juancho088 / using-kotlin-serverless-architecture-aws-lambda

Complete code per article for the complete series in medium

Using Kotlin in a Serverless Architecture with AWS Lambda

Complete code per article for the complete series in medium https://medium.com/@juancho088/using-kotlin-in-a-serverless-architecture-with-aws-lambda-part-1-setting-up-the-project-87033790e2f4

First Steps

1. Install nodeJS (download link)
2. Run the command npm install -g serverless
3. Create your project running the command serverless create —-template aws-kotlin-jvm-gradle --path your_service
4. To configure your AWS credentials execute serverless config credentials --provider aws --key EXAMPLE --secret EXAMPLEKEY

Package JSON

1. Create a package.json file with the minimum information so you can install serverless libraries.

{
  "name": "my-blockbuster",
  "version": "1.0.0"
}

Plugins

Serverless to SAM Local

You must have a functional Docker client on the system you plan to use SAM, so install that first if you don’t yet have it!

npm install --save-dev serverless-sam

Add the plugin in the serverless.yml file:

plugins:
  - serverless-sam

Compile your function using Shadow, that will generate a set of files in build/libs/:

gradle build shadowJar

Export and invoke your functions

sls sam export -o template.yml
sam local invoke hello <<< "{}"

Note: You will always need to run this command every single time you want to test your lambda function. Also, by default the function names will start with capital letter.

To invoke custom event.json files you can execute the next command:

$ sam local invoke Hello -e src/main/resources/event.json

Note: Serverless to SAM-local plugin has an error with the memory and timeout values (in general with most od the provider properties). To solve it, change the autogenerated template.yml to include the values that you defined in your serverless.yml file.

MemorySize: 1024
Timeout: 10