in the grammar defines one non-terminal symbol, in the form:

E ::= expression

Within the expression on the right-hand side of a rule, the following expressions are used to match strings of one or more characters:

3. PROV-DM Core

Instances of the PROV-DM data model are expressed in PROV-N by a text conformant with the toplevel production expression of the grammar. These expressions are grouped in two categories: elementExpression (see section Element) and relationExpression (see section Relation).

expression ::= elementExpression | relationExpression

elementExpression ::= entityExpression | activityExpression | agentExpression | noteExpression

relationExpression ::= generationExpression | usageExpression | derivationExpression | activityAssociationExpression | responsibilityExpression | startExpression | endExpression | alternateExpression | specializationExpression | annotationExpression

3.1 Element

PROV-DM elements can be entities, activities, agents, or notes. This section defines a production for the textual representation of each of these element types.

3.1.1 Entity

An entity's text matches the entityExpression production.

entityExpression ::= entity ( identifier optional-attribute-values )

optional-attribute-values ::= , [ attribute-values ]
attribute-values ::= attribute-value | attribute-value , attribute-values
attribute-value ::= attribute = Literal
entity(tr:WD-prov-dm-20111215)
entity(tr:WD-prov-dm-20111215, [ prov:type="document" ])
entity(tr:WD-prov-dm-20111215, [ prov:type="document", ex:version=2 ])

3.1.2 Activity

An activity's text matches the activityExpression production.

activityExpression ::= activity ( identifier , time , time optional-attribute-values )
activity(ex:edit1,,)
activity(ex:edit1,,,[prov:type="edit"])
activity(ex:a0, 2011-11-16T16:00:00,,[prov:type="createFile"])
activity(ex:a0, 2011-11-16T16:00:00, 2011-11-16T16:00:01, [prov:type="createFile"])

3.1.3 Agent

An agent's text matches the agentExpression production.

agentExpression ::= agent ( identifier optional-attribute-values )
agent(ag4)
agent(ag4, [ prov:type="prov:Human" %% xsd:QName, ex:name="David" ])

3.1.4 Note

A note's text matches the noteExpression production.

noteExpression ::= note ( identifier , attribute-values )
note(ann1,[ex:color="blue", ex:screenX=20, ex:screenY=30])

3.2 Relation

PROV-DM relations can be generation, usage, derivation, activity association, responsibility chain, activity start, activity end, alternate, specialization, or annotations. This section defines a production for the textual representation of each of these relation types.

3.2.1 Generation

A generation's text matches the generationExpression production.

generationExpression ::= wasGeneratedBy ( identifier , eIdentifier , aIdentifier , time optional-attribute-values )
wasGeneratedBy(tr:WD-prov-dm-20111215, ex:edit1)
wasGeneratedBy(tr:WD-prov-dm-20111215, ex:edit1, 2011-11-16T16:00:00)
wasGeneratedBy(ex:g1, tr:WD-prov-dm-20111215, ex:edit1)
wasGeneratedBy(e2, a1, [ex:fct="save"])     

3.2.2 Usage

A usage's text matches the usageExpression production.

usageExpression ::= used ( identifier , aIdentifier , eIdentifier , time optional-attribute-values )
used(ex:pub2, ar3:0111)
used(ex:pub2, ar3:0111, 2011-11-16T16:00:00)
used(ex:u1, ex:pub2, ar3:0111)
used(a1,e1,[ex:fct="load"])

3.2.3 Activity Association

An activity association's text matches the activityAssociationExpression productions of the grammar defined in this specification document.

activityAssociationExpression ::= wasAssociatedWith ( identifier, aIdentifier, agIdentifier ,eIdentifier optional-attribute-values )
wasAssociatedWith(ex:pub2, w3:Consortium)
wasAssociatedWith(ex:pub2, w3:Consortium  @ pr:rec-advance)
wasAssociatedWith(ex:pub2, w3:Consortium  @ pr:rec-advance, [prov:role="funder"])

3.2.4 Activity Start and End

Activity start and end texts match the startExpression and endExpression productions of the grammar defined in this specification document.

startExpression ::= wasStartedBy ( identifier, aIdentifier, agIdentifier optional-attribute-values )
endExpression ::= wasEndedBy ( identifier, aIdentifier, agIdentifier optional-attribute-values )

3.2.5 Responsibility Chain

responsibilityExpression ::= actedOnBehalfOf ( identifier, agIdentifier , agIdentifier , aIdentifier optional-attribute-values )
actedOnBehalfOf(ag1,ag2)
actedOnBehalfOf(ag1,ag2,a)
actedOnBehalfOf(ag1,ag2,[prov:type="delegation"])
actedOnBehalfOf(ag2,ag3,a,[prov:type="contract"])

3.2.6 Derivation

A derivation record's text matches the derivationExpression production.

derivationExpression ::= wasDerivedFrom ( identifier, eIdentifier , eIdentifier , aIdentifier , gIdentifier , uIdentifier optional-attribute-values )
wasDerivedFrom(tr:WD-prov-dm-20111215, tr:WD-prov-dm-20111018)
wasDerivedFrom(e2, e1, a, g2, u1)

3.2.7 Alternate and Specialization

An alternate relation's text matches the alternateExpression production.

alternateExpression ::= alternateOf ( eIdentifier , eIdentifier )
alternateOf(tr:WD-prov-dm-20111215,ex:alternate-20111215)

A specialization relation's text matches the specializationExpressionproduction.

specializationExpression ::= specializationOf ( eIdentifier , eIdentifier )
specializationOf(tr:WD-prov-dm-20111215,tr:prov-dm)

3.2.8 Annotation

A note's text matches the noteExpression production.

annotationExpression ::= hasAnnotation ( identifier , nIdentifier optional-attribute-values )
hasAnnotation(tr:WD-prov-dm-20111215,ex2:n1)

3.3 Further Expressions

This section defines further expressions of PROV-N.

3.3.1 Namespace Declaration

namespaceDeclarations ::= | defaultNamespaceDeclaration | namespaceDeclaration namespaceDeclaration
namespaceDeclaration ::= prefix prefix IRI
defaultNamespaceDeclaration ::= default IRI

In PROV-N, the prefix prov is reserved and denotes the PROV namespace.

3.3.2 Identifier

identifier ::= qualifiedName
eIdentifier ::= identifier (intended to denote an entity)
aIdentifier ::= identifier (intended to denote an activity)
agIdentifier ::= identifier (intended to denote an agent)
gIdentifier::= identifier (intended to denote a generation)
uIdentifier::= identifier (intended to denote a usage)
nIdentifier::= identifier (intended to denote a note)
accIdentifier::= identifier (intended to denote an account)

qualifiedName  ::= prefixedName | unprefixedName
prefixedName  ::= prefix : localPart
unprefixedName  ::= localPart
prefix  ::= a name without colon compatible with the NC_NAME production [XML-NAMES]
localPart  ::= a name without colon compatible with the NC_NAME production [XML-NAMES]
Note that XML NC_NAME don't allow local identifiers to start with a number. Instead, should we use the productions used in SPARQL or TURTLE?

3.3.3 Attribute

An attribute's text matches the attribute production.

attribute ::= qualifiedName

The reserved attributes in the PROV namespace are the following.

  1. prov:label
  2. prov:location
  3. prov:role
  4. prov:steps
  5. prov:type

3.3.4 Literal

A Literal's text matches the Literal production.

Literal  ::= typedLiteral | convenienceNotation
typedLiteral ::= quotedString %% datatype
datatype ::= qualifiedName
convenienceNotation  ::= stringLiteral | intLiteral
stringLiteral ::= quotedString
quotedString ::= a finite sequence of characters in which " (U+22) and \ (U+5C) occur only in pairs of the form \" (U+5C, U+22) and \\ (U+5C, U+5C), enclosed in a pair of " (U+22) characters
intLiteral ::= a finite-length sequence of decimal digits (#x30-#x39) with an optional leading negative sign (-)

The non terminals stringLiteral and intLiteral are syntactic sugar for quoted strings with datatype xsd:string and xsd:int, respectively.

In particular, a PROV-DM Literal may be an IRI-typed string (with datatype xsd:anyURI); such IRI has no specific interpretation in the context of PROV-DM.

3.3.4.1 Reserved Type Values

The reserved type values in the PROV namespace are the following.

  1. prov:AccountEntity
  2. prov:SoftwareAgent
  3. prov:Person
  4. prov:Organization
  5. prov:Plan
  6. prov:Collection
  7. prov:EmptyCollection
3.3.4.2 Time Values

Time instants are defined according to xsd:dateTime [XMLSCHEMA-2].

4. Common Relations

TO ADD

5. Expression Container

An expression container is a house-keeping construct of PROV-N capable of packaging up PROV-N expressions and namespace declarations. An expression container forms a self-contained package of provenance descriptions for the purpose of exchanging them. An expression container may be used to package up PROV-N expressions in response to a request for the provenance of something ([PROV-AQ]).

Given its status of house keeping construct for the purpose of exchanging provenance expressions, an expression container is not defined as a PROV-N expression (production expression).

An expression container, written container decls exprs endContainer in PROV-N, contains:

An expression container's text matches the expressionContainer production.

expressionContainer ::= container namespaceDeclarations expression endContainer

The following container contains expressions related to the provenance of entity e2.

container

  prefix ex: http://example.org/,

  entity(e2, [ prov:type="File", ex:path="/shared/crime.txt", ex:creator="Alice", 
             ex:content="There was a lot of crime in London last month."])
  activity(a1, 2011-11-16T16:05:00,,[prov:type="edit"])
  wasGeneratedBy(e2, a1, [ex:fct="save"])     
  wasAssociatedWith(a1, ag2, [prov:role="author"])
  agent(ag2, [ prov:type="prov:Person" %% xsd:QName, ex:name="Bob" ])

endContainer

This container could for instance be returned as the result of a query to a provenance store for the provenance of entity e2 [PROV-AQ].

Clarify what records are. This is ISSUE-208.

6. Account

PROV-DM has introduced a notion of account by which a set of provenance descriptions can be bundled up and named. PROV-DM assumes the existence of mechanisms to implement accounts, but such mechanisms remain outside its scope. It is suggested that specific serializations may offer solutions to name bundles of descriptions.

Given that the primary motivation for PROV-N is to provide a notation aimed at human consumption, it is therefore appropriate to introduce a notation for accounts, which would include an account name and a bundle of expressions.

An account, written account(id, exprs) in PROV-N, contains:

In PROV-N, an account's text matches the accountExpression production of the grammar.

accountExpression ::= account ( identifier , expression )

It is also useful to package up one or more account expressions in an expression container, for interchange purpose. Hence, expressionContainer is revised as follows.

expressionContainer ::= container namespaceDeclarations expression endContainer
| container namespaceDeclarations accountExpression endContainer

The following container

container
  prefix ex: http://example.org/,

  account(ex:acc1,...)
  account(ex:acc2,...)
endContainer

illustrates how two accounts with identifiers ex:acc1 and ex:acc2 can be returned in a PROV-N serialization of the provenance of something.

The following container

container
  prefix ex: http://example.org/,
  ...

  account(ex:acc1,
      entity(tr:WD-prov-dm-20111018, [ prov:type="pr:RecsWD" %% xsd:QName ])
      entity(tr:WD-prov-dm-20111215, [ prov:type="pr:RecsWD" %% xsd:QName ])
      ...
      wasAssociatedWith(ex:pub2, w3:Consortium  @ pr:rec-advance))

  account(ex:acc2,
      entity(ex:acc1, [prov:type="prov:AccountEntity" %% xsd:QName ])
      wasAttributedTo(ex1:acc1,w3:Consortium))

endContainer

illustrates a first account, with identifier ex:acc1, containing expressions describing the provenance of the technical report tr:WD-prov-dm-20111215, and a second account ex:acc2, describing the provenance of the first. In account ex:acc2, ex:acc1 is the identifier of an entity of type prov:AccountEntity.

A. References

A.1 Normative references

[OWL2-SYNTAX]
Boris Motik; Peter F. Patel-Schneider; Bijan Parsia. OWL 2 Web Ontology Language:Structural Specification and Functional-Style Syntax. 27 October 2009. W3C Recommendation. URL: http://www.w3.org/TR/2009/REC-owl2-syntax-20091027/
[PROV-O]
Satya Sahoo and Deborah McGuinness (eds.) Khalid Belhajjame, James Cheney, Daniel Garijo, Timothy Lebo, Stian Soiland-Reyes, and Stephan Zednik Provenance Formal Model. 2011, Working Draft. URL: http://www.w3.org/TR/prov-o/
[RFC2119]
S. Bradner. Key words for use in RFCs to Indicate Requirement Levels. March 1997. Internet RFC 2119. URL: http://www.ietf.org/rfc/rfc2119.txt
[XML-NAMES]
Richard Tobin; et al. Namespaces in XML 1.0 (Third Edition). 8 December 2009. W3C Recommendation. URL: http://www.w3.org/TR/2009/REC-xml-names-20091208/
[XMLSCHEMA-2]
Paul V. Biron; Ashok Malhotra. XML Schema Part 2: Datatypes Second Edition. 28 October 2004. W3C Recommendation. URL: http://www.w3.org/TR/2004/REC-xmlschema-2-20041028/

A.2 Informative references

[PROV-AQ]
Graham Klyne and Paul Groth (eds.) Luc Moreau, Olaf Hartig, Yogesh Simmhan, James Meyers, Timothy Lebo, Khalid Belhajjame, and Simon Miles Provenance Access and Query. 2011, Working Draft. URL: http://www.w3.org/TR/prov-aq/
[PROV-DM]
Luc Moreau and Paolo Missier (eds.) ... PART 1: PROV-DM .... 2011, Working Draft. URL: http://www.w3.org/TR/prov-dm/
[PROV-DM-CONSTRAINTS]
Luc Moreau and Paolo Missier (eds.) ... PROV-DM Constraints. 2011, Working Draft. URL: http://www.w3.org/TR/prov-dm-constraints/
[PROV-PRIMER]
Yolanda Gil and Simon Miles (eds.) Khalid Belhajjame, Helena Deus, Daniel Garijo, Graham Klyne, Paolo Missier, Stian Soiland-Reyes, and Stephan Zednik Prov Model Primer. 2011, Working Draft. URL: http://www.w3.org/TR/prov-primer/
[PROV-RDF]
James CheneyPROV-RDF Mapping 2012, Working in Progress. URL: http://www.w3.org/2011/prov/wiki/ProvRDF
[PROV-SEM]
James Cheney Formal Semantics Strawman. 2011, Work in progress. URL: http://www.w3.org/2011/prov/wiki/FormalSemanticsStrawman
[PROV-XML]
James CheneyPROV-XML Mapping 2012, Working in Progress. URL: http://www.w3.org/2011/prov/wiki/ProvXML