/* 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"];
const {XPCOMUtils} = ChromeUtils.import("resource://gre/modules/XPCOMUtils.jsm");
XPCOMUtils.defineLazyGlobalGetters(this, ["DOMParser", "Element", "XMLSerializer", "fetch"]);
ChromeUtils.defineModuleGetter(this, "OS",
"resource://gre/modules/osfile.jsm");
ChromeUtils.defineModuleGetter(this, "Services",
"resource://gre/modules/Services.jsm");
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.
*/
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 = `\n\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.
*/
_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 OS.File.writeAtomic(file, new TextEncoder().encode(this.serializeToString()));
}
}