Kotlin Gradle Serverless Template

This is a boilerplate template for serverless using AWS, Kotlin, and Gradle.

I also have a Serverless template using Spring Cloud Function, aws-kotlin-jvm-spring.

Requirements

• Serverless 1.24 or higher
• Gradle 4 and JDK8

Usage

# Create template
serverless create --template-url https://github.com/jswift/aws-kotlin-jvm-gradle \
    --path helloworld --name hello && cd helloworld

# Build and deploy the hello world function
gradle deploy

Handlers

When developing Handlers they should be updated to use the correct event, not the default event as displayed in the template Handler. For example, a function that responds to a HTTP event would look like:

class Handler: RequestHandler<APIGatewayProxyRequestEvent, ApiGatewayResponse> {
    override fun handleRequest(event: APIGatewayProxyRequestEvent, context: Context): ApiGatewayResponse {
        // Do stuff
    }
}

Response

Response objects extend the Response class and are converted to JSON. The simplest option is to create a data class, as demonstrated in HelloResponse.

AWS Java SDK

If you need to use the AWS Java SDK in your functions, you can use the Bill-of-Materials (BOM) provided in the gradle file. When adding a library, such as S3, you just add compile 'com.amazonaws:aws-java-sdk-s3' to the dependecies and it will ensure all your libraries are at the correct version.