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Diffstat (limited to 'legacy/RDFDataSource.sys.mjs')
| -rw-r--r-- | legacy/RDFDataSource.sys.mjs | 1511 |
1 files changed, 1511 insertions, 0 deletions
diff --git a/legacy/RDFDataSource.sys.mjs b/legacy/RDFDataSource.sys.mjs new file mode 100644 index 0000000..27687ba --- /dev/null +++ b/legacy/RDFDataSource.sys.mjs @@ -0,0 +1,1511 @@ + /* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/** + * This module creates a new API for accessing and modifying RDF graphs. The + * goal is to be able to serialise the graph in a human readable form. Also + * if the graph was originally loaded from an RDF/XML the serialisation should + * closely match the original with any new data closely following the existing + * layout. The output should always be compatible with Mozilla's RDF parser. + * + * This is all achieved by using a DOM Document to hold the current state of the + * graph in XML form. This can be initially loaded and parsed from disk or + * a blank document used for an empty graph. As assertions are added to the + * graph, appropriate DOM nodes are added to the document to represent them + * along with any necessary whitespace to properly layout the XML. + * + * In general the order of adding assertions to the graph will impact the form + * the serialisation takes. If a resource is first added as the object of an + * assertion then it will eventually be serialised inside the assertion's + * property element. If a resource is first added as the subject of an assertion + * then it will be serialised at the top level of the XML. + */ + +const NS_XML = "http://www.w3.org/XML/1998/namespace"; +const NS_XMLNS = "http://www.w3.org/2000/xmlns/"; +const NS_RDF = "http://www.w3.org/1999/02/22-rdf-syntax-ns#"; +const NS_NC = "http://home.netscape.com/NC-rdf#"; + +/* eslint prefer-template: 1 */ + +function raw(strings) { + return strings.raw[0].replace(/\s+/, ""); +} + +// Copied from http://www.w3.org/TR/2000/REC-xml-20001006#CharClasses +const XML_LETTER = raw` + \u0041-\u005A\u0061-\u007A\u00C0-\u00D6\u00D8-\u00F6 + \u00F8-\u00FF\u0100-\u0131\u0134-\u013E\u0141-\u0148 + \u014A-\u017E\u0180-\u01C3\u01CD-\u01F0\u01F4-\u01F5 + \u01FA-\u0217\u0250-\u02A8\u02BB-\u02C1\u0386\u0388-\u038A + \u038C\u038E-\u03A1\u03A3-\u03CE\u03D0-\u03D6\u03DA\u03DC + \u03DE\u03E0\u03E2-\u03F3\u0401-\u040C\u040E-\u044F + \u0451-\u045C\u045E-\u0481\u0490-\u04C4\u04C7-\u04C8 + \u04CB-\u04CC\u04D0-\u04EB\u04EE-\u04F5\u04F8-\u04F9 + \u0531-\u0556\u0559\u0561-\u0586\u05D0-\u05EA\u05F0-\u05F2 + \u0621-\u063A\u0641-\u064A\u0671-\u06B7\u06BA-\u06BE + \u06C0-\u06CE\u06D0-\u06D3\u06D5\u06E5-\u06E6\u0905-\u0939 + \u093D\u0958-\u0961\u0985-\u098C\u098F-\u0990\u0993-\u09A8 + \u09AA-\u09B0\u09B2\u09B6-\u09B9\u09DC-\u09DD\u09DF-\u09E1 + \u09F0-\u09F1\u0A05-\u0A0A\u0A0F-\u0A10\u0A13-\u0A28 + \u0A2A-\u0A30\u0A32-\u0A33\u0A35-\u0A36\u0A38-\u0A39 + \u0A59-\u0A5C\u0A5E\u0A72-\u0A74\u0A85-\u0A8B\u0A8D + \u0A8F-\u0A91\u0A93-\u0AA8\u0AAA-\u0AB0\u0AB2-\u0AB3 + \u0AB5-\u0AB9\u0ABD\u0AE0\u0B05-\u0B0C\u0B0F-\u0B10 + \u0B13-\u0B28\u0B2A-\u0B30\u0B32-\u0B33\u0B36-\u0B39 + \u0B3D\u0B5C-\u0B5D\u0B5F-\u0B61\u0B85-\u0B8A\u0B8E-\u0B90 + \u0B92-\u0B95\u0B99-\u0B9A\u0B9C\u0B9E-\u0B9F\u0BA3-\u0BA4 + \u0BA8-\u0BAA\u0BAE-\u0BB5\u0BB7-\u0BB9\u0C05-\u0C0C + \u0C0E-\u0C10\u0C12-\u0C28\u0C2A-\u0C33\u0C35-\u0C39 + \u0C60-\u0C61\u0C85-\u0C8C\u0C8E-\u0C90\u0C92-\u0CA8 + \u0CAA-\u0CB3\u0CB5-\u0CB9\u0CDE\u0CE0-\u0CE1\u0D05-\u0D0C + \u0D0E-\u0D10\u0D12-\u0D28\u0D2A-\u0D39\u0D60-\u0D61 + \u0E01-\u0E2E\u0E30\u0E32-\u0E33\u0E40-\u0E45\u0E81-\u0E82 + \u0E84\u0E87-\u0E88\u0E8A\u0E8D\u0E94-\u0E97\u0E99-\u0E9F + \u0EA1-\u0EA3\u0EA5\u0EA7\u0EAA-\u0EAB\u0EAD-\u0EAE\u0EB0 + \u0EB2-\u0EB3\u0EBD\u0EC0-\u0EC4\u0F40-\u0F47\u0F49-\u0F69 + \u10A0-\u10C5\u10D0-\u10F6\u1100\u1102-\u1103\u1105-\u1107 + \u1109\u110B-\u110C\u110E-\u1112\u113C\u113E\u1140\u114C + \u114E\u1150\u1154-\u1155\u1159\u115F-\u1161\u1163\u1165 + \u1167\u1169\u116D-\u116E\u1172-\u1173\u1175\u119E\u11A8 + \u11AB\u11AE-\u11AF\u11B7-\u11B8\u11BA\u11BC-\u11C2\u11EB + \u11F0\u11F9\u1E00-\u1E9B\u1EA0-\u1EF9\u1F00-\u1F15 + \u1F18-\u1F1D\u1F20-\u1F45\u1F48-\u1F4D\u1F50-\u1F57 + \u1F59\u1F5B\u1F5D\u1F5F-\u1F7D\u1F80-\u1FB4\u1FB6-\u1FBC + \u1FBE\u1FC2-\u1FC4\u1FC6-\u1FCC\u1FD0-\u1FD3\u1FD6-\u1FDB + \u1FE0-\u1FEC\u1FF2-\u1FF4\u1FF6-\u1FFC\u2126\u212A-\u212B + \u212E\u2180-\u2182\u3041-\u3094\u30A1-\u30FA\u3105-\u312C + \uAC00-\uD7A3\u4E00-\u9FA5\u3007\u3021-\u3029 +`; +const XML_DIGIT = raw` + \u0030-\u0039\u0660-\u0669\u06F0-\u06F9\u0966-\u096F + \u09E6-\u09EF\u0A66-\u0A6F\u0AE6-\u0AEF\u0B66-\u0B6F + \u0BE7-\u0BEF\u0C66-\u0C6F\u0CE6-\u0CEF\u0D66-\u0D6F + \u0E50-\u0E59\u0ED0-\u0ED9\u0F20-\u0F29 +`; +const XML_COMBINING = raw` + \u0300-\u0345\u0360-\u0361\u0483-\u0486\u0591-\u05A1 + \u05A3-\u05B9\u05BB-\u05BD\u05BF\u05C1-\u05C2\u05C4 + \u064B-\u0652\u0670\u06D6-\u06DC\u06DD-\u06DF\u06E0-\u06E4 + \u06E7-\u06E8\u06EA-\u06ED\u0901-\u0903\u093C\u093E-\u094C + \u094D\u0951-\u0954\u0962-\u0963\u0981-\u0983\u09BC\u09BE + \u09BF\u09C0-\u09C4\u09C7-\u09C8\u09CB-\u09CD\u09D7 + \u09E2-\u09E3\u0A02\u0A3C\u0A3E\u0A3F\u0A40-\u0A42 + \u0A47-\u0A48\u0A4B-\u0A4D\u0A70-\u0A71\u0A81-\u0A83 + \u0ABC\u0ABE-\u0AC5\u0AC7-\u0AC9\u0ACB-\u0ACD\u0B01-\u0B03 + \u0B3C\u0B3E-\u0B43\u0B47-\u0B48\u0B4B-\u0B4D\u0B56-\u0B57 + \u0B82-\u0B83\u0BBE-\u0BC2\u0BC6-\u0BC8\u0BCA-\u0BCD\u0BD7 + \u0C01-\u0C03\u0C3E-\u0C44\u0C46-\u0C48\u0C4A-\u0C4D + \u0C55-\u0C56\u0C82-\u0C83\u0CBE-\u0CC4\u0CC6-\u0CC8 + \u0CCA-\u0CCD\u0CD5-\u0CD6\u0D02-\u0D03\u0D3E-\u0D43 + \u0D46-\u0D48\u0D4A-\u0D4D\u0D57\u0E31\u0E34-\u0E3A + \u0E47-\u0E4E\u0EB1\u0EB4-\u0EB9\u0EBB-\u0EBC\u0EC8-\u0ECD + \u0F18-\u0F19\u0F35\u0F37\u0F39\u0F3E\u0F3F\u0F71-\u0F84 + \u0F86-\u0F8B\u0F90-\u0F95\u0F97\u0F99-\u0FAD\u0FB1-\u0FB7 + \u0FB9\u20D0-\u20DC\u20E1\u302A-\u302F\u3099\u309A +`; +const XML_EXTENDER = raw` + \u00B7\u02D0\u02D1\u0387\u0640\u0E46\u0EC6\u3005 + \u3031-\u3035\u309D-\u309E\u30FC-\u30FE +`; +const XML_NCNAMECHAR = String.raw`${XML_LETTER}${XML_DIGIT}\.\-_${XML_COMBINING}${XML_EXTENDER}`; +const XML_NCNAME = new RegExp(`^[${XML_LETTER}_][${XML_NCNAMECHAR}]*$`); + +const URI_SUFFIX = /[A-Za-z_][0-9A-Za-z\.\-_]*$/; +const INDENT = /\n([ \t]*)$/; +const RDF_LISTITEM = /^http:\/\/www.w3.org\/1999\/02\/22-rdf-syntax-ns#_\d+$/; + +const RDF_NODE_INVALID_TYPES = + ["RDF", "ID", "about", "bagID", "parseType", "resource", "nodeID", + "li", "aboutEach", "aboutEachPrefix"]; +const RDF_PROPERTY_INVALID_TYPES = + ["Description", "RDF", "ID", "about", "bagID", "parseType", "resource", + "nodeID", "aboutEach", "aboutEachPrefix"]; + +/** + * Whether to use properly namespaces attributes for rdf:about etc... + * When on this produces poor output in the event that the rdf namespace is the + * default namespace, and the parser recognises unnamespaced attributes and + * most of our rdf examples are unnamespaced so leaving off for the time being. + */ +const USE_RDFNS_ATTR = false; + +var EXPORTED_SYMBOLS = ["RDFLiteral", "RDFIntLiteral", "RDFDateLiteral", + "RDFBlankNode", "RDFResource", "RDFDataSource"]; + +function isAttr(obj) { + return obj && typeof obj == "object" && ChromeUtils.getClassName(obj) == "Attr"; +} +function isDocument(obj) { + return obj && typeof obj == "object" && obj.nodeType == Element.DOCUMENT_NODE; +} +function isElement(obj) { + return Element.isInstance(obj); +} +function isText(obj) { + return obj && typeof obj == "object" && ChromeUtils.getClassName(obj) == "Text"; +} + +/** + * Logs an error message to the error console + */ +function ERROR(str) { + Cu.reportError(str); +} + +function RDF_R(name) { + return NS_RDF + name; +} + +function renameNode(domnode, namespaceURI, qname) { + if (isElement(domnode)) { + var newdomnode = domnode.ownerDocument.createElementNS(namespaceURI, qname); + if ("listCounter" in domnode) + newdomnode.listCounter = domnode.listCounter; + domnode.replaceWith(newdomnode); + while (domnode.firstChild) + newdomnode.appendChild(domnode.firstChild); + for (let attr of domnode.attributes) { + domnode.removeAttributeNode(attr); + newdomnode.setAttributeNode(attr); + } + return newdomnode; + } else if (isAttr(domnode)) { + if (domnode.ownerElement.hasAttribute(namespaceURI, qname)) + throw new Error("attribute already exists"); + var attr = domnode.ownerDocument.createAttributeNS(namespaceURI, qname); + attr.value = domnode.value; + domnode.ownerElement.setAttributeNode(attr); + domnode.ownerElement.removeAttributeNode(domnode); + return attr; + } + throw new Error("cannot rename node of this type"); +} + +function predicateOrder(a, b) { + return a.getPredicate().localeCompare(b.getPredicate()); +} + +/** + * Returns either an rdf namespaced attribute or an un-namespaced attribute + * value. Returns null if neither exists, + */ +function getRDFAttribute(element, name) { + if (element.hasAttributeNS(NS_RDF, name)) + return element.getAttributeNS(NS_RDF, name); + if (element.hasAttribute(name)) + return element.getAttribute(name); + return undefined; +} + +/** + * Represents an assertion in the datasource + */ +class RDFAssertion { + constructor(subject, predicate, object) { + if (!(subject instanceof RDFSubject)) + throw new Error("subject must be an RDFSubject"); + + if (typeof(predicate) != "string") + throw new Error("predicate must be a string URI"); + + if (!(object instanceof RDFLiteral) && !(object instanceof RDFSubject)) + throw new Error("object must be a concrete RDFNode"); + + if (object instanceof RDFSubject && object._ds != subject._ds) + throw new Error("object must be from the same datasource as subject"); + + // The subject on this assertion, an RDFSubject + this._subject = subject; + // The predicate, a string + this._predicate = predicate; + // The object, an RDFNode + this._object = object; + // The datasource this assertion exists in + this._ds = this._subject._ds; + // Marks that _DOMnode is the subject's element + this._isSubjectElement = false; + // The DOM node that represents this assertion. Could be a property element, + // a property attribute or the subject's element for rdf:type + this._DOMNode = null; + } + + /** + * Adds content to _DOMnode to store this assertion in the DOM document. + */ + _applyToDOMNode() { + if (this._object instanceof RDFLiteral) + this._object._applyToDOMNode(this._ds, this._DOMnode); + else + this._object._addReferenceToElement(this._DOMnode); + } + + /** + * Returns the DOM Element linked to the subject that this assertion is + * attached to. + */ + _getSubjectElement() { + if (isAttr(this._DOMnode)) + return this._DOMnode.ownerElement; + if (this._isSubjectElement) + return this._DOMnode; + return this._DOMnode.parentNode; + } + + getSubject() { + return this._subject; + } + + getPredicate() { + return this._predicate; + } + + getObject() { + return this._object; + } +} + +class RDFNode { + equals(rdfnode) { + return (rdfnode.constructor === this.constructor && + rdfnode._value == this._value); + } +} + +/** + * A simple literal value + */ +class RDFLiteral extends RDFNode { + constructor(value) { + super(); + this._value = value; + } + + /** + * This stores the value of the literal in the given DOM node + */ + _applyToDOMNode(ds, domnode) { + if (isElement(domnode)) + domnode.textContent = this._value; + else if (isAttr(domnode)) + domnode.value = this._value; + else + throw new Error("cannot use this node for a literal"); + } + + getValue() { + return this._value; + } +} + +/** + * A literal that is integer typed. + */ +class RDFIntLiteral extends RDFLiteral { + constructor(value) { + super(parseInt(value)); + } + + /** + * This stores the value of the literal in the given DOM node + */ + _applyToDOMNode(ds, domnode) { + if (!isElement(domnode)) + throw new Error("cannot use this node for a literal"); + + RDFLiteral.prototype._applyToDOMNode.call(this, ds, domnode); + var prefix = ds._resolvePrefix(domnode, `${NS_NC}parseType`); + domnode.setAttributeNS(prefix.namespaceURI, prefix.qname, "Integer"); + } +} + +/** + * A literal that represents a date. + */ +class RDFDateLiteral extends RDFLiteral { + constructor(value) { + if (!(value instanceof Date)) + throw new Error("RDFDateLiteral must be constructed with a Date object"); + + super(value); + } + + /** + * This stores the value of the literal in the given DOM node + */ + _applyToDOMNode(ds, domnode) { + if (!isElement(domnode)) + throw new Error("cannot use this node for a literal"); + + domnode.textContent = this._value.getTime(); + var prefix = ds._resolvePrefix(domnode, `${NS_NC}parseType`); + domnode.setAttributeNS(prefix.namespaceURI, prefix.qname, "Date"); + } +} + +/** + * This is an RDF node that can be a subject so a resource or a blank node + */ +class RDFSubject extends RDFNode { + constructor(ds) { + super(); + // A lookup of the assertions with this as the subject. Keyed on predicate + this._assertions = {}; + // A lookup of the assertions with this as the object. Keyed on predicate + this._backwards = {}; + // The datasource this subject belongs to + this._ds = ds; + // The DOM elements in the document that represent this subject. Array of Element + this._elements = []; + } + + /** + * Creates a new Element in the document for holding assertions about this + * subject. The URI controls what tagname to use. + */ + _createElement(uri) { + // Seek an appropriate reference to this node to add this node under + var parent = null; + for (var p in this._backwards) { + for (let back of this._backwards[p]) { + // Don't add under an rdf:type + if (back.getPredicate() == RDF_R("type")) + continue; + // The assertion already has a child node, probably one of ours + if (back._DOMnode.firstChild) + continue; + parent = back._DOMnode; + var element = this._ds._addElement(parent, uri); + this._removeReferenceFromElement(parent); + break; + } + if (parent) + break; + } + + // No back assertions that are sensible to use + if (!parent) + element = this._ds._addElement(this._ds._document.documentElement, uri); + + element.listCounter = 1; + this._applyToElement(element); + this._elements.push(element); + return element; + } + + /** + * When a DOM node representing this subject is removed from the document + * we must remove the node and recreate any child assertions elsewhere. + */ + _removeElement(element) { + var pos = this._elements.indexOf(element); + if (pos < 0) + throw new Error("invalid element"); + this._elements.splice(pos, 1); + if (element.parentNode != element.ownerDocument.documentElement) + this._addReferenceToElement(element.parentNode); + this._ds._removeElement(element); + + // Find all the assertions that are represented here and create new + // nodes for them. + for (var predicate in this._assertions) { + for (let assertion of this._assertions[predicate]) { + if (assertion._getSubjectElement() == element) + this._createDOMNodeForAssertion(assertion); + } + } + } + + /** + * Creates a DOM node to represent the assertion in the document. If the + * assertion has rdf:type as the predicate then an attempt will be made to + * create a typed subject Element, otherwise a new property Element is + * created. For list items an attempt is made to find an appropriate container + * that an rdf:li element can be added to. + */ + _createDOMNodeForAssertion(assertion) { + let elements; + if (RDF_LISTITEM.test(assertion.getPredicate())) { + // Find all the containers + elements = this._elements.filter(function(element) { + return (element.namespaceURI == NS_RDF && (element.localName == "Seq" || + element.localName == "Bag" || + element.localName == "Alt")); + }); + if (elements.length > 0) { + // Look for one whose listCounter matches the item we want to add + var item = parseInt(assertion.getPredicate().substring(NS_RDF.length + 1)); + for (let element of elements) { + if (element.listCounter == item) { + assertion._DOMnode = this._ds._addElement(element, RDF_R("li")); + assertion._applyToDOMNode(); + element.listCounter++; + return; + } + } + // No good container to add to, shove in the first real container + assertion._DOMnode = this._ds._addElement(elements[0], assertion.getPredicate()); + assertion._applyToDOMNode(); + return; + } + // TODO No containers, this will end up in a non-container for now + } else if (assertion.getPredicate() == RDF_R("type")) { + // Try renaming an existing rdf:Description + for (let element of this.elements) { + if (element.namespaceURI == NS_RDF && + element.localName == "Description") { + try { + var prefix = this._ds._resolvePrefix(element.parentNode, assertion.getObject().getURI()); + element = renameNode(element, prefix.namespaceURI, prefix.qname); + assertion._DOMnode = element; + assertion._isSubjectElement = true; + return; + } catch (e) { + // If the type cannot be sensibly turned into a prefix then just set + // as a regular property + } + } + } + } + + // Filter out all the containers + elements = this._elements.filter(function(element) { + return (element.namespaceURI != NS_RDF || (element.localName != "Seq" && + element.localName != "Bag" && + element.localName != "Alt")); + }); + if (elements.length == 0) { + // Create a new node of the right type + if (assertion.getPredicate() == RDF_R("type")) { + try { + assertion._DOMnode = this._createElement(assertion.getObject().getURI()); + assertion._isSubjectElement = true; + return; + } catch (e) { + // If the type cannot be sensibly turned into a prefix then just set + // as a regular property + } + } + elements[0] = this._createElement(RDF_R("Description")); + } + assertion._DOMnode = this._ds._addElement(elements[0], assertion.getPredicate()); + assertion._applyToDOMNode(); + } + + /** + * Removes the DOM node representing the assertion. + */ + _removeDOMNodeForAssertion(assertion) { + if (isAttr(assertion._DOMnode)) { + var parent = assertion._DOMnode.ownerElement; + parent.removeAttributeNode(assertion._DOMnode); + } else if (assertion._isSubjectElement) { + var domnode = renameNode(assertion._DOMnode, NS_RDF, "Description"); + if (domnode != assertion._DOMnode) { + var pos = this._elements.indexOf(assertion._DOMnode); + this._elements.splice(pos, 1, domnode); + } + parent = domnode; + } else { + var object = assertion.getObject(); + if (object instanceof RDFSubject && assertion._DOMnode.firstChild) { + // Object is a subject that has an Element inside this assertion's node. + for (let element of object._elements) { + if (element.parentNode == assertion._DOMnode) { + object._removeElement(element); + break; + } + } + } + parent = assertion._DOMnode.parentNode; + if (assertion._DOMnode.namespaceURI == NS_RDF && + assertion._DOMnode.localName == "li") + parent.listCounter--; + this._ds._removeElement(assertion._DOMnode); + } + + // If there are no assertions left using the assertion's containing dom node + // then remove it from the document. + // TODO could do with a quick lookup list for assertions attached to a node + for (var p in this._assertions) { + for (let assertion of this._assertions[p]) { + if (assertion._getSubjectElement() == parent) + return; + } + } + // No assertions left in this element. + this._removeElement(parent); + } + + /** + * Parses the given Element from the DOM document + */ + /* eslint-disable complexity */ + _parseElement(element) { + this._elements.push(element); + + // There might be an inferred rdf:type assertion in the element name + if (element.namespaceURI != NS_RDF || + element.localName != "Description") { + if (element.namespaceURI == NS_RDF && element.localName == "li") + throw new Error("rdf:li is not a valid type for a subject node"); + var assertion = new RDFAssertion(this, RDF_R("type"), + this._ds.getResource(element.namespaceURI + element.localName)); + assertion._DOMnode = element; + assertion._isSubjectElement = true; + this._addAssertion(assertion); + } + + // Certain attributes can be literal properties + for (let attr of element.attributes) { + if (attr.namespaceURI == NS_XML || attr.namespaceURI == NS_XMLNS || + attr.nodeName == "xmlns") + continue; + if ((attr.namespaceURI == NS_RDF || !attr.namespaceURI) && + (["nodeID", "about", "resource", "ID", "parseType"].includes(attr.localName))) + continue; + var object = null; + if (attr.namespaceURI == NS_RDF) { + if (attr.localName == "type") + object = this._ds.getResource(attr.nodeValue); + else if (attr.localName == "li") + throw new Error("rdf:li is not allowed as a property attribute"); + else if (attr.localName == "aboutEach") + throw new Error("rdf:aboutEach is deprecated"); + else if (attr.localName == "aboutEachPrefix") + throw new Error("rdf:aboutEachPrefix is deprecated"); + else if (attr.localName == "aboutEach") + throw new Error("rdf:aboutEach is deprecated"); + else if (attr.localName == "bagID") + throw new Error("rdf:bagID is deprecated"); + } + if (!object) + object = new RDFLiteral(attr.nodeValue); + assertion = new RDFAssertion(this, attr.namespaceURI + attr.localName, object); + assertion._DOMnode = attr; + this._addAssertion(assertion); + } + + var child = element.firstChild; + element.listCounter = 1; + while (child) { + if (isText(child) && /\S/.test(child.nodeValue)) { + ERROR(`Text ${child.nodeValue} is not allowed in a subject node`); + throw new Error("subject nodes cannot contain text content"); + } else if (isElement(child)) { + object = null; + var predicate = child.namespaceURI + child.localName; + if (child.namespaceURI == NS_RDF) { + if (RDF_PROPERTY_INVALID_TYPES.includes(child.localName) && + !child.localName.match(/^_\d+$/)) + throw new Error(`${child.nodeName} is an invalid property`); + if (child.localName == "li") { + predicate = RDF_R(`_${element.listCounter}`); + element.listCounter++; + } + } + + // Check for and bail out on unknown attributes on the property element + for (let attr of child.attributes) { + // Ignore XML namespaced attributes + if (attr.namespaceURI == NS_XML) + continue; + // These are reserved by XML for future use + if (attr.localName.substring(0, 3).toLowerCase() == "xml") + continue; + // We can handle these RDF attributes + if ((!attr.namespaceURI || attr.namespaceURI == NS_RDF) && + ["resource", "nodeID"].includes(attr.localName)) + continue; + // This is a special attribute we handle for compatibility with Mozilla RDF + if (attr.namespaceURI == NS_NC && + attr.localName == "parseType") + continue; + throw new Error(`Attribute ${attr.nodeName} is not supported`); + } + + var parseType = child.getAttributeNS(NS_NC, "parseType"); + if (parseType && parseType != "Date" && parseType != "Integer") { + ERROR(`parseType ${parseType} is not supported`); + throw new Error("unsupported parseType"); + } + + var resource = getRDFAttribute(child, "resource"); + var nodeID = getRDFAttribute(child, "nodeID"); + if ((resource && (nodeID || parseType)) || + (nodeID && (resource || parseType))) { + ERROR("Cannot use more than one of parseType, resource and nodeID on a single node"); + throw new Error("Invalid rdf assertion"); + } + + if (resource !== undefined) { + var base = Services.io.newURI(element.baseURI); + object = this._ds.getResource(base.resolve(resource)); + } else if (nodeID !== undefined) { + if (!nodeID.match(XML_NCNAME)) + throw new Error("rdf:nodeID must be a valid XML name"); + object = this._ds.getBlankNode(nodeID); + } else { + var hasText = false; + var childElement = null; + var subchild = child.firstChild; + while (subchild) { + if (isText(subchild) && /\S/.test(subchild.nodeValue)) { + hasText = true; + } else if (isElement(subchild)) { + if (childElement) { + new Error(`Multiple object elements found in ${child.nodeName}`); + } + childElement = subchild; + } + subchild = subchild.nextSibling; + } + + if ((resource || nodeID) && (hasText || childElement)) { + ERROR("Assertion references a resource so should not contain additional contents"); + throw new Error("assertion cannot contain multiple objects"); + } + + if (hasText && childElement) { + ERROR(`Both literal and resource objects found in ${child.nodeName}`); + throw new Error("assertion cannot contain multiple objects"); + } + + if (childElement) { + if (parseType) { + ERROR("Cannot specify a parseType for an assertion with resource object"); + throw new Error("parseType is not valid in this context"); + } + object = this._ds._getSubjectForElement(childElement); + object._parseElement(childElement); + } else if (parseType == "Integer") { + object = new RDFIntLiteral(child.textContent); + } else if (parseType == "Date") { + object = new RDFDateLiteral(new Date(child.textContent)); + } else { + object = new RDFLiteral(child.textContent); + } + } + + assertion = new RDFAssertion(this, predicate, object); + this._addAssertion(assertion); + assertion._DOMnode = child; + } + child = child.nextSibling; + } + } + /* eslint-enable complexity */ + + /** + * Adds a new assertion to the internal hashes. Should be called for every + * new assertion parsed or created programmatically. + */ + _addAssertion(assertion) { + var predicate = assertion.getPredicate(); + if (predicate in this._assertions) + this._assertions[predicate].push(assertion); + else + this._assertions[predicate] = [ assertion ]; + + var object = assertion.getObject(); + if (object instanceof RDFSubject) { + // Create reverse assertion + if (predicate in object._backwards) + object._backwards[predicate].push(assertion); + else + object._backwards[predicate] = [ assertion ]; + } + } + + /** + * Removes an assertion from the internal hashes. Should be called for all + * assertions that are programmatically deleted. + */ + _removeAssertion(assertion) { + var predicate = assertion.getPredicate(); + if (predicate in this._assertions) { + var pos = this._assertions[predicate].indexOf(assertion); + if (pos >= 0) + this._assertions[predicate].splice(pos, 1); + if (this._assertions[predicate].length == 0) + delete this._assertions[predicate]; + } + + var object = assertion.getObject(); + if (object instanceof RDFSubject) { + // Delete reverse assertion + if (predicate in object._backwards) { + pos = object._backwards[predicate].indexOf(assertion); + if (pos >= 0) + object._backwards[predicate].splice(pos, 1); + if (object._backwards[predicate].length == 0) + delete object._backwards[predicate]; + } + } + } + + /** + * Returns the ordinal assertions from this subject in order. + */ + _getChildAssertions() { + var assertions = []; + for (var i in this._assertions) { + if (RDF_LISTITEM.test(i)) + assertions.push(...this._assertions[i]); + } + assertions.sort(predicateOrder); + return assertions; + } + + /** + * Compares this to another rdf node + */ + equals(rdfnode) { + // subjects are created by the datasource so no two objects ever correspond + // to the same one. + return this === rdfnode; + } + + /** + * Adds a new assertion with this as the subject + */ + assert(predicate, object) { + if (predicate == RDF_R("type") && !(object instanceof RDFResource)) + throw new Error("rdf:type must be an RDFResource"); + + var assertion = new RDFAssertion(this, predicate, object); + this._createDOMNodeForAssertion(assertion); + this._addAssertion(assertion); + } + + /** + * Removes an assertion matching the predicate and node given, if such an + * assertion exists. + */ + unassert(predicate, object) { + if (!(predicate in this._assertions)) + return; + + for (let assertion of this._assertions[predicate]) { + if (assertion.getObject().equals(object)) { + this._removeAssertion(assertion); + this._removeDOMNodeForAssertion(assertion); + return; + } + } + } + + /** + * Returns an array of all the predicates that exist in assertions from this + * subject. + */ + getPredicates() { + return Object.keys(this._assertions); + } + + /** + * Returns all objects in assertions with this subject and the given predicate. + */ + getObjects(predicate) { + if (predicate in this._assertions) + return Array.from(this._assertions[predicate], + i => i.getObject()); + + return []; + } + + /** + * Returns all of the ordinal children of this subject in order. + */ + getChildren() { + return Array.from(this._getChildAssertions(), + i => i.getObject()); + } + + /** + * Removes the child at the given index. This is the index based on the + * children returned from getChildren. Forces a reordering of the later + * children. + */ + removeChildAt(pos) { + if (pos < 0) + throw new Error("no such child"); + var assertions = this._getChildAssertions(); + if (pos >= assertions.length) + throw new Error("no such child"); + for (var i = pos; i < assertions.length; i++) { + this._removeAssertion(assertions[i]); + this._removeDOMNodeForAssertion(assertions[i]); + } + var index = 1; + if (pos > 0) + index = parseInt(assertions[pos - 1].getPredicate().substring(NS_RDF.length + 1)) + 1; + for (let i = pos + 1; i < assertions.length; i++) { + assertions[i]._predicate = RDF_R(`_${index}`); + this._addAssertion(assertions[i]); + this._createDOMNodeForAssertion(assertions[i]); + index++; + } + } + + /** + * Removes the child with the given object. It is unspecified which child is + * removed if the object features more than once. + */ + removeChild(object) { + var assertions = this._getChildAssertions(); + for (var pos = 0; pos < assertions.length; pos++) { + if (assertions[pos].getObject().equals(object)) { + for (var i = pos; i < assertions.length; i++) { + this._removeAssertion(assertions[i]); + this._removeDOMNodeForAssertion(assertions[i]); + } + var index = 1; + if (pos > 0) + index = parseInt(assertions[pos - 1].getPredicate().substring(NS_RDF.length + 1)) + 1; + for (let i = pos + 1; i < assertions.length; i++) { + assertions[i]._predicate = RDF_R(`_${index}`); + this._addAssertion(assertions[i]); + this._createDOMNodeForAssertion(assertions[i]); + index++; + } + return; + } + } + throw new Error("no such child"); + } + + /** + * Adds a new ordinal child to this subject. + */ + addChild(object) { + var max = 0; + for (var i in this._assertions) { + if (RDF_LISTITEM.test(i)) + max = Math.max(max, parseInt(i.substring(NS_RDF.length + 1))); + } + max++; + this.assert(RDF_R(`_${max}`), object); + } + + /** + * This reorders the child assertions to remove duplicates and gaps in the + * sequence. Generally this will move all children to be under the same + * container element and all represented as an rdf:li + */ + reorderChildren() { + var assertions = this._getChildAssertions(); + for (let assertion of assertions) { + this._removeAssertion(assertion); + this._removeDOMNodeForAssertion(assertion); + } + var index = 1; + for (let assertion of assertions) { + assertion._predicate = RDF_R(`_${index}`); + this._addAssertion(assertion); + this._createDOMNodeForAssertion(assertion); + index++; + } + } + + /** + * Returns the type of this subject or null if there is no specified type. + */ + getType() { + var type = this.getProperty(RDF_R("type")); + if (type && type instanceof RDFResource) + return type.getURI(); + return null; + } + + /** + * Tests if a property exists for the given predicate. + */ + hasProperty(predicate) { + return (predicate in this._assertions); + } + + /** + * Retrieves the first property value for the given predicate. + */ + getProperty(predicate) { + if (predicate in this._assertions) + return this._assertions[predicate][0].getObject(); + return null; + } + + /** + * Sets the property value for the given predicate, clearing any existing + * values. + */ + setProperty(predicate, object) { + // TODO optimise by replacing the first assertion and clearing the rest + this.clearProperty(predicate); + this.assert(predicate, object); + } + + /** + * Clears any existing properties for the given predicate. + */ + clearProperty(predicate) { + if (!(predicate in this._assertions)) + return; + + var assertions = this._assertions[predicate]; + while (assertions.length > 0) { + var assertion = assertions[0]; + this._removeAssertion(assertion); + this._removeDOMNodeForAssertion(assertion); + } + } +} + +/** + * Creates a new RDFResource for the datasource. Private. + */ +class RDFResource extends RDFSubject { + constructor(ds, uri) { + if (!(ds instanceof RDFDataSource)) + throw new Error("datasource must be an RDFDataSource"); + + if (!uri) + throw new Error("An RDFResource requires a non-null uri"); + + super(ds); + // This is the uri that the resource represents. + this._uri = uri; + } + + /** + * Sets attributes on the DOM element to mark it as representing this resource + */ + _applyToElement(element) { + if (USE_RDFNS_ATTR) { + var prefix = this._ds._resolvePrefix(element, RDF_R("about")); + element.setAttributeNS(prefix.namespaceURI, prefix.qname, this._uri); + } else { + element.setAttribute("about", this._uri); + } + } + + /** + * Adds a reference to this resource to the given property Element. + */ + _addReferenceToElement(element) { + if (USE_RDFNS_ATTR) { + var prefix = this._ds._resolvePrefix(element, RDF_R("resource")); + element.setAttributeNS(prefix.namespaceURI, prefix.qname, this._uri); + } else { + element.setAttribute("resource", this._uri); + } + } + + /** + * Removes any reference to this resource from the given property Element. + */ + _removeReferenceFromElement(element) { + if (element.hasAttributeNS(NS_RDF, "resource")) + element.removeAttributeNS(NS_RDF, "resource"); + if (element.hasAttribute("resource")) + element.removeAttribute("resource"); + } + + getURI() { + return this._uri; + } +} + +/** + * Creates a new blank node. Private. + */ +class RDFBlankNode extends RDFSubject { + constructor(ds, nodeID) { + if (!(ds instanceof RDFDataSource)) + throw new Error("datasource must be an RDFDataSource"); + + super(ds); + // The nodeID of this node. May be null if there is no ID. + this._nodeID = nodeID; + } + + /** + * Sets attributes on the DOM element to mark it as representing this node + */ + _applyToElement(element) { + if (!this._nodeID) + return; + if (USE_RDFNS_ATTR) { + var prefix = this._ds._resolvePrefix(element, RDF_R("nodeID")); + element.setAttributeNS(prefix.namespaceURI, prefix.qname, this._nodeID); + } else { + element.setAttribute("nodeID", this._nodeID); + } + } + + /** + * Creates a new Element in the document for holding assertions about this + * subject. The URI controls what tagname to use. + */ + _createNewElement(uri) { + // If there are already nodes representing this in the document then we need + // a nodeID to match them + if (!this._nodeID && this._elements.length > 0) { + this._ds._createNodeID(this); + for (let element of this._elements) + this._applyToElement(element); + } + + return super._createNewElement.call(uri); + } + + /** + * Adds a reference to this node to the given property Element. + */ + _addReferenceToElement(element) { + if (this._elements.length > 0 && !this._nodeID) { + // In document elsewhere already + // Create a node ID and update the other nodes referencing + this._ds._createNodeID(this); + for (let element of this._elements) + this._applyToElement(element); + } + + if (this._nodeID) { + if (USE_RDFNS_ATTR) { + let prefix = this._ds._resolvePrefix(element, RDF_R("nodeID")); + element.setAttributeNS(prefix.namespaceURI, prefix.qname, this._nodeID); + } else { + element.setAttribute("nodeID", this._nodeID); + } + } else { + // Add the empty blank node, this is generally right since further + // assertions will be added to fill this out + var newelement = this._ds._addElement(element, RDF_R("Description")); + newelement.listCounter = 1; + this._elements.push(newelement); + } + } + + /** + * Removes any reference to this node from the given property Element. + */ + _removeReferenceFromElement(element) { + if (element.hasAttributeNS(NS_RDF, "nodeID")) + element.removeAttributeNS(NS_RDF, "nodeID"); + if (element.hasAttribute("nodeID")) + element.removeAttribute("nodeID"); + } + + getNodeID() { + return this._nodeID; + } +} + +/** + * Creates a new RDFDataSource from the given document. The document will be + * changed as assertions are added and removed to the RDF. Pass a null document + * to start with an empty graph. + */ +export class RDFDataSource { + constructor(document) { + // All known resources, indexed on URI + this._resources = {}; + // All blank nodes + this._allBlankNodes = []; + // All blank nodes with IDs, indexed on ID + this._blankNodes = {}; + // Suggested prefixes to use for namespaces, index is prefix, value is namespaceURI. + this._prefixes = { + rdf: NS_RDF, + NC: NS_NC, + }; + + if (!document) { + // Creating a document through xpcom leaves out the xml prolog so just parse + // something small + var parser = Cc["@mozilla.org/xmlextras/domparser;1"]. + createInstance(Ci.nsIDOMParser); + var doctext = `<?xml version="1.0"?>\n<rdf:RDF xmlns:rdf="${NS_RDF}"/>\n`; + document = parser.parseFromString(doctext, "text/xml"); + } + // The underlying DOM document for this datasource + this._document = document; + this._parseDocument(); + } + + static loadFromString(text) { + let parser = new DOMParser(); + let document = parser.parseFromString(text, "application/xml"); + + return new this(document); + } + + static loadFromBuffer(buffer) { + let parser = new DOMParser(); + let document = parser.parseFromBuffer(new Uint8Array(buffer), "application/xml"); + + return new this(document); + } + + static async loadFromFile(uri) { + if (uri instanceof Ci.nsIFile) + uri = Services.io.newFileURI(uri); + else if (typeof(uri) == "string") + uri = Services.io.newURI(uri); + + let resp = await fetch(uri.spec); + return this.loadFromBuffer(await resp.arrayBuffer()); + } + + get uri() { + return this._document.documentURI; + } + + /** + * Creates a new nodeID for an unnamed blank node. Just node<number>. + */ + _createNodeID(blanknode) { + var i = 1; + while (`node${i}` in this._blankNodes) + i++; + blanknode._nodeID = `node${i}`; + this._blankNodes[blanknode._nodeID] = blanknode; + } + + /** + * Returns an rdf subject for the given DOM Element. If the subject has not + * been seen before a new one is created. + */ + _getSubjectForElement(element) { + if (element.namespaceURI == NS_RDF && + RDF_NODE_INVALID_TYPES.includes(element.localName)) + throw new Error(`${element.nodeName} is not a valid class for a subject node`); + + var about = getRDFAttribute(element, "about"); + var id = getRDFAttribute(element, "ID"); + var nodeID = getRDFAttribute(element, "nodeID"); + + if ((about && (id || nodeID)) || + (nodeID && (id || about))) { + ERROR("More than one of about, ID and nodeID present on the same subject"); + throw new Error("invalid subject in rdf"); + } + + if (about !== undefined) { + let base = Services.io.newURI(element.baseURI); + return this.getResource(base.resolve(about)); + } + if (id !== undefined) { + if (!id.match(XML_NCNAME)) + throw new Error("rdf:ID must be a valid XML name"); + let base = Services.io.newURI(element.baseURI); + return this.getResource(base.resolve(`#${id}`)); + } + if (nodeID !== undefined) + return this.getBlankNode(nodeID); + return this.getBlankNode(null); + } + + /** + * Parses the document for subjects at the top level. + */ + _parseDocument() { + if (!this._document.documentElement) { + ERROR("No document element in document"); + throw new Error("document contains no root element"); + } + + if (this._document.documentElement.namespaceURI != NS_RDF || + this._document.documentElement.localName != "RDF") { + ERROR(`${this._document.documentElement.nodeName} is not rdf:RDF`); + throw new Error("document does not appear to be RDF"); + } + + var domnode = this._document.documentElement.firstChild; + while (domnode) { + if (isText(domnode) && /\S/.test(domnode.nodeValue)) { + ERROR("RDF does not allow for text in the root of the document"); + throw new Error("invalid markup in document"); + } else if (isElement(domnode)) { + var subject = this._getSubjectForElement(domnode); + subject._parseElement(domnode); + } + domnode = domnode.nextSibling; + } + } + + /** + * Works out a sensible namespace prefix to use for the given uri. node should + * be the parent of where the element is to be inserted, or the node that an + * attribute is to be added to. This will recursively walk to the top of the + * document finding an already registered prefix that matches for the uri. + * If none is found a new prefix is registered. + * This returns an object with keys namespaceURI, prefix, localName and qname. + * Pass null or undefined for badPrefixes for the first call. + */ + _resolvePrefix(domnode, uri, badPrefixes) { + if (!badPrefixes) + badPrefixes = []; + + // No known prefix, try to create one from the lookup list + if (!domnode || isDocument(domnode)) { + for (let i in this._prefixes) { + if (badPrefixes.includes(i)) + continue; + if (this._prefixes[i] == uri.substring(0, this._prefixes[i].length)) { + var local = uri.substring(this._prefixes[i].length); + var test = URI_SUFFIX.exec(local); + // Remaining part of uri is a good XML Name + if (test && test[0] == local) { + this._document.documentElement.setAttributeNS(NS_XMLNS, `xmlns:${i}`, this._prefixes[i]); + return { + namespaceURI: this._prefixes[i], + prefix: i, + localName: local, + qname: i ? `${i}:${local}` : local, + }; + } + } + } + + // No match, make something up + test = URI_SUFFIX.exec(uri); + if (test) { + var namespaceURI = uri.substring(0, uri.length - test[0].length); + local = test[0]; + let i = 1; + while (badPrefixes.includes(`NS${i}`)) + i++; + this._document.documentElement.setAttributeNS(NS_XMLNS, `xmlns:NS${i}`, namespaceURI); + return { + namespaceURI, + prefix: `NS${i}`, + localName: local, + qname: `NS${i}:${local}`, + }; + } + // There is no end part of this URI that is an XML Name + throw new Error(`invalid node name: ${uri}`); + } + + for (let attr of domnode.attributes) { + // Not a namespace declaration, ignore this attribute + if (attr.namespaceURI != NS_XMLNS && attr.nodeName != "xmlns") + continue; + + var prefix = attr.prefix ? attr.localName : ""; + // Seen this prefix before, cannot use it + if (badPrefixes.includes(prefix)) + continue; + + // Namespace matches the start of the uri + if (attr.value == uri.substring(0, attr.value.length)) { + local = uri.substring(attr.value.length); + test = URI_SUFFIX.exec(local); + // Remaining part of uri is a good XML Name + if (test && test[0] == local) { + return { + namespaceURI: attr.value, + prefix, + localName: local, + qname: prefix ? `${prefix}:${local}` : local, + }; + } + } + + badPrefixes.push(prefix); + } + + // No prefix found here, move up the document + return this._resolvePrefix(domnode.parentNode, uri, badPrefixes); + } + + /** + * Guess the indent level within the given Element. The method looks for + * elements that are preceded by whitespace including a newline. The + * whitespace following the newline is presumed to be the indentation for the + * element. + * If the indentation cannot be guessed then it recurses up the document + * hierarchy until it can guess the indent or until the Document is reached. + */ + _guessIndent(element) { + // The indent at document level is 0 + if (!element || isDocument(element)) + return ""; + + // Check the text immediately preceding each child node. One could be + // a valid indent + var pretext = ""; + var child = element.firstChild; + while (child) { + if (isText(child)) { + pretext += child.nodeValue; + } else if (isElement(child)) { + var result = INDENT.exec(pretext); + if (result) + return result[1]; + pretext = ""; + } + child = child.nextSibling; + } + + // pretext now contains any trailing text in the element. This can be + // the indent of the end tag. If so add a little to it. + result = INDENT.exec(pretext); + if (result) + return `${result[1]} `; + + // Check the text immediately before this node + pretext = ""; + var sibling = element.previousSibling; + while (sibling && isText(sibling)) { + pretext += sibling.nodeValue; + sibling = sibling.previousSibling; + } + + // If there is a sensible indent then just add to it. + result = INDENT.exec(pretext); + if (result) + return `${result[1]} `; + + // Last chance, get the indent level for the tag above and add to it + return `${this._guessIndent(element.parentNode)} `; + } + + _addElement(parent, uri) { + var prefix = this._resolvePrefix(parent, uri); + var element = this._document.createElementNS(prefix.namespaceURI, prefix.qname); + + if (parent.lastChild) { + // We want to insert immediately after the last child element + var last = parent.lastChild; + while (last && isText(last)) + last = last.previousSibling; + // No child elements so insert at the start + if (!last) + last = parent.firstChild; + else + last = last.nextSibling; + + let indent = this._guessIndent(parent); + parent.insertBefore(this._document.createTextNode(`\n${indent}`), last); + parent.insertBefore(element, last); + } else { + // No children, must indent our element and the end tag + let indent = this._guessIndent(parent.parentNode); + parent.append(`\n${indent} `, element, `\n${indent}`); + } + return element; + } + + /** + * Removes the element from its parent. Should also remove surrounding + * white space as appropriate. + */ + _removeElement(element) { + var parent = element.parentNode; + var sibling = element.previousSibling; + // Drop any text nodes immediately preceding the element + while (sibling && isText(sibling)) { + var temp = sibling; + sibling = sibling.previousSibling; + parent.removeChild(temp); + } + + sibling = element.nextSibling; + // Drop the element + parent.removeChild(element); + + // If the next node after element is now the first child then element was + // the first child. If there are no other child elements then remove the + // remaining child nodes. + if (parent.firstChild == sibling) { + while (sibling && isText(sibling)) + sibling = sibling.nextSibling; + if (!sibling) { + // No other child elements + while (parent.lastChild) + parent.removeChild(parent.lastChild); + } + } + } + + /** + * Requests that a given prefix be used for the namespace where possible. + * This must be called before any assertions are made using the namespace + * and the registration will not override any existing prefix used in the + * document. + */ + registerPrefix(prefix, namespaceURI) { + this._prefixes[prefix] = namespaceURI; + } + + /** + * Gets a blank node. nodeID may be null and if so a new blank node is created. + * If a nodeID is given then the blank node with that ID is returned or created. + */ + getBlankNode(nodeID) { + if (nodeID && nodeID in this._blankNodes) + return this._blankNodes[nodeID]; + + if (nodeID && !nodeID.match(XML_NCNAME)) + throw new Error("rdf:nodeID must be a valid XML name"); + + var rdfnode = new RDFBlankNode(this, nodeID); + this._allBlankNodes.push(rdfnode); + if (nodeID) + this._blankNodes[nodeID] = rdfnode; + return rdfnode; + } + + /** + * Gets all blank nodes + */ + getAllBlankNodes() { + return this._allBlankNodes.slice(); + } + + /** + * Gets the resource for the URI. The resource is created if it has not been + * used already. + */ + getResource(uri) { + if (uri in this._resources) + return this._resources[uri]; + + var resource = new RDFResource(this, uri); + this._resources[uri] = resource; + return resource; + } + + /** + * Gets all resources that have been used. + */ + getAllResources() { + return Object.values(this._resources); + } + + /** + * Returns all blank nodes and resources + */ + getAllSubjects() { + return [...Object.values(this._resources), + ...this._allBlankNodes]; + } + + /** + * Saves the RDF/XML to a string. + */ + serializeToString() { + var serializer = new XMLSerializer(); + return serializer.serializeToString(this._document); + } + + /** + * Saves the RDF/XML to a file. + */ + async saveToFile(file) { + return IOUtils.writeUTF8(file, this.serializeToString()); + } +} |