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

To complete this guide, you need:

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 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.

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

Build the project using maven.

This will compile the code and run the unit tests included within the generated project. Unit testing is the same as any other Java project and does not require running on Amazon. Quarkus dev-mode is also available with this extension.

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

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

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

http://127.0.0.1:3000/hello

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

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

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

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

It should give you something like the following output:

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

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.

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:

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

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:

This environment variable resolves some incompatibilities between Quarkus and the Amazon Lambda Custom Runtime environment.

If you are building native images, and want to use AWS X-Ray Tracing with your lambda you will need to include quarkus-amazon-lambda-xray as a dependency in your pom. The AWS X-Ray library is not fully compatible with GraalVM so we had to do some integration work to make this work.