embeddings-js/dist/vectorDb/hnswlib-db.js

A NodeJS RAG framework to easily work with LLMs and custom datasets

import HNSWLib from 'hnswlib-node';
import createDebugMessages from 'debug';
export class HNSWDb {
    constructor() {
        Object.defineProperty(this, "debug", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: createDebugMessages('embedjs:vector:HNSWDb')
        });
        Object.defineProperty(this, "index", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: void 0
        });
        Object.defineProperty(this, "docCount", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: void 0
        });
        Object.defineProperty(this, "docMap", {
            enumerable: true,
            configurable: true,
            writable: true,
            value: void 0
        });
        this.docCount = 0;
        this.docMap = new Map();
    }
    async init({ dimensions }) {
        this.index = await new HNSWLib.HierarchicalNSW('cosine', dimensions);
        this.index.initIndex(0);
    }
    async insertChunks(chunks) {
        const needed = this.index.getCurrentCount() + chunks.length;
        this.index.resizeIndex(needed);
        for (const chunk of chunks) {
            this.docCount++;
            this.index.addPoint(chunk.vector, this.docCount);
            this.docMap.set(this.docCount, { pageContent: chunk.pageContent, metadata: chunk.metadata });
        }
        return chunks.length;
    }
    async similaritySearch(query, k) {
        k = Math.min(k, this.index.getCurrentCount());
        const result = this.index.searchKnn(query, k, (label) => this.docMap.has(label));
        return result.neighbors.map((label) => this.docMap.get(label));
    }
    async getVectorCount() {
        return this.index.getCurrentCount();
    }
    async deleteKeys(_uniqueLoaderId) {
        this.debug('deleteKeys is not supported by HNSWDb');
        return false;
    }
    async reset() {
        await this.init({ dimensions: this.index.getNumDimensions() });
    }
}