@barchart/common-node-js/aws/dynamo/schema/serialization/writers/CompositeWriter.js

Common classes, utilities, and functions for building Node.js servers

const assert = require('@barchart/common-js/lang/assert');

const Writer = require('./Writer');

module.exports = (() => {
	'use strict';

	/**
	 * An implementation of {@link Writer} that delegates to an array
	 * of {@link Writer} instances.
	 *
	 * @public
	 * @extends {Writer}
	 * @param {Writer[]} writers
	 */
	class CompositeWriter extends Writer {
		constructor(writers) {
			super();

			assert.argumentIsArray(writers, 'writers', Writer, 'Writer');

			this._writers = writers;
		}

		_write(source, target) {
			return this._writers.reduce((targetToUse, writer) => writer.write(source, targetToUse), target);
		}

		_canWrite(source, target) {
			return true;
		}

		toString() {
			return '[CompositeWriter]';
		}
	}

	return CompositeWriter;
})();