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rdflib

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an RDF library for node.js. Suitable for client and server side.

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"use strict"; var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault"); Object.defineProperty(exports, "__esModule", { value: true }); exports.default = void 0; var _defineProperty2 = _interopRequireDefault(require("@babel/runtime/helpers/defineProperty")); var _classOrder = _interopRequireDefault(require("./class-order")); var _collection = _interopRequireDefault(require("./collection")); var _canonicalDataFactory = _interopRequireDefault(require("./factories/canonical-data-factory")); var _log = _interopRequireDefault(require("./log")); var _namespace = _interopRequireDefault(require("./namespace")); var _nodeInternal = _interopRequireDefault(require("./node-internal")); var _serialize = _interopRequireDefault(require("./serialize")); var _types = require("./types"); var _terms = require("./utils/terms"); var _variable = _interopRequireDefault(require("./variable")); var _utils = require("./utils"); var _namedNode = _interopRequireDefault(require("./named-node")); /** * A formula, or store of RDF statements */ class Formula extends _nodeInternal.default { /** * Initializes this formula * @constructor * @param statements - Initial array of statements * @param constraints - initial array of constraints * @param initBindings - initial bindings used in Query * @param optional - optional * @param opts * @param opts.rdfFactory - The rdf factory that should be used by the store */ constructor() { var _this; let statements = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : []; let constraints = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : []; let initBindings = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : []; let optional = arguments.length > 3 && arguments[3] !== undefined ? arguments[3] : []; let opts = arguments.length > 4 && arguments[4] !== undefined ? arguments[4] : {}; super(''); _this = this; this.statements = statements; this.constraints = constraints; this.initBindings = initBindings; this.optional = optional; (0, _defineProperty2.default)(this, "termType", _types.GraphTermType); (0, _defineProperty2.default)(this, "classOrder", _classOrder.default.Graph); /** * The accompanying fetcher instance. * * Is set by the fetcher when initialized. */ (0, _defineProperty2.default)(this, "fetcher", void 0); (0, _defineProperty2.default)(this, "isVar", 0); /** * A namespace for the specified namespace's URI * @param nsuri The URI for the namespace */ (0, _defineProperty2.default)(this, "ns", _namespace.default); /** The factory used to generate statements and terms */ (0, _defineProperty2.default)(this, "rdfFactory", void 0); this.rdfFactory = opts && opts.rdfFactory || _canonicalDataFactory.default; // Enable default factory methods on this while preserving factory context. for (const factoryMethod of _utils.appliedFactoryMethods) { this[factoryMethod] = function () { return _this.rdfFactory[factoryMethod](...arguments); }; } } /** Add a statement from its parts * @param subject - the first part of the statement * @param predicate - the second part of the statement * @param object - the third part of the statement * @param graph - the last part of the statement */ add(subject, predicate, object, graph) { if (arguments.length === 1) { subject.forEach(st => this.add(st.subject, st.predicate, st.object, st.graph)); } return this.statements.push(this.rdfFactory.quad(subject, predicate, object, graph)); } /** Add a statment object * @param {Statement} statement - An existing constructed statement to add */ addStatement(statement) { return this.add(statement); } /** * Shortcut for adding blankNodes * @param [id] */ bnode(id) { return this.rdfFactory.blankNode(id); } /** * Adds all the statements to this formula * @param statements - A collection of statements */ addAll(statements) { statements.forEach(quad => { this.add(quad.subject, quad.predicate, quad.object, quad.graph); }); } /** Follow link from one node, using one wildcard, looking for one * * For example, any(me, knows, null, profile) - a person I know accoring to my profile . * any(me, knows, null, null) - a person I know accoring to anything in store . * any(null, knows, me, null) - a person who know me accoring to anything in store . * * @param s - A node to search for as subject, or if null, a wildcard * @param p - A node to search for as predicate, or if null, a wildcard * @param o - A node to search for as object, or if null, a wildcard * @param g - A node to search for as graph, or if null, a wildcard * @returns A node which match the wildcard position, or null */ any(s, p, o, g) { const st = this.anyStatementMatching(s, p, o, g); if (st == null) { return null; } else if (s == null) { return st.subject; } else if (p == null) { return st.predicate; } else if (o == null) { return st.object; } return null; } /** * Gets the value of a node that matches the specified pattern * @param s The subject * @param p The predicate * @param o The object * @param g The graph that contains the statement */ anyValue(s, p, o, g) { const y = this.any(s, p, o, g); return y ? y.value : void 0; } /** * Gets the first JavaScript object equivalent to a node based on the specified pattern * @param s The subject * @param p The predicate * @param o The object * @param g The graph that contains the statement */ anyJS(s, p, o, g) { const y = this.any(s, p, o, g); return y ? _nodeInternal.default.toJS(y) : void 0; } /** * Gets the first statement that matches the specified pattern */ anyStatementMatching(s, p, o, g) { let x = this.statementsMatching(s, p, o, g, true); if (!x || x.length === 0) { return undefined; } return x[0]; } /** * Returns a unique index-safe identifier for the given term. * * Falls back to the rdflib hashString implementation if the given factory doesn't support id. */ id(term) { return this.rdfFactory.id(term); } /** * Search the Store * This is really a teaching method as to do this properly you would use IndexedFormula * * @param s - A node to search for as subject, or if null, a wildcard * @param p - A node to search for as predicate, or if null, a wildcard * @param o - A node to search for as object, or if null, a wildcard * @param g - A node to search for as graph, or if null, a wildcard * @param justOne - flag - stop when found one rather than get all of them? * @returns {Array<Node>} - An array of nodes which match the wildcard position */ statementsMatching(s, p, o, g, justOne) { const sts = this.statements.filter(st => (!s || s.equals(st.subject)) && (!p || p.equals(st.predicate)) && (!o || o.equals(st.object)) && (!g || g.equals(st.graph))); if (justOne) { return sts.length === 0 ? [] : [sts[0]]; } return sts; } /** * Finds the types in the list which have no *stored* subtypes * These are a set of classes which provide by themselves complete * information -- the other classes are redundant for those who * know the class DAG. * @param types A map of the types */ bottomTypeURIs(types) { let bots; let bottom; let elt; let i; let len; let ref; let subs; let v; bots = []; for (let k in types) { if (!types.hasOwnProperty(k)) continue; v = types[k]; subs = this.each(void 0, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#subClassOf'), this.rdfFactory.namedNode(k)); bottom = true; i = 0; for (len = subs.length; i < len; i++) { elt = subs[i]; ref = elt.uri; if (ref in types) { // the subclass is one we know bottom = false; break; } } if (bottom) { bots[k] = v; } } return bots; } /** Creates a new collection */ collection() { return new _collection.default(); } /** Follow links from one node, using one wildcard. * * For example, each(me, knows, null, profile) - people I know accoring to my profile . * each(me, knows, null, null) - people I know accoring to anything in store . * each(null, knows, me, null) - people who know me accoring to anything in store . * * @param s - A node to search for as subject, or if null, a wildcard * @param p - A node to search for as predicate, or if null, a wildcard * @param o - A node to search for as object, or if null, a wildcard * @param g - A node to search for as graph, or if null, a wildcard * @returns {Array<Node>} - An array of nodes which match the wildcard position */ each(s, p, o, g) { const results = []; let sts = this.statementsMatching(s, p, o, g, false); if (s == null) { for (let i = 0, len = sts.length; i < len; i++) { results.push(sts[i].subject); } } else if (p == null) { for (let l = 0, len1 = sts.length; l < len1; l++) { results.push(sts[l].predicate); } } else if (o == null) { for (let m = 0, len2 = sts.length; m < len2; m++) { results.push(sts[m].object); } } else if (g == null) { for (let q = 0, len3 = sts.length; q < len3; q++) { results.push(new _namedNode.default(sts[q].graph.value)); } } return results; } /** * Test whether this formula is equals to {other} * @param other - The other formula */ equals(other) { if (!other) { return false; } return this.hashString() === other.hashString(); } /** * For thisClass or any subclass, anything which has it is its type * or is the object of something which has the type as its range, or subject * of something which has the type as its domain * We don't bother doing subproperty (yet?)as it doesn't seeem to be used * much. * Get all the Classes of which we can RDFS-infer the subject is a member * @return a hash of URIs */ findMembersNT(thisClass) { let len2; let len4; let m; let members; let pred; let ref; let ref1; let ref2; let ref3; let ref4; let ref5; let seeds; let st; let u; seeds = {}; seeds[thisClass.toNT()] = true; members = {}; ref = this.transitiveClosure(seeds, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#subClassOf'), true); for (let t in ref) { if (!ref.hasOwnProperty(t)) continue; ref1 = this.statementsMatching(void 0, this.rdfFactory.namedNode('http://www.w3.org/1999/02/22-rdf-syntax-ns#type'), this.fromNT(t)); for (let i = 0, len = ref1.length; i < len; i++) { st = ref1[i]; members[st.subject.toNT()] = st; } ref2 = this.each(void 0, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#domain'), this.fromNT(t)); for (let l = 0, len1 = ref2.length; l < len1; l++) { pred = ref2[l]; ref3 = this.statementsMatching(void 0, pred); for (m = 0, len2 = ref3.length; m < len2; m++) { st = ref3[m]; members[st.subject.toNT()] = st; } } ref4 = this.each(void 0, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#range'), this.fromNT(t)); for (let q = 0, len3 = ref4.length; q < len3; q++) { pred = ref4[q]; ref5 = this.statementsMatching(void 0, pred); for (u = 0, len4 = ref5.length; u < len4; u++) { st = ref5[u]; members[st.object.toNT()] = st; } } } return members; } /** * For thisClass or any subclass, anything which has it is its type * or is the object of something which has the type as its range, or subject * of something which has the type as its domain * We don't bother doing subproperty (yet?)as it doesn't seeem to be used * much. * Get all the Classes of which we can RDFS-infer the subject is a member * @param subject - A named node */ findMemberURIs(subject) { return this.NTtoURI(this.findMembersNT(subject)); } /** * Get all the Classes of which we can RDFS-infer the subject is a superclass * Returns a hash table where key is NT of type and value is statement why we * think so. * Does NOT return terms, returns URI strings. * We use NT representations in this version because they handle blank nodes. */ findSubClassesNT(subject) { let types = {}; types[subject.toNT()] = true; return this.transitiveClosure(types, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#subClassOf'), true); } /** * Get all the Classes of which we can RDFS-infer the subject is a subclass * @param {RDFlibNamedNode} subject - The thing whose classes are to be found * @returns a hash table where key is NT of type and value is statement why we * think so. * Does NOT return terms, returns URI strings. * We use NT representations in this version because they handle blank nodes. */ findSuperClassesNT(subject) { let types = {}; types[subject.toNT()] = true; return this.transitiveClosure(types, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#subClassOf'), false); } /** * Get all the Classes of which we can RDFS-infer the subject is a member * todo: This will loop is there is a class subclass loop (Sublass loops are * not illegal) * @param {RDFlibNamedNode} subject - The thing whose classes are to be found * @returns a hash table where key is NT of type and value is statement why we think so. * Does NOT return terms, returns URI strings. * We use NT representations in this version because they handle blank nodes. */ findTypesNT(subject) { let domain; let range; let rdftype; let ref; let ref1; let ref2; let ref3; let st; let types; rdftype = 'http://www.w3.org/1999/02/22-rdf-syntax-ns#type'; types = []; ref = this.statementsMatching(subject, void 0, void 0); for (let i = 0, len = ref.length; i < len; i++) { st = ref[i]; if (st.predicate.uri === rdftype) { types[st.object.toNT()] = st; } else { ref1 = this.each(st.predicate, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#domain')); for (let l = 0, len1 = ref1.length; l < len1; l++) { range = ref1[l]; types[range.toNT()] = st; } } } ref2 = this.statementsMatching(void 0, void 0, subject); for (let m = 0, len2 = ref2.length; m < len2; m++) { st = ref2[m]; ref3 = this.each(st.predicate, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#range')); for (let q = 0, len3 = ref3.length; q < len3; q++) { domain = ref3[q]; types[domain.toNT()] = st; } } return this.transitiveClosure(types, this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#subClassOf'), false); } /** * Get all the Classes of which we can RDFS-infer the subject is a member * todo: This will loop is there is a class subclass loop (Sublass loops are * not illegal) * Returns a hash table where key is NT of type and value is statement why we * think so. * Does NOT return terms, returns URI strings. * We use NT representations in this version because they handle blank nodes. * @param subject - A subject node */ findTypeURIs(subject) { return this.NTtoURI(this.findTypesNT(subject)); } /** Trace statements which connect directly, or through bnodes * * @param subject - The node to start looking for statments * @param doc - The document to be searched, or null to search all documents * @returns an array of statements, duplicate statements are suppresssed. */ connectedStatements(subject, doc, excludePredicateURIs) { excludePredicateURIs = excludePredicateURIs || []; let todo = [subject]; let done = {}; let doneArcs = {}; let result = []; let self = this; let follow = function (x) { let queue = function (x) { if (x.termType === 'BlankNode' && !done[x.value]) { done[x.value] = true; todo.push(x); } }; let sts = self.statementsMatching(null, null, x, doc).concat(self.statementsMatching(x, null, null, doc)); sts = sts.filter(function (st) { if (excludePredicateURIs[st.predicate.value]) return false; let hash = st.toNT(); if (doneArcs[hash]) return false; doneArcs[hash] = true; return true; }); sts.forEach(function (st) { queue(st.subject); queue(st.object); }); result = result.concat(sts); }; while (todo.length) { follow(todo.shift()); } return result; } /** * Creates a new empty formula * * @param _features - Not applicable, but necessary for typing to pass */ formula(_features) { return new Formula(); } /** * Transforms an NTriples string format into a Node. * The blank node bit should not be used on program-external values; designed * for internal work such as storing a blank node id in an HTML attribute. * This will only parse the strings generated by the various toNT() methods. */ fromNT(str) { let dt, k, lang; switch (str[0]) { case '<': return this.sym(str.slice(1, -1)); case '"': lang = void 0; dt = void 0; k = str.lastIndexOf('"'); if (k < str.length - 1) { if (str[k + 1] === '@') { lang = str.slice(k + 2); } else if (str.slice(k + 1, k + 3) === '^^') { dt = this.fromNT(str.slice(k + 3)); } else { throw new Error("Can't convert string from NT: " + str); } } str = str.slice(1, k); str = str.replace(/\\"/g, '"'); str = str.replace(/\\n/g, '\n'); str = str.replace(/\\\\/g, '\\'); return this.rdfFactory.literal(str, lang || dt); case '_': return this.rdfFactory.blankNode(str.slice(2)); case '?': return new _variable.default(str.slice(1)); } throw new Error("Can't convert from NT: " + str); } /** Returns true if this formula holds the specified statement(s) */ holds(s, p, o, g) { let i; if (arguments.length === 1) { if (!s) { return true; } if (s instanceof Array) { for (i = 0; i < s.length; i++) { if (!this.holds(s[i])) { return false; } } return true; } else if ((0, _terms.isStatement)(s)) { return this.holds(s.subject, s.predicate, s.object, s.graph); } else if (s.statements) { return this.holds(s.statements); } } let st = this.anyStatementMatching(s, p, o, g); return st != null; } /** * Returns true if this formula holds the specified {statement} */ holdsStatement(statement) { return this.holds(statement.subject, statement.predicate, statement.object, statement.graph); } /** * Used by the n3parser to generate list elements * @param values - The values of the collection * @param context - The store * @return {BlankNode|Collection} - The term for the statement */ list(values, context) { if (context.rdfFactory.supports["COLLECTIONS"]) { const collection = context.rdfFactory.collection(); values.forEach(function (val) { collection.append(val); }); return collection; } else { const node = context.rdfFactory.blankNode(); const statements = (0, _utils.arrayToStatements)(context.rdfFactory, node, values); context.addAll(statements); return node; } } /** * Transform a collection of NTriple URIs into their URI strings * @param t - Some iterable collection of NTriple URI strings * @return A collection of the URIs as strings * todo: explain why it is important to go through NT */ NTtoURI(t) { let k, v; let uris = {}; for (k in t) { if (!t.hasOwnProperty(k)) continue; v = t[k]; if (k[0] === '<') { uris[k.slice(1, -1)] = v; } } return uris; } /** * Serializes this formula * @param base - The base string * @param contentType - The content type of the syntax to use * @param provenance - The provenance URI * @param options - options to pass to the serializer, as defined in serialize method */ serialize(base, contentType, provenance, options) { // delegate the graph serialization to the implementation in ./serialize return (0, _serialize.default)(provenance, this, base, contentType, undefined, options); } /** * Creates a new formula with the substituting bindings applied * @param bindings - The bindings to substitute */ substitute(bindings) { let statementsCopy = this.statements.map(function (ea) { return ea.substitute(bindings); }); // console.log('Formula subs statmnts:' + statementsCopy) const y = new Formula(); y.addAll(statementsCopy); // console.log('indexed-form subs formula:' + y) return y; } sym(uri, name) { if (name) { throw new Error('This feature (kb.sym with 2 args) is removed. Do not assume prefix mappings.'); } return this.rdfFactory.namedNode(uri); } /** * Gets the node matching the specified pattern. Throws when no match could be made. * @param s - The subject * @param p - The predicate * @param o - The object * @param g - The graph that contains the statement */ the(s, p, o, g) { let x = this.any(s, p, o, g); if (x == null) { _log.default.error('No value found for the() {' + s + ' ' + p + ' ' + o + '}.'); } return x; } /** * RDFS Inference * These are hand-written implementations of a backward-chaining reasoner * over the RDFS axioms. * @param seeds - A hash of NTs of classes to start with * @param predicate - The property to trace though * @param inverse - Trace inverse direction */ transitiveClosure(seeds, predicate, inverse) { let elt, i, len, s, sups, t; let agenda = {}; Object.assign(agenda, seeds); // make a copy let done = {}; // classes we have looked up while (true) { t = function () { for (let p in agenda) { if (!agenda.hasOwnProperty(p)) continue; return p; } }(); if (t == null) { return done; } sups = inverse ? this.each(void 0, predicate, this.fromNT(t)) : this.each(this.fromNT(t), predicate); for (i = 0, len = sups.length; i < len; i++) { elt = sups[i]; s = elt.toNT(); if (s in done) { continue; } if (s in agenda) { continue; } agenda[s] = agenda[t]; } done[t] = agenda[t]; delete agenda[t]; } } /** * Finds the types in the list which have no *stored* supertypes * We exclude the universal class, owl:Things and rdf:Resource, as it is * information-free. * @param types - The types */ topTypeURIs(types) { let i; let j; let k; let len; let n; let ref; let tops; let v; tops = []; for (k in types) { if (!types.hasOwnProperty(k)) continue; v = types[k]; n = 0; ref = this.each(this.rdfFactory.namedNode(k), this.rdfFactory.namedNode('http://www.w3.org/2000/01/rdf-schema#subClassOf')); for (i = 0, len = ref.length; i < len; i++) { j = ref[i]; if (j.uri !== 'http://www.w3.org/2000/01/rdf-schema#Resource') { n++; break; } } if (!n) { tops[k] = v; } } if (tops['http://www.w3.org/2000/01/rdf-schema#Resource']) { delete tops['http://www.w3.org/2000/01/rdf-schema#Resource']; } if (tops['http://www.w3.org/2002/07/owl#Thing']) { delete tops['http://www.w3.org/2002/07/owl#Thing']; } return tops; } /** * Serializes this formula to a string */ toString() { return '{' + this.statements.join('\n') + '}'; } /** * Gets a new variable * @param name - The variable's name */ variable(name) { return new _variable.default(name); } /** * Gets the number of statements in this formula that matches the specified pattern * @param s - The subject * @param p - The predicate * @param o - The object * @param g - The graph that contains the statement */ whether(s, p, o, g) { return this.statementsMatching(s, p, o, g, false).length; } } exports.default = Formula;