@pujansrt/data-genie/dist/writers/tsv-writer.d.ts

High performant ETL engine written in TypeScript

import { DataWriter, DataRecord } from '../core/interfaces';
/**
 * TSVWriter class for writing data records to a Tab-Separated Values (TSV) file.
 * It uses the 'csv-stringify' library, configured specifically for tab delimiters.
 * Records are written incrementally, and a header row can be included.
 */
export declare class TSVWriter implements DataWriter {
    private readonly filePath;
    private readonly outputStream;
    private stringifier;
    private headerWritten;
    private fieldNames;
    private hasFieldNamesInFirstRow;
    /**
     * Constructs a new TSVWriter.
     * @param filePath The path to the output TSV file.
     */
    constructor(filePath: string);
    /**
     * Specifies whether the first row written should be a header row containing the field names.
     * If true, `setFieldNames` can be used to explicitly define names, or they will be inferred
     * from the first record.
     * @param value True to write field names in the first row, false otherwise.
     * @returns The current TSVWriter instance for chaining.
     */
    setFieldNamesInFirstRow(value: boolean): this;
    /**
     * Explicitly sets the names of the fields. These names will be used for the header row
     * (if `hasFieldNamesInFirstRow` is true) and to determine the order of values from `DataRecord`s.
     * If not called, field names will be inferred from the first record's keys.
     * @param names A list of string names for the fields (column headers).
     * @returns The current TSVWriter instance for chaining.
     */
    setFieldNames(...names: string[]): this;
    /**
     * Writes a single data record to the TSV file.
     * Handles writing the header row if configured and not yet written.
     * @param record The DataRecord object to write.
     * @returns A Promise that resolves when the record has been written to the stream.
     */
    write(record: DataRecord): Promise<void>;
    /**
     * Writes all data records from an asynchronous iterable to the TSV file.
     * @param records An AsyncIterableIterator of DataRecord objects.
     * @returns A Promise that resolves when all records have been written.
     */
    writeAll(records: AsyncIterableIterator<DataRecord>): Promise<void>;
    /**
     * Closes the underlying write stream. This should be called when all data has been written
     * to ensure all buffered data is flushed to the file and resources are released.
     * @returns A Promise that resolves when the stream is closed.
     */
    close(): Promise<void>;
}