# cql-hl-demo
This project contains source code to create a serverless CDS Hook that interacts with Amazon Healthlake and runs a CQL query to detect contagious disease symptoms. Solution design is shown in the following diagram:

![CDS Hook Solution Design](/assets/img/solution-design.png "CDS Hook")

## Deploy the  application

The AWS SAM CLI is an extension of the AWS CLI that adds functionality for building and testing Lambda applications. It uses Docker to run your functions in an Amazon Linux environment that matches Lambda. It can also emulate your application's build environment and API.

To use the AWS SAM CLI, you need the following tools:

* AWS SAM CLI - [Install the AWS SAM CLI](https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/serverless-sam-cli-install.html).
* Node.js - [Install Node.js 18](https://nodejs.org/en/), including the npm package management tool.
* Docker - [Install Docker community edition](https://hub.docker.com/search/?type=edition&offering=community).

To build and deploy your application for the first time, run the following in your shell:

```bash
sam build
sam deploy --guided
```

The first command will build the source of your application. The second command will package and deploy your application to AWS, with a series of prompts:

* **Stack Name**: The name of the stack to deploy to CloudFormation. This should be unique to your account and region, and a good starting point would be something matching your project name.
* **AWS Region**: The AWS region you want to deploy your app to.
* **Confirm changes before deploy**: If set to yes, any change sets will be shown to you before execution for manual review. If set to no, the AWS SAM CLI will automatically deploy application changes.
* **Allow SAM CLI IAM role creation**: Many AWS SAM templates, including this example, create AWS IAM roles required for the AWS Lambda function(s) included to access AWS services. By default, these are scoped down to minimum required permissions. To deploy an AWS CloudFormation stack which creates or modifies IAM roles, the `CAPABILITY_IAM` value for `capabilities` must be provided. If permission isn't provided through this prompt, to deploy this example you must explicitly pass `--capabilities CAPABILITY_IAM` to the `sam deploy` command.
* **Save arguments to samconfig.toml**: If set to yes, your choices will be saved to a configuration file inside the project, so that in the future you can just re-run `sam deploy` without parameters to deploy changes to your application.

The API Gateway endpoint API will be displayed in the outputs when the deployment is complete.

## Use the AWS SAM CLI to build and test locally

Build your application by using the `sam build` command.

```bash
my-application$ sam build
```


Deploy the  application.

```bash
my-application$ sam deploy
```

Open the [**Applications**](https://console.aws.amazon.com/lambda/home#/applications) page of the Lambda console, and choose your application. When the deployment completes, view the application resources on the **Overview** tab to see the new resource. Then, choose the function to see the updated configuration that specifies the dead-letter queue.


## Cleanup

To delete the sample application that you created, use the AWS CLI. Assuming you used your project name for the stack name, you can run the following:

```bash
aws cloudformation delete-stack --stack-name cql-hl-demo
```

## Resources

For an introduction to the AWS SAM specification, the AWS SAM CLI, and serverless application concepts, see the [AWS SAM Developer Guide](https://docs.aws.amazon.com/serverless-application-model/latest/developerguide/what-is-sam.html).

Next, you can use the AWS Serverless Application Repository to deploy ready-to-use apps that go beyond Hello World samples and learn how authors developed their applications. For more information, see the [AWS Serverless Application Repository main page](https://aws.amazon.com/serverless/serverlessrepo/) and the [AWS Serverless Application Repository Developer Guide](https://docs.aws.amazon.com/serverlessrepo/latest/devguide/what-is-serverlessrepo.html).