@treecg/ldes-orchestrator
Version:
Fills the gaps that a Linked Data Platform (LDP) cannot do by itself for creating a Linked Data Event Stream (LDES) in LDP.
112 lines (111 loc) • 6.27 kB
JavaScript
;
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var __importDefault = (this && this.__importDefault) || function (mod) {
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Object.defineProperty(exports, "__esModule", { value: true });
exports.addRelation = exports.createEventStream = void 0;
var n3_1 = require("n3");
var rdf_parse_1 = __importDefault(require("rdf-parse"));
var Vocabularies_1 = require("./Vocabularies");
var namedNode = n3_1.DataFactory.namedNode;
var literal = n3_1.DataFactory.literal;
var storeStream = require("rdf-store-stream").storeStream;
var streamify = require('streamify-string');
/**
* Creates an LDES EventStream with the first relation
*
* @param shape Shape IRI
* @param treePath IRI of the SHACL path on which the value of the relations will act
* @param firstNodeName a string timestamp, which is the name the node of the first relation
* @param base The base IRI (without the root.ttl suffix)
* @returns {Promise<Store>}
*/
function createEventStream(shape, treePath, firstNodeName, base) {
return __awaiter(this, void 0, void 0, function () {
var eventStream, view, text, textStream, quadStream, store;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
eventStream = {
"@context": { '@vocab': Vocabularies_1.TREE.namespace },
"@id": "root.ttl#Collection",
"@type": [Vocabularies_1.LDES.EventStream],
shape: [{ "@id": shape }],
view: [{ "@id": "root.ttl" }]
};
view = {
"@context": { '@vocab': Vocabularies_1.TREE.namespace },
"@id": "root.ttl",
"@type": [Vocabularies_1.TREE.Node],
relation: []
};
text = JSON.stringify([eventStream, view]);
textStream = streamify(text);
quadStream = rdf_parse_1.default.parse(textStream, { contentType: 'application/ld+json', baseIRI: base });
return [4 /*yield*/, storeStream(quadStream)];
case 1:
store = _a.sent();
addRelation(store, treePath, Vocabularies_1.TREE.GreaterThanOrEqualToRelation, firstNodeName, base);
return [2 /*return*/, store];
}
});
});
}
exports.createEventStream = createEventStream;
/**
* Adds a relation (to a certain node) to an existing root Node
*
* @param store The store which consists of the current root node
* @param treePath The SHACL path to used to compare the relation with
* @param treeRelation The type of TREE relation
* @param newNode The node to where the relation points. MUST be a string representation of an ISO timestamp (e.g. "1638353126973")
* @param base The IRI of the container where the root is stored
*/
function addRelation(store, treePath, treeRelation, newNode, base) {
var relationNode = store.createBlankNode();
var dateTimeISO = new Date(Number(newNode)).toISOString();
var rootNode = "".concat(base, "root.ttl");
var firstNode = "".concat(base + newNode, "/");
store.addQuad(namedNode(rootNode), namedNode(Vocabularies_1.TREE.relation), relationNode);
store.addQuad(relationNode, namedNode(Vocabularies_1.RDF.type), namedNode(treeRelation));
store.addQuad(relationNode, namedNode(Vocabularies_1.TREE.node), namedNode(firstNode));
store.addQuad(relationNode, namedNode(Vocabularies_1.TREE.path), namedNode(treePath));
store.addQuad(relationNode, namedNode(Vocabularies_1.TREE.value), literal(dateTimeISO, namedNode(Vocabularies_1.XSD.dateTime)));
}
exports.addRelation = addRelation;