rdf-dataset-fragmenter/lib/io/QuadSinkCsv.js

Fragments an RDF dataset into multiple parts

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.QuadSinkCsv = void 0;
const fs = require("node:fs");
const node_path_1 = require("node:path");
const mkdirp_1 = require("mkdirp");
const rdf_string_1 = require("rdf-string");
/**
 * A quad sink that writes quads to a CSV file.
 */
class QuadSinkCsv {
    /**
     * @param file The file to write to.
     * @param columns The quad term names that will be serialized as columns.
     */
    constructor(file, columns) {
        this.file = file;
        this.columns = columns;
    }
    close() {
        return new Promise((resolve, reject) => {
            if (this.fileStream) {
                this.fileStream.close((error) => {
                    if (error) {
                        return reject(error);
                    }
                    return resolve();
                });
            }
            else {
                resolve();
            }
        });
    }
    async push(iri, quad) {
        if (!this.fileStream) {
            // Ensure output directory exists
            const folder = (0, node_path_1.dirname)(this.file);
            await (0, mkdirp_1.mkdirp)(folder);
            // Open file stream
            this.fileStream = fs.createWriteStream(this.file);
            await new Promise((resolve) => {
                this.fileStream.on('open', () => {
                    // Write CSV header
                    this.fileStream.write(`${this.columns.join(',')}\n`);
                    resolve();
                });
            });
        }
        this.fileStream.write(`${this.columns.map(column => (0, rdf_string_1.termToString)(quad[column])).join(',')}\n`);
    }
}
exports.QuadSinkCsv = QuadSinkCsv;
//# sourceMappingURL=QuadSinkCsv.js.map