1 Introduction

• this version only describes WSML-Standard, as complement to WSMO-Standard. A version for WSML-Lite and WSML-Full will have to be defined also.
• this version does not describe the concepts of choreography and orchestration, as they are not defined in WSMO-Standard yet. A grounding of a Web Service to a URI is therefore not described yet, as this will be part of the choreography.
• this version does not prescribe a syntax for logical expressions; in the grammar, a logical expression is represented by an arbitrary string. This is done for two reasons: first, the grammar becomes language-independent, it is up to a reasoner to decide whether the logical expression encoded in the string is valid. This allows using different logical languages (with different reasoners) while using WSML. The second reason is pragmatic: since the language evolves continuously, and decisions on the logical syntax change rapidly, we postpone defining the syntax for the logical expressions until some stable developments are reached.

2 Example

3 BNF grammar for WSML

header {
package deri.wsmo.bnf.validator;
}

class WSMLParser extends Parser;

wsmoDefinition:
	(ontologyDefinition | webServiceDefinition | goalDefinition | mediatorDefinition)*	
;

nameSpaceDefinition:
	NAMESPACE (uri)?
	(COMMA nameSpaceBlock)*
	(TARGETNAMESPACE uri)?
;

nameSpaceBlock:
	uri EQUAL uri;
	
goalDefinition:
	GOAL uri
		(nameSpaceDefinition)?
		(nonFunctionalDefinition)?
		(USEMEDIATOR uri (COMMA uri)*)?
		((POSTCONDITION | EFFECT) axiomDefinition)+
	;

mediatorDefinition:
	ooMediatorDefinition | ggMediatorDefinition | wgMediatorDefinition | wwMediatorDefinition
	;
	
ooMediatorDefinition:
	OOMEDIATOR uri
		(nameSpaceDefinition)?
		(nonFunctionalDefinition)?
		(SOURCE uri)+ // ontology or ooMediator 
		(TARGET uri)+ // ontology or goal or webservice or mediator
		(USESERVICE uri)? // goal or wwMediator
;

ggMediatorDefinition:
	GGMEDIATOR uri
		(nameSpaceDefinition)?
		(nonFunctionalDefinition)?
		SOURCE uri // goal or ggMediator
		TARGET uri // goal or ggMediator
		(USEMEDIATOR uri (COMMA uri)*)? //ooMediator
		(REDUCTION axiomDefinition)?
;

wgMediatorDefinition:
	WGMEDIATOR uri
		(nameSpaceDefinition)?
		(nonFunctionalDefinition)?
		SOURCE uri // webservice or wgMediator
		TARGET uri // goal or wgMediator
		(USEMEDIATOR uri (COMMA uri)*)?// ooMediator
		(REDUCTION axiomDefinition)?
;

wwMediatorDefinition:
	WWMEDIATOR uri
		(nameSpaceDefinition)?
		(nonFunctionalDefinition)?
		SOURCE uri // webservice or wwMediator
		TARGET uri // webservice or wwMediator
		(USEMEDIATOR uri (COMMA uri)*)? // ooMediator
;

webServiceDefinition:
	WEBSERVICE uri
		(nameSpaceDefinition)?
		(nonFunctionalWSDefinition)?
		(USEMEDIATOR uri (COMMA uri)*)?
		(capabilityDefinition)?
		(interfaceDefinition)*
	;
	
nonFunctionalWSDefinition:
	NFP
		nonFunctionalProperties
		(PERFORMANCE (String | uri))?
		(RELIABILITY (String | uri))?
		(SECURITY (String | uri))?
		(SCALABILITY (String | uri))?
		(ROBUSTNESS (String | uri))?
		(ACCURACY (String | uri))?
		(TRANSACTIONAL (String | uri))?
		(TRUST (String | uri))?
		(FINANCIAL (String | uri))?
		(NETWORKQOS (String | uri))?
	;
	
capabilityDefinition:
	(USECAPABILITY uri) |
	(CAPABILITY uri
		(nonFunctionalDefinition)?
		(USEMEDIATOR uri (COMMA uri)*)?
		( (PRECONDITION | POSTCONDITION | ASSUMPTION | EFFECT) axiomDefinition)+
	)
	;

interfaceDefinition:
	(USEINTERFACE uri) |
	(INTERFACE uri
		(nonFunctionalDefinition)?
		(USEMEDIATOR uri (COMMA uri)*)?
		choreographyDefinition
		(orchestrationDefinition)?
	)
	;
	
choreographyDefinition:
	CHOREOGRAPHY PLACEHOLDER
;

orchestrationDefinition:
	ORCHESTRATION PLACEHOLDER
;
	
	
ontologyDefinition:
	ONTOLOGY uri
		(nameSpaceDefinition)?
		(nonFunctionalDefinition)?
		(USEMEDIATOR uri (COMMA uri)*)?
		(conceptDefinition | axiomDefinition | instanceDefinition | relationDefinition | 
                variableDefinition | functionDefinition)*
	;

conceptDefinition:
	CONCEPT uri 
		(nonFunctionalDefinition)?
		(SUBCONCEPT uri )? 
		(attributeDefinition)*
		(methodDefinition)*
	;
	
methodDefinition:
	METHOD 
		(nonFunctionalDefinition)?
		(parameterDefinition)*
		(rangeDefinition)?
	;

rangeDefinition:
	RANGE uri OFTYPE uri
	;

variableDefinition:
	VARIABLE uri (COMMA uri)* MEMBEROF uri
	;

functionDefinition:
	FUNCTION uri
		(nonFunctionalDefinition)?
		(parameterDefinition)*
		(rangeDefinition)?
	;

attributeDefinition:
	uri OFTYPE (SET)? uri
	;

instanceDefinition:
	INSTANCE uri MEMBEROF uri
		(uri valueDefinition )*
	;

valueDefinition:
	(HASVALUE value) | 
	(HASVALUES CURLYLEFT value (COMMA value)* CURLYRIGHT)
	;

value: String | uri;

relationDefinition: 
	RELATION uri
		(nonFunctionalDefinition)?
		parameterDefinition
	;

parameterDefinition:
	PARAMETER uri OFTYPE uri
	;
	
axiomDefinition:
	AXIOM uri
		(nonFunctionalDefinition)?
		logicalExpression
	;
	
logicalExpression:
	BEGINLOGIC
	  String 
	ENDLOGIC
;

nonFunctionalDefinition:
	NFP nonFunctionalProperties
	;

nonFunctionalProperties:
	(TITLE (uri | a:String))?
	(CREATOR (oneOreMoreuriOrString))?
	(SUBJECT (oneOreMoreuriOrString))?
	(DESCRIPTION (oneOreMoreuriOrString))?
	(PUBLISHER (oneOreMoreuriOrString))?
	(CONTRIBUTOR (oneOreMoreuriOrString))?
	(DATE (uri | String))?
	(TYPE (oneOreMoreuriOrString))?
	(FORMAT (oneOreMoreuriOrString))?
	(DCSOURCE (oneOreMoreuriOrString))?
	(LANGUAGE (oneOreMoreuriOrString))?
	(DCRELATION (oneOreMoreuriOrString))?
	(COVERAGE (oneOreMoreuriOrString))?
	(RIGHTS (oneOreMoreuriOrString))?
	(VERSION (uri | String))?	
;

oneOreMoreuriOrString: (uri | String) (COMMA (uri | String))* 	;
uri: (NCName ":")=> NCName ":" NCName | NCName;


class WSMLLexer extends Lexer;
options {
	k=10;
	charVocabulary = '\u0003'..'\uFFFF';
	testLiterals = false;
}

protected NCBegin : (LowerCaseLetter | Underscore | UpperCaseLetter);
protected NCRest: (NCBegin | POINT | Dash | Hash | Slash | Amp | Question | Digit | Colon | Tilde);

NCName options { testLiterals = true ;}	: 
	 NCBegin (NCRest)*;

// white and other skippers
WS: (' ' | '\n' |'\t'| '\r' {newline();})+ {$setType(Token.SKIP);} ;
SLComment : "comment:" (~('\n'|'\r'))* ('\n'|'\r') {newline();} {$setType(Token.SKIP);} ;


// internal lexer tokens
protected Dash: '-';
protected Hash: '#';
protected Slash: '/';
protected Amp: '&';
protected Question: '?';
protected Underscore: '_';
protected Colon : ':';
protected LowerCaseLetter: 'a'..'z';
protected UpperCaseLetter: 'A'..'Z';
protected Digit: '0'..'9';
protected Tilde: '~';
//protected URICharacter: (LowerCaseLetter | UpperCaseLetter | Digit | StrangeCharacter | Colon );

// single characters
COMMA: ',';
EQUAL: '=';
protected POINT: '.';

String: '"' (~'"')* '"' ;
NAMESPACE : "namespace";
TARGETNAMESPACE: "target-namespace";

USEMEDIATOR : "use-mediator";
OOMEDIATOR : "oo-mediator";
GGMEDIATOR : "gg-mediator";
WGMEDIATOR : "wg-mediator";
WWMEDIATOR : "ww-mediator";
SOURCE : "source";
TARGET : "target";
USESERVICE : "use-service";
REDUCTION : "reduction";

GOAL : "goal";
WEBSERVICE : "webservice";

USECAPABILITY: "use-capability";
CAPABILITY: "capability";
PRECONDITION: "precondition";
POSTCONDITION: "postcondition";
ASSUMPTION: "assumption";
EFFECT: "effect";

USEINTERFACE: "use-interface";
INTERFACE: "interface";

CHOREOGRAPHY: "choreography";
ORCHESTRATION: "orchestration";
PLACEHOLDER: "***";

ONTOLOGY: "ontology";
CONCEPT: "concept";
SUBCONCEPT: "subconceptOf";
OFTYPE: "oftype";
SET: "set";
INSTANCE: "instance";
MEMBEROF: "memberOf";
HASVALUE: "hasvalue";
HASVALUES: "hasvalues";

RELATION: "relation";
PARAMETER: "parameter";
FUNCTION: "function";
VARIABLE: "variable";
METHOD: "method";
RANGE: "range";

AXIOM: "axiom";
BEGINLOGIC: "logical-expression";
ENDLOGIC: "end-logical-expression";

TITLE: "dc:title";
CREATOR: "dc:creator";
SUBJECT: "dc:subject";
DESCRIPTION: "dc:description";
PUBLISHER: "dc:publisher";
CONTRIBUTOR: "dc:contributor";
DATE: "dc:date";
TYPE: "dc:type";
FORMAT: "dc:format";
DCSOURCE: "dc:source";
LANGUAGE: "dc:language";
DCRELATION: "dc:relation";
COVERAGE: "dc:coverage";
RIGHTS: "dc:rights";
VERSION: "version";

NFP : "non-functional-properties";
PERFORMANCE : "performance";
RELIABILITY : "reliability";
SECURITY : "security";
SCALABILITY : "scalability";
ROBUSTNESS : "robustness";
ACCURACY : "accuracy";
TRANSACTIONAL : "transactional";
TRUST : "trust";
FINANCIAL : "financial";
NETWORKQOS : "network-related-qos";

4 Acknowledgment

The work is funded by the European Commission under the projects DIP, Knowledge Web, Ontoweb, SEKT, SWWS, Esperonto and h-TechSight; by Science Foundation Ireland under the DERI-Lion project; and by the Vienna city government under the CoOperate program.

The editors would like to thank all the members of the WSMO working group for their advice and input into this document.