Quarkus - Amazon Lambda with Resteasy, Undertow, or Vert.x Web 

The quarkus-amazon-lambda-http extension allows you to write microservices with Resteasy (JAX-RS), Undertow (servlet), or Vert.x Web and make these microservices deployable as an Amazon Lambda using Amazon’s API Gateway and Amazon’s SAM framework.

You can deploy your Lambda as a pure Java jar, or you can compile your project to a native image (GraalVM) and deploy that for a smaller memory footprint and startup time.

Prerequisites

To complete this guide, you need:

Getting Started

This guide walks you through generating an example Java project via a maven archetype. Later on it walks through the structure of the project so you can adapt any existing projects you have to use Amazon Lambda.

Installing AWS bits

Installing all the AWS bits is probably the most difficult thing about this guide. Make sure that you follow all the steps for installing AWS SAM CLI.

Creating the Maven Deployment Project

Create the Quarkus AWS Lambda maven project using our Maven Archetype.

mvn archetype:generate \
       -DarchetypeGroupId=io.quarkus \
       -DarchetypeArtifactId=quarkus-amazon-lambda-http-archetype \
       -DarchetypeVersion=1.0.0.CR1

Build and Deploy

Build the project using maven.

mvn clean install

This will compile the code and run the unit tests included within the generated project. Unit testing is all regular local Java and does not require running on Amazon. Quarkus dev-mode is also usable.

If you want to build for native too, make sure you have GraalVM installed correctly and just add a native property to the build

mvn clean install -Dnative

Simulate Amazon Lambda Deployment

The AWS SAM CLI allows you to run your lambda’s locally on your laptop in a simulated Lambda environment. This requires docker to be installed (see their install docs). After you have built your maven project, execute this command

sam local start-api --template sam.jvm.yaml

This will start a docker container that mimic’s Amazon’s Lamba’s deployment environment. Once the environment is started, you can invoke the example lambda in your browser by going to

In the console you’ll see startup messages of the example lambda. This particular deployment starts a JVM and loads your lambda as pure Java.

If you want to deploy a native GraalVM executable of your lambda, use a different yaml template that is provided in your generated project:

sam local start-api --template sam.native.yaml

Deploy to AWS

There are a few steps to get your lambda running on AWS.

Package your deployment.

sam package --template-file sam.jvm.yaml --output-template-file packaged.yaml --s3-bucket <YOUR_S3_BUCKET>

Type the simple name of your S3 bucket you created during. If you’ve built a native executable, replace sam.jvm.yaml with sam.native.yaml.

Deploy your package

sam deploy --template-file packaged.yaml --capabilities CAPABILITY_IAM --stack-name <YOUR_STACK_NAME>

The stack name can be anything you want.

Debugging AWS Deployment Problems

If sam deploy, run the describe-stack-events command to get information about your deployment and what happened.

aws cloudformation describe-stack-events --stack-name <YOUR_STACK_NAME>

One common issue that you may run across is that your S3 bucket has to be in the same region as Amazon Lambda. Look for this error from describe-stack-events output:

Error occurred while GetObject. S3 Error Code: AuthorizationHeaderMalformed. S3 Error Message:
The authorization header is malformed; the region 'us-east-1' is wrong; expecting 'us-east-2'
(Service: AWSLambdaInternal; Status Code: 400; Error Code: InvalidParameterValueException;
Request ID: aefcf978-ad2a-4b53-9ffe-cea3fcd0f868)

The above error is stating that my S3 bucket should be in us-east-2, not us-east-1. To fix this error you’ll need to create an S3 bucket in that region and redo steps 1 and 2 from above.

Another annoying this is that if there is an error in deployment, you also have to completely delete it before trying to deploy again:

aws cloudformation delete-stack --stack-name <YOUR_STACK_NAME>

Execute your REST Lambda on AWS

To get the root URL for your service, type the following command and see the following output:

aws cloudformation describe-stacks --stack-name <YOUR_STACK_NAME>

It should give you something like the following output:

{
    "Stacks": [
        {
            "StackId": "arn:aws:cloudformation:us-east-1:502833056128:stack/QuarkusNativeRestExample2/b35b0200-f685-11e9-aaa0-0e8cd4caae34",
            "DriftInformation": {
                "StackDriftStatus": "NOT_CHECKED"
            },
            "Description": "AWS Serverless Quarkus HTTP - io.demo::rest-example",
            "Tags": [],
            "Outputs": [
                {
                    "Description": "URL for application",
                    "ExportName": "RestExampleNativeApi",
                    "OutputKey": "RestExampleNativeApi",
                    "OutputValue": "https://234234234.execute-api.us-east-1.amazonaws.com/Prod/"
                }
            ],

The OutputValue attribute is the root URL for your lambda. Copy it to your browser and add hello at the end.

Examine the POM

If you want to adapt an existing Resteasy, Undertow, or Vert.x Web project to Amazon Lambda, there’s a couple of things you need to do. Take a look at the generate example project to get an example of what you need to adapt.

  1. Include the quarkus-amazon-lambda-http extension as a pom dependency

  2. Configure Quarkus build an uber-jar

  3. If you are doing a native GraalVM build, Amazon requires you to rename your executable to bootstrap and zip it up. Notice that the pom.xml uses the maven-assemby-plugin to perform this requirement.

Examine sam.yaml

The sam.yaml syntax is beyond the scope of this document. There’s a couple of things to note though that are particular to the quarkus-amazon-lambda-http extension.

Amazon’s API Gateway assumes that HTTP response bodies are text unless you explicitly tell it which media types are binary through configuration. To make things easier, the Quarkus extension forces a binary (base 64) encoding of all HTTP response messages and the sam.yaml file must configure the API Gateway to assume all media types are binary:

  Globals:
    Api:
      EndpointConfiguration: REGIONAL
      BinaryMediaTypes:
        - "*/*"

Another thing to note is that for pure Java lambda deployments, do not change the Lambda handler name.

     Properties:
        Handler: io.quarkus.amazon.lambda.runtime.QuarkusStreamHandler::handleRequest
        Runtime: java8

This particular handler handles all the intricacies of integrating with the Quarkus runtime. So you must use that handler.

Finally, there’s an environment variable that must be set for native GraalVM deployments. If you look at sam.native.yaml you’ll see this:

        Environment:
          Variables:
            DISABLE_SIGNAL_HANDLERS: true

This environment variable resolves some incompatibilites between GraalVM and the Amazon Lambda Custom Runtime environment.