Subscribe a Lambda function to receive notifications from an Amazon SNS topic using an Amazon SDK

/**
 * Subscribe an AWS Lambda endpoint to a topic - demonstrates how to initiate a subscription to an Amazon SNS topic with delivery
 *  to an AWS Lambda function.
 * 
 *  NOTE: You must first configure AWS Lambda to run this example.  
 *         See https://docs.amazonaws.cn/en_us/lambda/latest/dg/with-sns-example.html for more information.
 *
 * <protocol_value> set to "lambda" provides delivery of JSON-encoded message to an AWS Lambda function
 *        (see https://docs.aws.amazon.com/sns/latest/api/API_Subscribe.html for available protocols).
 * <topic_arn_value> can be obtained from run_list_topics executable and includes the "arn:" prefix.
 * <lambda_function_arn> is the ARN of an AWS Lambda function.
 */

int main(int argc, char ** argv)
{
  if (argc != 4)
  {
    std::cout << "Usage: subscribe_lamda <protocol_value=lambda> <topic_arn_value>"
                 " <lambda_function_arn>" << std::endl;
    return 1;
  }

  Aws::SDKOptions options;
  Aws::InitAPI(options);
  {
    Aws::SNS::SNSClient sns;
    Aws::String protocol = argv[1];
    Aws::String topic_arn = argv[2];
    Aws::String endpoint = argv[3];

    Aws::SNS::Model::SubscribeRequest s_req;
    s_req.SetTopicArn(topic_arn);
    s_req.SetProtocol(protocol);
    s_req.SetEndpoint(endpoint);

    auto s_out = sns.Subscribe(s_req);

    if (s_out.IsSuccess())
    {
      std::cout << "Subscribed successfully " << std::endl;
    }
    else
    {
      std::cout << "Error while subscribing " << s_out.GetError().GetMessage()
        << std::endl;
    }
  }

  Aws::ShutdownAPI(options);
  return 0;
}

    public static String subLambda(SnsClient snsClient, String topicArn, String lambdaArn) {

        try {
            SubscribeRequest request = SubscribeRequest.builder()
                .protocol("lambda")
                .endpoint(lambdaArn)
                .returnSubscriptionArn(true)
                .topicArn(topicArn)
                .build();

            SubscribeResponse result = snsClient.subscribe(request);
            return result.subscriptionArn();

        } catch (SnsException e) {
            System.err.println(e.awsErrorDetails().errorMessage());
            System.exit(1);
        }
        return "";
    }

Create the client in a separate module and export it.

import  { SNSClient } from "@aws-sdk/client-sns";
// Set the AWS Region.
const REGION = "REGION"; //e.g. "us-east-1"
// Create SNS service object.
const snsClient = new SNSClient({ region: REGION });
export  { snsClient };

Import the SDK and client modules and call the API.

// Import required AWS SDK clients and commands for Node.js
import {SubscribeCommand } from "@aws-sdk/client-sns";
import {snsClient } from "./libs/snsClient.js";

// Set the parameters
const params = {
  Protocol: "lambda" /* required */,
  TopicArn: "TOPIC_ARN", //TOPIC_ARN
  Endpoint: "LAMBDA_FUNCTION_ARN", //LAMBDA_FUNCTION_ARN
};

const run = async () => {
  try {
    const data = await snsClient.send(new SubscribeCommand(params));
    console.log("Success.",  data);
    return data; // For unit tests.
  } catch (err) {
    console.log("Error", err.stack);
  }
};
run();

suspend fun subLambda(topicArnVal: String?, lambdaArn: String?) {

    val request = SubscribeRequest {
        protocol = "lambda"
        endpoint = lambdaArn
        returnSubscriptionArn = true
        topicArn = topicArnVal
    }

    SnsClient { region = "us-east-1" }.use { snsClient ->
        val result = snsClient.subscribe(request)
        println(" The subscription Arn is ${result.subscriptionArn}")
    }
}