Elasticsearch adapter (@healthzkit/elasticsearch)

The @healthzkit/elasticsearch package provides a HealthAdapter for the official @elastic/elasticsearch client. Each check calls cluster.health() and maps Elasticsearch cluster status to probe status:

Cluster status	Check status
green	ok
yellow	degraded
red	fail

Transport or API errors return fail with the caught error.

Install the adapter package and the peer client:

pnpm add @healthzkit/elasticsearch @elastic/elasticsearch

Peer: @elastic/elasticsearch >= 9.

Package entrypoints

• @healthzkit/elasticsearch — elasticsearchAdapter and option types.
• @healthzkit/elasticsearch/elasticsearch — elasticsearchAdapter only.

Both resolve to the same factory. Use the subpath when you want a dedicated entry for bundlers.

Shared options

BaseElasticsearchOptions:

Option	Description
metadata	Optional (client) => Record<string, unknown> (sync or async) merged into metadata with latencyMs.

Pass either config or an existing client (not both).

elasticsearchAdapter

Each check runs client.cluster.health() and records round-trip latency in metadata.latencyMs, plus clusterStatus, clusterName, and numberOfNodes from the health response.

Config

Pass config as ClientOptions. The adapter lazily imports @elastic/elasticsearch, creates a shared Client, and reuses it across checks. When config is omitted, the default node is http://localhost:9200.

import { createHealthKit } from "healthzkit";
import { elasticsearchAdapter } from "@healthzkit/elasticsearch";

const kit = createHealthKit({
  checks: [
    {
      name: "elasticsearch",
      type: ["readiness"],
      adapter: elasticsearchAdapter({
        config: {
          node: process.env.ELASTICSEARCH_URL ?? "http://localhost:9200",
        },
      }),
    },
  ],
});

Existing client

Pass client as an existing Client. The adapter reuses that instance across checks.

import { Client } from "@elastic/elasticsearch";
import { elasticsearchAdapter } from "@healthzkit/elasticsearch/elasticsearch";

const client = new Client({ node: process.env.ELASTICSEARCH_URL! });

const adapter = elasticsearchAdapter({
  client,
  metadata: async (c) => {
    const info = await c.info();
    return { version: info.version.number };
  },
});

Check metadata

Successful checks include cluster fields alongside any custom metadata hook output:

{
  "status": "ok",
  "metadata": {
    "latencyMs": 18,
    "clusterStatus": "green",
    "clusterName": "docker-cluster",
    "numberOfNodes": 3
  }
}

A yellow cluster yields degraded; a red cluster yields fail while still returning cluster metadata when the API call succeeds.

Wiring into createHealthKit

Treat the factory return value as adapter on a check (same as a hand-written { check() { ... } } object):

adapter: elasticsearchAdapter({ client: myEsClient }),

Combine with schedule on the check if you want cached readiness results instead of calling Elasticsearch on every probe (see Scheduling).