Auth0 Micronaut template

Live

App is deployed to AWS Lambda:

	JAR with StreamLambdaHandler	Graal VM native binary with custom runtime
Branch	master	aws-lambda-graalvm
URL	https://te60oj36jd.execute-api.eu-west-1.amazonaws.com/Prod/	https://995oz2jt04.execute-api.eu-west-1.amazonaws.com/Prod/

Client application using this API:

Website URL	Github repository
https://ivarprudnikov.github.io/react-auth0-template/	https://github.com/ivarprudnikov/react-auth0-template

About

Example should serve as a template when necessary to write a small service which uses JWT tokens signed by Auth0 server.

Blog post explaining implementation - ivarprudnikov.com/micronaut-kotlin-jwt-secured-api-aws-lambda

JWT config (by using JWKS) is visible in application.yml. Controller endpoint then uses @Secured annotation.

API endpoints

• / - returns status UP in plain text
• /me - returns user io.micronaut.security.authentication.Authentication in JSON response

Development

Running locally

Start Micronaut server

./gradlew run

Then to check status

curl http://localhost:8080
UP%

Running with SAM

This requires Docker to be running locally and sam CLI installed. https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/sam-cli-command-reference-sam-local-start-api.html

sam local start-api --template template.yaml --port 8080

....

Mounting ExampleFunction at http://127.0.0.1:8080/ [DELETE, GET, HEAD, OPTIONS, PATCH, POST, PUT]
Mounting ExampleFunction at http://127.0.0.1:8080/{proxy+} [DELETE, GET, HEAD, OPTIONS, PATCH, POST, PUT]
You can now browse to the above endpoints to invoke your functions. You do not need to restart/reload SAM CLI while working on your functions, changes will be reflected instantly/automatically. You only need to restart SAM CLI if you update your AWS SAM template
2020-03-02 22:16:20  * Running on http://127.0.0.1:8080/ (Press CTRL+C to quit)

Invoking function with events

Instead of running the application and then trying to invoke API in the browser you could just invoke Lambda function with pre-built events:

sam local invoke --template template.yaml --event aws-test-events/options-me.json --skip-pull-image

Packaging and deployment

Utilizing AWS Lambda to make sure I'm not paying for idle time.

Example micronaut implementations:

• https://github.com/micronaut-projects/micronaut-aws/tree/master/examples/api-gateway-example
• https://github.com/micronaut-guides/micronaut-function-aws-lambda Example micronaut implementations using Graal VM (native binaries):
• https://github.com/awslabs/aws-serverless-java-container/tree/master/samples/micronaut/pet-store
• https://github.com/micronaut-guides/micronaut-creating-first-graal-app

Steps

1. Build jar

   ./gradlew clean build --info

2. Create S3 bucket where application version is going to be uploaded before deployed to Cloudformation:

   aws s3 mb s3://BUCKET_NAME

3. Package Lambda (uploads to S3):

   sam package \
       --output-template-file packaged.yaml \
       --s3-bucket BUCKET_NAME

4. Create Cloudformation Stack and deploy your SAM resources.

   sam deploy \
       --template-file packaged.yaml \
       --stack-name STACK_NAME \
       --capabilities CAPABILITY_IAM

5. After deployment is complete you can run the following command to retrieve the API Gateway Endpoint URL:

   aws cloudformation describe-stacks \
       --stack-name STACK_NAME \
       --query 'Stacks[].Outputs[?OutputKey==`ApiUrl`]' \
       --output table

Simpler way

Below sam validate requires AWS Credentials to be set up.

sam validate && LAMBDA_APP_NAME=auth0-micronaut-template bash build-deploy.sh

Cloudformation cleanup

In order to delete our Serverless Application recently deployed you can use the following AWS CLI Command:

aws cloudformation delete-stack --stack-name STACK_NAME