@naturalcycles/nodejs-lib/dist/stream/transform/transformMapSimple.js

Standard library for Node.js

import { Transform } from 'node:stream';
import { ErrorMode } from '@naturalcycles/js-lib/error/errorMode.js';
/**
 * Simplest version of `transformMap`.
 * errorMode: IMMEDIATE
 * Sync mode.
 * Has 0 options to configure.
 * If you need any configuration - use transformMap or transformMapSync.
 * Sync (not async) version of transformMap.
 * Supposedly faster, for cases when async is not needed.
 */
export function transformMapSimple(mapper, opt = {}) {
    let index = -1;
    const { errorMode = ErrorMode.THROW_IMMEDIATELY, logger = console, objectMode = true, highWaterMark = 1, } = opt;
    return new Transform({
        objectMode,
        highWaterMark,
        transform(chunk, _, cb) {
            try {
                cb(null, mapper(chunk, ++index));
            }
            catch (err) {
                logger.error(err);
                if (errorMode === ErrorMode.SUPPRESS) {
                    cb(); // suppress the error
                }
                else {
                    // Emit the error
                    cb(err);
                }
            }
        },
    });
}