@langchain/core/dist/documents/transformers.js

Core LangChain.js abstractions and schemas

import { Runnable } from "../runnables/base.js";
/**
 * Abstract base class for document transformation systems.
 *
 * A document transformation system takes an array of Documents and returns an
 * array of transformed Documents. These arrays do not necessarily have to have
 * the same length.
 *
 * One example of this is a text splitter that splits a large document into
 * many smaller documents.
 */
export class BaseDocumentTransformer extends Runnable {
    constructor() {
        super(...arguments);
        Object.defineProperty(this, "lc_namespace", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: ["langchain_core", "documents", "transformers"]
        });
    }
    /**
     * Method to invoke the document transformation. This method calls the
     * transformDocuments method with the provided input.
     * @param input The input documents to be transformed.
     * @param _options Optional configuration object to customize the behavior of callbacks.
     * @returns A Promise that resolves to the transformed documents.
     */
    invoke(input, _options) {
        return this.transformDocuments(input);
    }
}
/**
 * Class for document transformers that return exactly one transformed document
 * for each input document.
 */
export class MappingDocumentTransformer extends BaseDocumentTransformer {
    async transformDocuments(documents) {
        const newDocuments = [];
        for (const document of documents) {
            const transformedDocument = await this._transformDocument(document);
            newDocuments.push(transformedDocument);
        }
        return newDocuments;
    }
}