AWSConnection.js

const AWS = require('aws-sdk');
const { Connection } = require('@elastic/elasticsearch');

class AWSConnection extends Connection {
    async request(params, callback) {
        try {
            const creds = await this._getAWSCredentials();
            const req = this._createRequest(params);

            const { request: signedRequest } = this._signRequest(req, creds);
            super.request(signedRequest, callback);
        } catch (error) {
            throw error;
        }
    }

    _createRequest(params) {
        const endpoint = new AWS.Endpoint(this.url.href);
        let req = new AWS.HttpRequest(endpoint);

        Object.assign(req, params);
        req.region = AWS.config.region;

        if (!req.headers) {
            req.headers = {};
        }

        let body = params.body;

        if (body) {
            let contentLength = Buffer.isBuffer(body)
                ? body.length
                : Buffer.byteLength(body);
            req.headers['Content-Length'] = contentLength;
            req.body = body;
        }
        req.headers['Host'] = endpoint.host;

        return req;
    }

    _getAWSCredentials() {
        return new Promise((resolve, reject) => {
            AWS.config.getCredentials((err, creds) => {
                if (err) {
                    if (err && err.message) {
                        err.message = `AWS Credentials error: ${e.message}`;
                    }
                    reject(err);
                }
                resolve(creds);
            });
        });
    }

    _signRequest(request, creds) {
        const signer = new AWS.Signers.V4(request, 'es');
        signer.addAuthorization(creds, new Date());
        return signer;
    }
}

module.exports = { AWSConnection };