## File: README.md # Elasticsearch Node.js client [](http://standardjs.com/) [](https://buildkite.com/elastic/elasticsearch-javascript-client-integration-tests/builds?branch=main) [](https://github.com/elastic/elasticsearch-js/actions/workflows/nodejs.yml) [](https://codecov.io/gh/elastic/elasticsearch-js) [](https://www.npmjs.com/package/@elastic/elasticsearch) The official Node.js client for Elasticsearch. ## Try Elasticsearch and Kibana locally If you want to try Elasticsearch and Kibana locally, you can run the following command: ```bash curl -fsSL https://elastic.co/start-local | sh ``` This will run Elasticsearch at http://localhost:9200 and Kibana at http://localhost:5601. More information is available [here](https://www.elastic.co/guide/en/elasticsearch/reference/current/run-elasticsearch-locally.html). Alternatively, you can **[download the latest version of Elasticsearch](https://www.elastic.co/downloads/elasticsearch)** manually, or **[sign-up](https://cloud.elastic.co/registration?elektra=en-ess-sign-up-page) for a free trial of Elastic Cloud**. ## Installation Refer to the [Installation section](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_installation) of the getting started documentation. ## Connecting Refer to the [Connecting section](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_connecting) of the getting started documentation. ## Compatibility The Elasticsearch client is compatible with currently maintained JS versions. Language clients are forward compatible; meaning that clients support communicating with greater or equal minor versions of Elasticsearch without breaking. It does not mean that the client automatically supports new features of newer Elasticsearch versions; it is only possible after a release of a new client version. For example, a 8.12 client version won't automatically support the new features of the 8.13 version of Elasticsearch, the 8.13 client version is required for that. Elasticsearch language clients are only backwards compatible with default distributions and without guarantees made. | Elasticsearch Version | Elasticsearch-JS Branch | | --------------------- | ----------------------- | | main | main | | 9.x | 9.x | | 8.x | 8.x | | 7.x | 7.x | ## Usage - [Creating an index](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_creating_an_index) - [Indexing a document](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_indexing_documents) - [Getting documents](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_getting_documents) - [Searching documents](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_searching_documents) - [Updating documents](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_updating_documents) - [Deleting documents](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_deleting_documents) - [Deleting an index](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/getting-started-js.html#_deleting_an_index) ### Node.js support NOTE: The minimum supported version of Node.js is `v20`. The client versioning follows the Elastic Stack versioning, this means that major, minor, and patch releases are done following a precise schedule that often does not coincide with the [Node.js release](https://nodejs.org/en/about/releases/) times. To avoid support insecure and unsupported versions of Node.js, the client **will drop the support of EOL versions of Node.js between minor releases**. Typically, as soon as a Node.js version goes into EOL, the client will continue to support that version for at least another minor release. If you are using the client with a version of Node.js that will be unsupported soon, you will see a warning in your logs (the client will start logging the warning with two minors in advance). Unless you are **always** using a supported version of Node.js, we recommend defining the client dependency in your `package.json` with the `~` instead of `^`. In this way, you will lock the dependency on the minor release and not the major. (for example, `~7.10.0` instead of `^7.10.0`). | Node.js Version | Node.js EOL date | End of support | | --------------- | ---------------- | ------------------- | | `8.x` | `December 2019` | `7.11` (early 2021) | | `10.x` | `April 2021` | `7.12` (mid 2021) | | `12.x` | `April 2022` | `8.2` (early 2022) | | `14.x` | `April 2023` | `8.8` (early 2023) | | `16.x` | `September 2023` | `8.11` (late 2023) | | `18.x` | `April 2025` | `9.1` (mid 2025) | #### Browser > [!WARNING] > There is no official support for the browser environment. It exposes your Elasticsearch instance to everyone, which could lead to security issues. > We recommend that you write a lightweight proxy that uses this client instead, you can see a proxy example [here](./docs/examples/proxy). ## Documentation - [Introduction](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/introduction.html) - [Usage](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/client-connecting.html#client-usage) - [Client configuration](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/client-configuration.html) - [API reference](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/api-reference.html) - [Authentication](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/client-connecting.html#authentication) - [Observability](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/observability.html) - [Creating a child client](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/child.html) - [Client helpers](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/client-helpers.html) - [Typescript support](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/typescript.html) - [Testing](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/client-testing.html) - [Examples](https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/examples.html) ## Install multiple versions If you are using multiple versions of Elasticsearch, you need to use multiple versions of the client. In the past, install multiple versions of the same package was not possible, but with `npm v6.9`, you can do that via aliasing. The command you must run to install different version of the client is: ```sh npm install @npm:@elastic/elasticsearch@ ``` So for example if you need to install `7.x` and `6.x`, you will run: ```sh npm install es6@npm:@elastic/elasticsearch@6 npm install es7@npm:@elastic/elasticsearch@7 ``` And your `package.json` will look like the following: ```json "dependencies": { "es6": "npm:@elastic/elasticsearch@^6.7.0", "es7": "npm:@elastic/elasticsearch@^7.0.0" } ``` You will require the packages from your code by using the alias you have defined. ```js const { Client: Client6 } = require('es6') const { Client: Client7 } = require('es7') const client6 = new Client6({ cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' } }) const client7 = new Client7({ cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' } }) client6.info().then(console.log, console.log) client7.info().then(console.log, console.log) ``` Finally, if you want to install the client for the next version of Elasticsearch _(the one that lives in Elasticsearch’s main branch)_, you can use the following command: ```sh npm install esmain@github:elastic/elasticsearch-js ``` ## License This software is licensed under the [Apache License 2.0](./LICENSE). --- ## File: docs/examples/proxy/README.md # Elasticsearch proxy example This folder contains an example of how to build a lightweight proxy between your frontend code and Elasticsearch if you don't have a more sophisticated backend in place yet. > **IMPORTANT:** This is not a production ready code and it is only for demonstration purposes, > we make no guarantees on it's security and stability. This project is designed to be deployed on [Vercel](https://vercel.com/), a cloud platform for static sites and Serverless Functions. You can use other functions providers, such as [Google Cloud functions](https://cloud.google.com/functions). ## Project structure The project comes with four endpoints: - `/api/search`: runs a search, requires `'read'` permission - `/api/autocomplete`: runs an autocomplete suggestion, requires `'read'` permission - `/api/index`: indexes or updates a document, requires `'write'` permission - `/api/delete`: deletes a document, requires `'write'` permission Inside `utils/authorize.js` you can find the authorization logic for the endpoints. In each endpoint you should configure the `INDEX` variable. ## How to use Create an account on Vercel, then create a deployment on Elastic Cloud. If you don't have an account on Elastic Cloud, you can create one with a free 14-day trial of the [Elasticsearch Service](https://www.elastic.co/elasticsearch/service). ### Configure Elasticsearch Once you have created a deployment on Elastic Cloud copy the generated Cloud Id and the credentials. Then open `utils/prepare-elasticsearch.js` and fill your credentials. The script generates an [Api Key](https://www.elastic.co/guide/en/elasticsearch/reference/current/security-api-create-api-key.html) that you can use for authenticating your request. Based on the configuration of the Api Key, you will be able to perform different operation on the specified indices or index pattern. ### Configure Vercel Install the [Vercel CLI](https://vercel.com/docs/cli) to bootstrap the project, or read the [quickstart](https://vercel.com/docs) documentation. If you are using the CLI, bootstrap the project by running `vercel`. Test the project locally with `vercel dev`, and deploy it with `vercel deploy`. Configure the `ELASTIC_CLOUD_ID` [environment varible](https://vercel.com/docs/environment-variables) as well. The Api Key is passed from the frontend app via a `Authorization` header as `Bearer` token and is used to authorize the API calls to the endpoints as well. Additional configuration, such as CORS, can be added to [`vercel.json`](https://vercel.com/docs/configuration). ## Authentication If you are using Elasticsearch only for search purposes, such as a search box, you can create an Api Key with `read` permissions and store it in your frontend app. Then you can send it via `Authorization` header to the proxy and run your searches. If you need to ingest data as well, it's more secure to have a strong authentication in your application. For such cases, use an external authentication service, such as [Auth0](https://auth0.com/) or [Magic Link](https://magic.link/). Then create a different Api Key with `read` and `write` permissions for authenticated users, that will not be stored in the frontend app. ## License This software is licensed under the [Apache 2 license](../../LICENSE). --- ## File: docs/reference/advanced-config.md --- mapped_pages: - https://www.elastic.co/guide/en/elasticsearch/client/javascript-api/current/advanced-config.html --- # Advanced configuration [advanced-config] If you need to customize the client behavior heavily, you are in the right place! The client enables you to customize the following internals: * `ConnectionPool` class * `Connection` class * `Serializer` class ::::{note} For information about the `Transport` class, refer to [Transport](/reference/transport.md). :::: ## `ConnectionPool` [_connectionpool] This class is responsible for keeping in memory all the {{es}} connections that you are using. There is a single `Connection` for every node. The connection pool handles the resurrection strategies and the updates of the pool. ```js const { Client, ConnectionPool } = require('@elastic/elasticsearch') class MyConnectionPool extends ConnectionPool { markAlive (connection) { // your code super.markAlive(connection) } } const client = new Client({ ConnectionPool: MyConnectionPool, cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' } }) ``` ## `Connection` [_connection] This class represents a single node, it holds every information we have on the node, such as roles, id, URL, custom headers and so on. The actual HTTP request is performed here, this means that if you want to swap the default HTTP client ([Undici `Pool`](https://undici.nodejs.org/#/docs/api/Pool.md)), you should override the `request` method of this class. ```js const { Client, BaseConnection } = require('@elastic/elasticsearch') class MyConnection extends BaseConnection { request (params, callback) { // your code } } const client = new Client({ Connection: MyConnection, cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' } }) ``` `@elastic/transport` provides two `Connection` implementations: - `UndiciConnection`: manages HTTP connections using [Undici](https://undici.nodejs.org/), Node.js's high-performance HTTP client implementation; this is the default value of `Connection` and is recommended unless you have a use case that is not yet supported by Undici or `UndiciConnection` - `HttpConnection`: manages HTTP connections using [the `http` package](https://nodejs.org/api/http.html) from Node.js's standard library ## `Serializer` [_serializer] This class is responsible for the serialization of every request, it offers the following methods: * `serialize(object: any): string;` serializes request objects. * `deserialize(json: string): any;` deserializes response strings. * `ndserialize(array: any[]): string;` serializes bulk request objects. * `qserialize(object: any): string;` serializes request query parameters. * `encodeFloat32Vector(floats: number[]): string;` encodes a float array to base64 for efficient vector ingestion. * `decodeFloat32Vector(base64: string): number[];` decodes a base64 string back to a float array. ```js const { Client, Serializer } = require('@elastic/elasticsearch') class MySerializer extends Serializer { serialize (object) { // your code } } const client = new Client({ Serializer: MySerializer, cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' } }) ``` ## Redaction of potentially sensitive data [redaction] When the client raises an `Error` that originated at the HTTP layer, like a `ConnectionError` or `TimeoutError`, a `meta` object is often attached to the error object that includes metadata useful for debugging, like request and response information. Because this can include potentially sensitive data, like authentication secrets in an `Authorization` header, the client takes measures to redact common sources of sensitive data when this metadata is attached and serialized. If your configuration requires extra headers or other configurations that may include sensitive data, you may want to adjust these settings to account for that. By default, the `redaction` option is set to `{ type: 'replace' }`, which recursively searches for sensitive key names, case insensitive, and replaces their values with the string `[redacted]`. ```js const { Client } = require('@elastic/elasticsearch') const client = new Client({ cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' }, }) try { await client.indices.create({ index: 'my_index' }) } catch (err) { console.log(err.meta.meta.request.options.headers.authorization) // prints "[redacted]" } ``` If you would like to redact additional properties, you can include additional key names to search and replace: ```js const { Client } = require('@elastic/elasticsearch') const client = new Client({ cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' }, headers: { 'X-My-Secret-Password': 'shhh it's a secret!' }, redaction: { type: "replace", additionalKeys: ["x-my-secret-password"] } }) try { await client.indices.create({ index: 'my_index' }) } catch (err) { console.log(err.meta.meta.request.options.headers['X-My-Secret-Password']) // prints "[redacted]" } ``` Alternatively, if you know you’re not going to use the metadata at all, setting the redaction type to `remove` will remove all optional sources of potentially sensitive data entirely, or replacing them with `null` for required properties. ```js const { Client } = require('@elastic/elasticsearch') const client = new Client({ cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' }, redaction: { type: "remove" } }) try { await client.indices.create({ index: 'my_index' }) } catch (err) { console.log(err.meta.meta.request.options.headers) // undefined } ``` Finally, if you prefer to turn off redaction altogether, perhaps while debugging on a local developer environment, you can set the redaction type to `off`. This will revert the client to pre-8.11.0 behavior, where basic redaction is only performed during common serialization methods like `console.log` and `JSON.stringify`. ::::{warning} Setting `redaction.type` to `off` is not recommended in production environments. :::: ```js const { Client } = require('@elastic/elasticsearch') const client = new Client({ cloud: { id: '' }, auth: { apiKey: 'base64EncodedKey' }, redaction: { type: "off" } }) try { await client.indices.create({ index: 'my_index' }) } catch (err) { console.log(err.meta.meta.request.options.headers.authorization) // the actual header value will be logged } ``` ## Migrate to v8 [_migrate_to_v8] The Node.js client can be configured to emit an HTTP header `Accept: application/vnd.elasticsearch+json; compatible-with=7` which signals to {{es}} that the client is requesting `7.x` version of request and response bodies. This allows for upgrading from 7.x to 8.x version of {{es}} without upgrading everything at once. {{es}} should be upgraded first after the compatibility header is configured and clients should be upgraded second. To enable to setting, configure the environment variable `ELASTIC_CLIENT_APIVERSIONING` to `true`.