@maukode/siesvi/dist/siesvi.validator.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.CsvValidator = void 0;
const stream_1 = require("stream");
class CsvValidator extends stream_1.Transform {
    constructor(config = {}) {
        super({ objectMode: true });
        this.header = null;
        this.rowCount = 0;
        this.config = {
            delimiter: config.delimiter || ',',
            expectedHeader: config.expectedHeader,
            minColumns: config.minColumns,
            maxColumns: config.maxColumns,
        };
    }
    _transform(chunk, encoding, callback) {
        try {
            const lines = chunk.toString(encoding).split('\n').filter(line => line.trim() !== ''); // Remove empty lines
            for (const line of lines) {
                const row = line.split(this.config.delimiter);
                this.rowCount++;
                if (!this.header) {
                    this.header = row.map(header => header.trim()); // Trim headers
                    if (this.config.expectedHeader) {
                        if (this.config.expectedHeader.length !== this.header.length) {
                            return callback(new Error(`Header column count mismatch. Expected ${this.config.expectedHeader.length}, got ${this.header.length} on line ${this.rowCount}`));
                        }
                        for (let i = 0; i < this.config.expectedHeader.length; i++) {
                            if (this.config.expectedHeader[i].trim() !== this.header[i]) {
                                return callback(new Error(`Header mismatch at column ${i + 1}. Expected '${this.config.expectedHeader[i].trim()}', got '${this.header[i]}' on line ${this.rowCount}`));
                            }
                        }
                    }
                    continue;
                }
                if (this.config.minColumns !== undefined && row.length < this.config.minColumns) {
                    return callback(new Error(`Row ${this.rowCount} has too few columns. Expected at least ${this.config.minColumns}, got ${row.length}`));
                }
                if (this.config.maxColumns !== undefined && row.length > this.config.maxColumns) {
                    return callback(new Error(`Row ${this.rowCount} has too many columns. Expected at most ${this.config.maxColumns}, got ${row.length}`));
                }
                this.push(chunk);
            }
            callback();
        }
        catch (error) {
            callback(error);
        }
    }
}
exports.CsvValidator = CsvValidator;