"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = void 0;
var _IRIs = _interopRequireDefault(require("./IRIs"));
var _N3DataFactory = _interopRequireWildcard(require("./N3DataFactory"));
var _N3Util = require("./N3Util");
function _getRequireWildcardCache(nodeInterop) { if (typeof WeakMap !== "function") return null; var cacheBabelInterop = new WeakMap(); var cacheNodeInterop = new WeakMap(); return (_getRequireWildcardCache = function (nodeInterop) { return nodeInterop ? cacheNodeInterop : cacheBabelInterop; })(nodeInterop); }
function _interopRequireWildcard(obj, nodeInterop) { if (!nodeInterop && obj && obj.__esModule) { return obj; } if (obj === null || typeof obj !== "object" && typeof obj !== "function") { return { default: obj }; } var cache = _getRequireWildcardCache(nodeInterop); if (cache && cache.has(obj)) { return cache.get(obj); } var newObj = {}; var hasPropertyDescriptor = Object.defineProperty && Object.getOwnPropertyDescriptor; for (var key in obj) { if (key !== "default" && Object.prototype.hasOwnProperty.call(obj, key)) { var desc = hasPropertyDescriptor ? Object.getOwnPropertyDescriptor(obj, key) : null; if (desc && (desc.get || desc.set)) { Object.defineProperty(newObj, key, desc); } else { newObj[key] = obj[key]; } } } newObj.default = obj; if (cache) { cache.set(obj, newObj); } return newObj; }
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
// **N3Writer** writes N3 documents.
const DEFAULTGRAPH = _N3DataFactory.default.defaultGraph();
const {
rdf,
xsd
} = _IRIs.default;
// Characters in literals that require escaping
const escape = /["\\\t\n\r\b\f\u0000-\u0019\ud800-\udbff]/,
escapeAll = /["\\\t\n\r\b\f\u0000-\u0019]|[\ud800-\udbff][\udc00-\udfff]/g,
escapedCharacters = {
'\\': '\\\\',
'"': '\\"',
'\t': '\\t',
'\n': '\\n',
'\r': '\\r',
'\b': '\\b',
'\f': '\\f'
};
// ## Placeholder class to represent already pretty-printed terms
class SerializedTerm extends _N3DataFactory.Term {
// Pretty-printed nodes are not equal to any other node
// (e.g., [] does not equal [])
equals() {
return false;
}
}
// ## Constructor
class N3Writer {
constructor(outputStream, options) {
// ### `_prefixRegex` matches a prefixed name or IRI that begins with one of the added prefixes
this._prefixRegex = /$0^/;
// Shift arguments if the first argument is not a stream
if (outputStream && typeof outputStream.write !== 'function') options = outputStream, outputStream = null;
options = options || {};
this._lists = options.lists;
// If no output stream given, send the output as string through the end callback
if (!outputStream) {
let output = '';
this._outputStream = {
write(chunk, encoding, done) {
output += chunk;
done && done();
},
end: done => {
done && done(null, output);
}
};
this._endStream = true;
} else {
this._outputStream = outputStream;
this._endStream = options.end === undefined ? true : !!options.end;
}
// Initialize writer, depending on the format
this._subject = null;
if (!/triple|quad/i.test(options.format)) {
this._lineMode = false;
this._graph = DEFAULTGRAPH;
this._prefixIRIs = Object.create(null);
options.prefixes && this.addPrefixes(options.prefixes);
if (options.baseIRI) {
this._baseMatcher = new RegExp(`^${escapeRegex(options.baseIRI)}${options.baseIRI.endsWith('/') ? '' : '[#?]'}`);
this._baseLength = options.baseIRI.length;
}
} else {
this._lineMode = true;
this._writeQuad = this._writeQuadLine;
}
}
// ## Private methods
// ### Whether the current graph is the default graph
get _inDefaultGraph() {
return DEFAULTGRAPH.equals(this._graph);
}
// ### `_write` writes the argument to the output stream
_write(string, callback) {
this._outputStream.write(string, 'utf8', callback);
}
// ### `_writeQuad` writes the quad to the output stream
_writeQuad(subject, predicate, object, graph, done) {
try {
// Write the graph's label if it has changed
if (!graph.equals(this._graph)) {
// Close the previous graph and start the new one
this._write((this._subject === null ? '' : this._inDefaultGraph ? '.\n' : '\n}\n') + (DEFAULTGRAPH.equals(graph) ? '' : `${this._encodeIriOrBlank(graph)} {\n`));
this._graph = graph;
this._subject = null;
}
// Don't repeat the subject if it's the same
if (subject.equals(this._subject)) {
// Don't repeat the predicate if it's the same
if (predicate.equals(this._predicate)) this._write(`, ${this._encodeObject(object)}`, done);
// Same subject, different predicate
else this._write(`;\n ${this._encodePredicate(this._predicate = predicate)} ${this._encodeObject(object)}`, done);
}
// Different subject; write the whole quad
else this._write(`${(this._subject === null ? '' : '.\n') + this._encodeSubject(this._subject = subject)} ${this._encodePredicate(this._predicate = predicate)} ${this._encodeObject(object)}`, done);
} catch (error) {
done && done(error);
}
}
// ### `_writeQuadLine` writes the quad to the output stream as a single line
_writeQuadLine(subject, predicate, object, graph, done) {
// Write the quad without prefixes
delete this._prefixMatch;
this._write(this.quadToString(subject, predicate, object, graph), done);
}
// ### `quadToString` serializes a quad as a string
quadToString(subject, predicate, object, graph) {
return `${this._encodeSubject(subject)} ${this._encodeIriOrBlank(predicate)} ${this._encodeObject(object)}${graph && graph.value ? ` ${this._encodeIriOrBlank(graph)} .\n` : ' .\n'}`;
}
// ### `quadsToString` serializes an array of quads as a string
quadsToString(quads) {
return quads.map(t => {
return this.quadToString(t.subject, t.predicate, t.object, t.graph);
}).join('');
}
// ### `_encodeSubject` represents a subject
_encodeSubject(entity) {
return entity.termType === 'Quad' ? this._encodeQuad(entity) : this._encodeIriOrBlank(entity);
}
// ### `_encodeIriOrBlank` represents an IRI or blank node
_encodeIriOrBlank(entity) {
// A blank node or list is represented as-is
if (entity.termType !== 'NamedNode') {
// If it is a list head, pretty-print it
if (this._lists && entity.value in this._lists) entity = this.list(this._lists[entity.value]);
return 'id' in entity ? entity.id : `_:${entity.value}`;
}
let iri = entity.value;
// Use relative IRIs if requested and possible
if (this._baseMatcher && this._baseMatcher.test(iri)) iri = iri.substr(this._baseLength);
// Escape special characters
if (escape.test(iri)) iri = iri.replace(escapeAll, characterReplacer);
// Try to represent the IRI as prefixed name
const prefixMatch = this._prefixRegex.exec(iri);
return !prefixMatch ? `<${iri}>` : !prefixMatch[1] ? iri : this._prefixIRIs[prefixMatch[1]] + prefixMatch[2];
}
// ### `_encodeLiteral` represents a literal
_encodeLiteral(literal) {
// Escape special characters
let value = literal.value;
if (escape.test(value)) value = value.replace(escapeAll, characterReplacer);
// Write a language-tagged literal
if (literal.language) return `"${value}"@${literal.language}`;
// Write dedicated literals per data type
if (this._lineMode) {
// Only abbreviate strings in N-Triples or N-Quads
if (literal.datatype.value === xsd.string) return `"${value}"`;
} else {
// Use common datatype abbreviations in Turtle or TriG
switch (literal.datatype.value) {
case xsd.string:
return `"${value}"`;
case xsd.boolean:
if (value === 'true' || value === 'false') return value;
break;
case xsd.integer:
if (/^[+-]?\d+$/.test(value)) return value;
break;
case xsd.decimal:
if (/^[+-]?\d*\.\d+$/.test(value)) return value;
break;
case xsd.double:
if (/^[+-]?(?:\d+\.\d*|\.?\d+)[eE][+-]?\d+$/.test(value)) return value;
break;
}
}
// Write a regular datatyped literal
return `"${value}"^^${this._encodeIriOrBlank(literal.datatype)}`;
}
// ### `_encodePredicate` represents a predicate
_encodePredicate(predicate) {
return predicate.value === rdf.type ? 'a' : this._encodeIriOrBlank(predicate);
}
// ### `_encodeObject` represents an object
_encodeObject(object) {
switch (object.termType) {
case 'Quad':
return this._encodeQuad(object);
case 'Literal':
return this._encodeLiteral(object);
default:
return this._encodeIriOrBlank(object);
}
}
// ### `_encodeQuad` encodes an RDF* quad
_encodeQuad({
subject,
predicate,
object,
graph
}) {
return `<<${this._encodeSubject(subject)} ${this._encodePredicate(predicate)} ${this._encodeObject(object)}${(0, _N3Util.isDefaultGraph)(graph) ? '' : ` ${this._encodeIriOrBlank(graph)}`}>>`;
}
// ### `_blockedWrite` replaces `_write` after the writer has been closed
_blockedWrite() {
throw new Error('Cannot write because the writer has been closed.');
}
// ### `addQuad` adds the quad to the output stream
addQuad(subject, predicate, object, graph, done) {
// The quad was given as an object, so shift parameters
if (object === undefined) this._writeQuad(subject.subject, subject.predicate, subject.object, subject.graph, predicate);
// The optional `graph` parameter was not provided
else if (typeof graph === 'function') this._writeQuad(subject, predicate, object, DEFAULTGRAPH, graph);
// The `graph` parameter was provided
else this._writeQuad(subject, predicate, object, graph || DEFAULTGRAPH, done);
}
// ### `addQuads` adds the quads to the output stream
addQuads(quads) {
for (let i = 0; i < quads.length; i++) this.addQuad(quads[i]);
}
// ### `addPrefix` adds the prefix to the output stream
addPrefix(prefix, iri, done) {
const prefixes = {};
prefixes[prefix] = iri;
this.addPrefixes(prefixes, done);
}
// ### `addPrefixes` adds the prefixes to the output stream
addPrefixes(prefixes, done) {
// Ignore prefixes if not supported by the serialization
if (!this._prefixIRIs) return done && done();
// Write all new prefixes
let hasPrefixes = false;
for (let prefix in prefixes) {
let iri = prefixes[prefix];
if (typeof iri !== 'string') iri = iri.value;
hasPrefixes = true;
// Finish a possible pending quad
if (this._subject !== null) {
this._write(this._inDefaultGraph ? '.\n' : '\n}\n');
this._subject = null, this._graph = '';
}
// Store and write the prefix
this._prefixIRIs[iri] = prefix += ':';
this._write(`@prefix ${prefix} <${iri}>.\n`);
}
// Recreate the prefix matcher
if (hasPrefixes) {
let IRIlist = '',
prefixList = '';
for (const prefixIRI in this._prefixIRIs) {
IRIlist += IRIlist ? `|${prefixIRI}` : prefixIRI;
prefixList += (prefixList ? '|' : '') + this._prefixIRIs[prefixIRI];
}
IRIlist = escapeRegex(IRIlist, /[\]\/\(\)\*\+\?\.\\\$]/g, '\\$&');
this._prefixRegex = new RegExp(`^(?:${prefixList})[^\/]*$|` + `^(${IRIlist})([_a-zA-Z][\\-_a-zA-Z0-9]*)$`);
}
// End a prefix block with a newline
this._write(hasPrefixes ? '\n' : '', done);
}
// ### `blank` creates a blank node with the given content
blank(predicate, object) {
let children = predicate,
child,
length;
// Empty blank node
if (predicate === undefined) children = [];
// Blank node passed as blank(Term("predicate"), Term("object"))
else if (predicate.termType) children = [{
predicate: predicate,
object: object
}];
// Blank node passed as blank({ predicate: predicate, object: object })
else if (!('length' in predicate)) children = [predicate];
switch (length = children.length) {
// Generate an empty blank node
case 0:
return new SerializedTerm('[]');
// Generate a non-nested one-triple blank node
case 1:
child = children[0];
if (!(child.object instanceof SerializedTerm)) return new SerializedTerm(`[ ${this._encodePredicate(child.predicate)} ${this._encodeObject(child.object)} ]`);
// Generate a multi-triple or nested blank node
default:
let contents = '[';
// Write all triples in order
for (let i = 0; i < length; i++) {
child = children[i];
// Write only the object is the predicate is the same as the previous
if (child.predicate.equals(predicate)) contents += `, ${this._encodeObject(child.object)}`;
// Otherwise, write the predicate and the object
else {
contents += `${(i ? ';\n ' : '\n ') + this._encodePredicate(child.predicate)} ${this._encodeObject(child.object)}`;
predicate = child.predicate;
}
}
return new SerializedTerm(`${contents}\n]`);
}
}
// ### `list` creates a list node with the given content
list(elements) {
const length = elements && elements.length || 0,
contents = new Array(length);
for (let i = 0; i < length; i++) contents[i] = this._encodeObject(elements[i]);
return new SerializedTerm(`(${contents.join(' ')})`);
}
// ### `end` signals the end of the output stream
end(done) {
// Finish a possible pending quad
if (this._subject !== null) {
this._write(this._inDefaultGraph ? '.\n' : '\n}\n');
this._subject = null;
}
// Disallow further writing
this._write = this._blockedWrite;
// Try to end the underlying stream, ensuring done is called exactly one time
let singleDone = done && ((error, result) => {
singleDone = null, done(error, result);
});
if (this._endStream) {
try {
return this._outputStream.end(singleDone);
} catch (error) {/* error closing stream */}
}
singleDone && singleDone();
}
}
// Replaces a character by its escaped version
exports.default = N3Writer;
function characterReplacer(character) {
// Replace a single character by its escaped version
let result = escapedCharacters[character];
if (result === undefined) {
// Replace a single character with its 4-bit unicode escape sequence
if (character.length === 1) {
result = character.charCodeAt(0).toString(16);
result = '\\u0000'.substr(0, 6 - result.length) + result;
}
// Replace a surrogate pair with its 8-bit unicode escape sequence
else {
result = ((character.charCodeAt(0) - 0xD800) * 0x400 + character.charCodeAt(1) + 0x2400).toString(16);
result = '\\U00000000'.substr(0, 10 - result.length) + result;
}
}
return result;
}
function escapeRegex(regex) {
return regex.replace(/[\]\/\(\)\*\+\?\.\\\$]/g, '\\$&');
} |