"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.LanceDB = void 0; const vectordb_1 = require("vectordb"); const vectorstores_1 = require("@langchain/core/vectorstores"); const documents_1 = require("@langchain/core/documents"); /** * A wrapper for an open-source database for vector-search with persistent * storage. It simplifies retrieval, filtering, and management of * embeddings. */ class LanceDB extends vectorstores_1.VectorStore { constructor(embeddings, args) { super(embeddings, args || {}); Object.defineProperty(this, "table", { enumerable: true, configurable: true, writable: true, value: void 0 }); Object.defineProperty(this, "textKey", { enumerable: true, configurable: true, writable: true, value: void 0 }); Object.defineProperty(this, "uri", { enumerable: true, configurable: true, writable: true, value: void 0 }); Object.defineProperty(this, "tableName", { enumerable: true, configurable: true, writable: true, value: void 0 }); Object.defineProperty(this, "mode", { enumerable: true, configurable: true, writable: true, value: void 0 }); this.table = args?.table; this.embeddings = embeddings; this.textKey = args?.textKey || "text"; this.uri = args?.uri || "~/lancedb"; this.tableName = args?.tableName || "langchain"; this.mode = args?.mode || vectordb_1.WriteMode.Overwrite; } /** * Adds documents to the database. * @param documents The documents to be added. * @returns A Promise that resolves when the documents have been added. */ async addDocuments(documents) { const texts = documents.map(({ pageContent }) => pageContent); return this.addVectors(await this.embeddings.embedDocuments(texts), documents); } _vectorstoreType() { return "lancedb"; } /** * Adds vectors and their corresponding documents to the database. * @param vectors The vectors to be added. * @param documents The corresponding documents to be added. * @returns A Promise that resolves when the vectors and documents have been added. */ async addVectors(vectors, documents) { if (vectors.length === 0) { return; } if (vectors.length !== documents.length) { throw new Error(`Vectors and documents must have the same length`); } const data = []; for (let i = 0; i < documents.length; i += 1) { const record = { vector: vectors[i], [this.textKey]: documents[i].pageContent, }; Object.keys(documents[i].metadata).forEach((metaKey) => { record[metaKey] = documents[i].metadata[metaKey]; }); data.push(record); } if (!this.table) { const db = await (0, vectordb_1.connect)(this.uri); this.table = await db.createTable(this.tableName, data, { writeMode: this.mode, }); return; } await this.table.add(data); } /** * Performs a similarity search on the vectors in the database and returns * the documents and their scores. * @param query The query vector. * @param k The number of results to return. * @returns A Promise that resolves with an array of tuples, each containing a Document and its score. */ async similaritySearchVectorWithScore(query, k) { if (!this.table) { throw new Error("Table not found. Please add vectors to the table first."); } const results = await this.table.search(query).limit(k).execute(); const docsAndScore = []; results.forEach((item) => { const metadata = {}; Object.keys(item).forEach((key) => { if (key !== "vector" && key !== "score" && key !== this.textKey) { metadata[key] = item[key]; } }); docsAndScore.push([ new documents_1.Document({ pageContent: item[this.textKey], metadata, }), item.score, ]); }); return docsAndScore; } /** * Creates a new instance of LanceDB from texts. * @param texts The texts to be converted into documents. * @param metadatas The metadata for the texts. * @param embeddings The embeddings to be managed. * @param dbConfig The configuration for the LanceDB instance. * @returns A Promise that resolves with a new instance of LanceDB. */ static async fromTexts(texts, metadatas, embeddings, dbConfig) { const docs = []; for (let i = 0; i < texts.length; i += 1) { const metadata = Array.isArray(metadatas) ? metadatas[i] : metadatas; const newDoc = new documents_1.Document({ pageContent: texts[i], metadata, }); docs.push(newDoc); } return LanceDB.fromDocuments(docs, embeddings, dbConfig); } /** * Creates a new instance of LanceDB from documents. * @param docs The documents to be added to the database. * @param embeddings The embeddings to be managed. * @param dbConfig The configuration for the LanceDB instance. * @returns A Promise that resolves with a new instance of LanceDB. */ static async fromDocuments(docs, embeddings, dbConfig) { const instance = new this(embeddings, dbConfig); await instance.addDocuments(docs); return instance; } } exports.LanceDB = LanceDB;