@maukode/siesvi/dist/siesvi.writer.js

siesvi is CSV library that use typescript and provide CSV common functions from parsing, validation, to transformation.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.CsvWriter = void 0;
const stream_1 = require("stream");
const fs_1 = require("fs");
class CsvWriter extends stream_1.Writable {
    constructor(options = {}) {
        super({ objectMode: true });
        this.columns = null;
        this.filePath = null;
        this.fileStream = null;
        this.outputBuffer = ''; // Store in-memory output if no filePath
        this.delimiter = options.delimiter || ',';
        this.includeHeader = options.includeHeader !== undefined ? options.includeHeader : true;
        this.filePath = options.filePath || null;
    }
    _construct(callback) {
        try {
            if (this.filePath) {
                this.fileStream = (0, fs_1.createWriteStream)(this.filePath, { flags: 'w' });
            }
            callback();
        }
        catch (error) {
            callback(error);
        }
    }
    _write(chunk, _, callback) {
        if (this.columns === null) {
            if (typeof chunk === 'object' && chunk !== null && !Array.isArray(chunk)) {
                this.columns = Object.keys(chunk);
                if (this.includeHeader) {
                    this.writeData(this.columns.join(this.delimiter) + '\n');
                }
            }
            else {
                return callback(new Error('First chunk must be an object to determine columns.'));
            }
        }
        if (typeof chunk === 'object' && chunk !== null && !Array.isArray(chunk)) {
            const rowValues = this.columns.map((col) => {
                let value = chunk[col]; // Access property dynamically
                if (typeof value === 'string') {
                    if (value.includes('"') || value.includes(this.delimiter)) {
                        value = `"${value.replace(/"/g, '""')}"`; // Escape double quotes
                    }
                }
                return value !== undefined && value !== null ? String(value) : ''; // Handle undefined/null
            });
            this.writeData(rowValues.join(this.delimiter) + '\n', callback);
        }
        else {
            callback(new Error('Chunk must be an object.'));
        }
    }
    writeData(data, callback) {
        if (this.fileStream) {
            if (!this.fileStream.write(data, callback)) {
                this.fileStream.once('drain', () => callback && callback()); // Wait for drain event if buffer is full
            }
        }
        else {
            this.outputBuffer += data;
            if (callback)
                callback();
        }
    }
    _final(callback) {
        if (this.fileStream) {
            this.fileStream.end(callback);
        }
        else {
            callback();
        }
    }
    getOutputBuffer() {
        return this.outputBuffer;
    }
}
exports.CsvWriter = CsvWriter;