with-sns-create-package.md

Sample function code

Sample code is available for the following languages.

Topics

• Node.js 12.x
• Java 11
• Go
• Python 3

Node.js 12.x

The following example processes messages from Amazon SNS, and logs their contents.

Example index.js

console.log('Loading function');

exports.handler = function(event, context, callback) {
// console.log('Received event:', JSON.stringify(event, null, 4));

    var message = event.Records[0].Sns.Message;
    console.log('Message received from SNS:', message);
    callback(null, "Success");
};

Zip up the sample code to create a deployment package. For instructions, see Deploy Node.js Lambda functions with .zip file archives.

Java 11

The following example processes messages from Amazon SNS, and logs their contents.

Example LogEvent.java

package example;

import java.text.SimpleDateFormat;
import java.util.Calendar;

import com.amazonaws.services.lambda.runtime.RequestHandler;
import com.amazonaws.services.lambda.runtime.Context;
import com.amazonaws.services.lambda.runtime.events.SNSEvent;

public class LogEvent implements RequestHandler<SNSEvent, Object> {
    public Object handleRequest(SNSEvent request, Context context){
    String timeStamp = new SimpleDateFormat("yyyy-MM-dd_HH:mm:ss").format(Calendar.getInstance().getTime());
    context.getLogger().log("Invocation started: " + timeStamp);
    context.getLogger().log(request.getRecords().get(0).getSNS().getMessage());

    timeStamp = new SimpleDateFormat("yyyy-MM-dd_HH:mm:ss").format(Calendar.getInstance().getTime());
    context.getLogger().log("Invocation completed: " + timeStamp);
           return null;
     }
}

Dependencies

• aws-lambda-java-core
• aws-lambda-java-events

Build the code with the Lambda library dependencies to create a deployment package. For instructions, see Deploy Java Lambda functions with .zip or JAR file archives.

Go

The following example processes messages from Amazon SNS, and logs their contents.

Example lambda_handler.go

package main

import (
    "context"
    "fmt"
    "github.com/aws/aws-lambda-go/lambda"
    "github.com/aws/aws-lambda-go/events"
)

func handler(ctx context.Context, snsEvent events.SNSEvent) {
    for _, record := range snsEvent.Records {
        snsRecord := record.SNS
        fmt.Printf("[%s %s] Message = %s \n", record.EventSource, snsRecord.Timestamp, snsRecord.Message)
    }
}

func main() {
    lambda.Start(handler)
}

Build the executable with go build and create a deployment package. For instructions, see Deploy Go Lambda functions with .zip file archives.

Python 3

The following example processes messages from Amazon SNS, and logs their contents.

Example lambda_handler.py

from __future__ import print_function
import json
print('Loading function')

def lambda_handler(event, context):
    #print("Received event: " + json.dumps(event, indent=2))
    message = event['Records'][0]['Sns']['Message']
    print("From SNS: " + message)
    return message

Zip up the sample code to create a deployment package. For instructions, see Deploy Python Lambda functions with .zip file archives.