Using Spring Boot on AWS Lambda

AWS Lambda

AWS Lambda allow us to create small functions such as file transfer data validation most people using JavaScript to handle those things. In this article we will talk about Spring Boot. Is it a good idea to deploy Spring Boot on AWS Lambda?

Let’s Get Started

1. Setup Spring Boot

In order to create Spring Boot project, you can use InteliJ or Spring Initializr

1.1. Project Structure and Dependencies

In this project we going to use Spring Boot version 2.7.6, Spring Cloud version2021.0.5 and Java 11. We need a couple of dependencies for development.

<dependency>  
   <groupId>org.springframework.cloud</groupId>  
   <artifactId>spring-cloud-function-adapter-aws</artifactId>  
</dependency>  

<dependency>  
   <groupId>com.amazonaws</groupId>  
   <artifactId>aws-lambda-java-events</artifactId>  
   <version>3.11.0</version>  
</dependency>  

<dependency>  
   <groupId>com.amazonaws</groupId>  
   <artifactId>aws-lambda-java-core</artifactId>  
   <version>1.2.2</version>  
</dependency>

We need couple more of spring cloud dependencies management

<dependencyManagement>  
   <dependencies>
      <dependency> 
         <groupId>org.springframework.cloud</groupId>  
         <artifactId>spring-cloud-dependencies</artifactId>  
         <version>${spring-cloud.version}</version>  
         <type>pom</type>  
         <scope>import</scope>  
      </dependency>
   </dependencies>
</dependencyManagement>

Final step we need to build our application shade since some dependencies are not require for run on AWS Lambda.

<build>
 <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-shade-plugin</artifactId>
            <version>3.2.4</version>
            <configuration>
                <createDependencyReducedPom>false</createDependencyReducedPom>
            </configuration>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                    <configuration>
                        <artifactSet>
                            <excludes>
                                <exclude>org.apache.tomcat.embed:*</exclude>
                            </excludes>
                        </artifactSet>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

Our project configuration ready to serve request, next we need to create a Java class for handle request. In my case, I require lambda response back as json so, handle request method need to be APIGatewayV2HTTPResponse

public class RequestServiceHandler implements RequestHandler<Map<String, Object>, APIGatewayV2HTTPResponse> {
   @Override
   public APIGatewayV2HTTPResponse handleRequest(Map<String, Object> stringObjectMap, Context context) {
      System.out.println("Lambda function invoke by Java");
      return APIGatewayV2HTTPResponse.builder()
       .withStatusCode(200)
       .withHeaders(Map.of("Content-Type", "application/json"))
       .withBody("{\"message\": \"success\"}")
       .build();
   }
}

Our application is ready to build and deploy into Lambda AWS. Build application by using mvn clean package

1.2. Working with DynamoDB

In development environment we need to add DynamoDB SDK into our project.

<dependency>  
   <groupId>com.amazonaws</groupId>  
   <artifactId>aws-java-sdk-sns</artifactId>  
   <version>1.12.367</version>  
</dependency>

Inside handler class we need to initial AmazonDynamoDBClientBuilder

AmazonDynamoDB amazonDynamoDB = AmazonDynamoDBClientBuilder.standard().withRegion(Regions.US_EAST_1).build();

To save data into DynamoDB we need to construct a Map with a key as String and value as AttributeValue

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Map<String, AttributeValue> map= new HashMap<>();
map.put("id", new AttributeValue(UUID.randomUUID().toString()));
amazonDynamoDB.putItem("your_table_name", map);

1.3. Working with SNS

Similarly, to DynamoDB we also need an SNS SDK

<dependency>  
   <groupId>com.amazonaws</groupId>  
   <artifactId>aws-java-sdk-sns</artifactId>  
   <version>1.12.367</version>  
</dependency>

Back to handler class we need to initial AmazonSNS

AmazonSNS amazonSNS = AmazonSNSClientBuilder.standard().build();

Publish your message SNS Topic by using Topic ARN

amazonSNS.publish("your_topic_arn", "Hello from Lambda!");

2. Deploy Spring Boot to AWS Lambda

Deploy your application to AWS Lambda we need to create an S3 Bucket to store our jar file

Deploy application from S3 Bucket

Enter bucket endpoint

Config your handler class in Runtime Settings

Conclusion

From my own view, by using Java we can achieve the same thing as JavaScript can but, there are some disadvantages:

• Take longer cold start time, in my case an application performs save a couple fields to DynamoDB and publish a message to SNS take around 7s-10s
• Development way harder than JavaScript like 2x because we need a lot of configurations and code editor in Lambda does not support.
• Deployment required to store build file in S3 because Lambda support build file under 10MB, if we upload file larger than 10MB to Lambda browser will crash.
• Required config handler class on Runtime Settings.
• Required minimum memory 512MB