Traqula parser engine for SPARQL 1.1

Traqula Sparql 1.1 is a SPARQL 1.1 query parser for TypeScript.

Installation

npm install @traqula/parser-sparql-1-1

or

yarn add @traqula/parser-sparql-1-1

Import

Either through ESM import:

import {Parser} from 'engines/parser-sparql-1-1';

or CJS require:

const Parser = require('engines/parser-sparql-1-1').Parser;

Usage

This package contains a Parser that is able to parse SPARQL 1.1 queries:

const parser = new Parser();
const abstractSyntaxTree = parser.parse('SELECT * { ?s ?p ?o }');

Note that a single parser cannot parse multiple queries in parallel.

The package also contains multiple parserBuilders. These builders can be used either to consume to a parser, or to usage as a starting point for your own grammar.

Consuming parserBuilder to parser

At the core of Traqula, parser are constructed of multiple parser rules that have been consumed by the builder. This consumption returns a parser that can parse strings starting from any grammar rule.

The sparql11ParserBuilder for example contains both the rules queryOrUpdate and path (among many others). The consumption of sparql11ParserBuilder will thus return an object that has function queryOrUpdate and path. Calling those function with a string will cause that string to be parsed using the appropriate rule as a starting rule.

const parser: {
  queryOrUpdate: (input: string) => SparqlQuery;
  path: (input: string) => PropertyPath | IriTerm;
} = sparql11ParserBuilder.consumeToParser({
  tokenVocabulary: l.sparql11Tokens.build(),
}, {
  parseMode: new Set([ gram.canParseVars, gram.canCreateBlankNodes ]),
  dataFactory: new DataFactory(),
});

Constructing a new grammar from an existing one

The builders can also be used to construct new parsers. As an example the triplesBlockParserBuilder is created by merging the objectListBuilder with some new rules.

Configuration

Optionally, the following parameters can be set in the Parser constructor:

• dataFactory: A custom RDFJS DataFactory to construct terms and triples. (Default: require('@rdfjs/data-model'))
• baseIRI: An initial default base IRI. (Default: none)
• prefixes: An initial map of prefixes
• skipValidation: Can be used to disable the validation that used variables in a select clause are in scope.