Generate a signed URL using AWS Signature Version 4 (SigV4) for ElastiCache IAM authentication.

sign-elasticache-url.ts

import * as aws4 from 'aws4';

type Credentials = {
  accessKeyId: string,
  secretAccessKey: string,
  sessionToken: string
};
/**
 * Generate a signed request to the AWS ElastiCache service for IAM authentication
 */
const getToken = (
  credentials: Credentials,
  userId: string,
  cacheName: string,
  region: string = 'eu-west-1',
  isServerless: boolean = true,
  expiry: number = 900  // seconds
): string => {
  const signed = aws4.sign(
            {
                service: 'elasticache',
                region,
                method: 'GET',
                host: cacheName,
                setHost: true,
                path: `/?Action=connect&User=${encodeURI(userId)}${
                    isServerless ? '&ResourceType=ServerlessCache' : ''
                }&X-Amz-Expires=${expiry}`,
                protocol: 'http',
                signQuery: true,
                body: ''
            },
            {
                accessKeyId: credentials.accessKeyId,
                secretAccessKey: credentials.secretAccessKey,
                sessionToken: credentials.sessionToken
            }
        );
        return `${signed.host}${signed.path}`.replace('http://', '');
};

// usage:
// getToken();