json-data-to-csv/dist/cjs/index.js

A TypeScript library to convert array of objects to CSV format with customizable delimiter

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.JsonToCsvError = void 0;
exports.parse = parse;
/**
 * Custom error class for JSON to CSV conversion errors
 */
class JsonToCsvError extends Error {
    constructor(message, code) {
        super(message);
        this.code = code;
        this.name = 'JsonToCsvError';
    }
}
exports.JsonToCsvError = JsonToCsvError;
/**
 * Escapes CSV field values that contain special characters
 * @param value - The value to escape
 * @param delimiter - The delimiter being used
 * @returns Escaped value
 */
function escapeCSVField(value, delimiter) {
    // If the value contains delimiter, newline, or double quote, wrap in quotes
    if (value.includes(delimiter) ||
        value.includes('\n') ||
        value.includes('\r') ||
        value.includes('"')) {
        // Escape any existing double quotes by doubling them
        const escapedValue = value.replace(/"/g, '""');
        return `"${escapedValue}"`;
    }
    return value;
}
/**
 * Converts a value to a string representation suitable for CSV
 * @param value - The value to convert
 * @returns String representation of the value
 */
function valueToString(value) {
    if (value === null || value === undefined) {
        return '';
    }
    if (typeof value === 'object') {
        try {
            return JSON.stringify(value);
        }
        catch (error) {
            throw new JsonToCsvError('Failed to serialize object value', 'SERIALIZATION_ERROR');
        }
    }
    return String(value);
}
/**
 * Parses an array of objects into CSV format
 * @param data - Array of objects to convert to CSV
 * @param options - Options for parsing (delimiter)
 * @returns CSV string with header row and data rows
 */
function parse(data, options = {}) {
    var _a;
    // Validate input
    if (!Array.isArray(data)) {
        throw new JsonToCsvError('Input data must be an array', 'INVALID_INPUT');
    }
    if (data.length === 0) {
        throw new JsonToCsvError('Input data cannot be empty', 'EMPTY_INPUT');
    }
    // Validate delimiter before applying default
    if (options.delimiter !== undefined &&
        (typeof options.delimiter !== 'string' || options.delimiter.length === 0)) {
        throw new JsonToCsvError('Delimiter must be a non-empty string', 'INVALID_DELIMITER');
    }
    const delimiter = (_a = options.delimiter) !== null && _a !== void 0 ? _a : ',';
    try {
        // Extract all unique keys from all objects to create comprehensive headers
        const allKeys = new Set();
        for (const row of data) {
            if (typeof row !== 'object' || row === null || Array.isArray(row)) {
                throw new JsonToCsvError('All data items must be objects', 'INVALID_DATA_TYPE');
            }
            Object.keys(row).forEach((key) => allKeys.add(key));
        }
        if (allKeys.size === 0) {
            throw new JsonToCsvError('No valid properties found in data objects', 'NO_PROPERTIES');
        }
        const headers = Array.from(allKeys);
        // Create CSV header row
        const headerRow = headers
            .map((header) => escapeCSVField(header, delimiter))
            .join(delimiter);
        // Create CSV data rows
        const dataRows = data.map((row, index) => {
            try {
                return headers
                    .map((header) => {
                    const value = valueToString(row[header]);
                    return escapeCSVField(value, delimiter);
                })
                    .join(delimiter);
            }
            catch (error) {
                throw new JsonToCsvError(`Error processing row ${index + 1}: ${error instanceof Error ? error.message : 'Unknown error'}`, 'ROW_PROCESSING_ERROR');
            }
        });
        // Combine header and data rows
        return [headerRow, ...dataRows].join('\n');
    }
    catch (error) {
        if (error instanceof JsonToCsvError) {
            throw error;
        }
        throw new JsonToCsvError(`Unexpected error during parsing: ${error instanceof Error ? error.message : 'Unknown error'}`, 'UNEXPECTED_ERROR');
    }
}