thom-aws-auth

Description

Lambdas for user authentication with AWS Cognito. Currently learning AWS Lambdas alongside Terraform so using this as a platform for that. This will be used with my web app in the future.

Development

Prerequisites

Installations and setup of the following:

• AWS CLI
• Terraform
• Docker

Setup

npm run setup
npm run build

Run with Docker

I'm using https://localstack.cloud/ for running my lambdas locally and for testing. However, I do not have the pro license required to locally run the AWS services Cognito, Lambda Layers and Gateway V2. I currently have a separate terraform setup for localstack from the aws setup. This is not ideal and so will find a way to change this later.

With the lambda layers needing the pro localstack license, I have come up with a bit of a hack to merge the Layers and Lambas in a single package to deploy to the localstack container. It's not a nice approach but it works for now. A trade off, of course, is I don't get to run integration tests with the Gateway service.

To run with docker, I am using Terraform for spinning up the docker container as well as the localstack setup for the AWS services.

• npm run up - spins up the localstack container with the services for S3 and Lambda
• npm run create:local-lambdas - this is the hack to merge the layers and lambdas into one package (sick face)
• npm run apply:local - apply/deploy S3 and Lambas to the localstack container

Tear down

• npm run destroy:local - destroy the localstack services from the localstack container
• npm run down - tear down the localstack docker container

Deployment

To deploy the AWS services I am using Terraform as per the tf files at location terraform/aws. This process will be moved to a pipeline eventually.

I have added a user to the Cognito user pool and so setting up a secrets tfvars file for the values alongside values for the Cognito env vars.

Change to the terraform directory for aws.

cd terraform/aws

Initialise Terraform and create secrets file

terraform init
touch secrets.tfvars

Add the following to secrets.tfvars file with applicable values:

thom_username = "<username value goes here>"
thom_email = "<email value goes here>"
thom_password = "<password value goes here>"
user_pool_id = "<user pool id goes here>"
client_id = "<client id goes here>"

Validate Terraform

terraform validate

If all is good, plan the changes

terraform plan -out=out.tfplan -var-file=secrets.tfvars

Deploy to AWS

terraform apply "out.tfplan"