ChatNow is a chat service based on AWS and NextJS.

ChatNow uses the NextJS React Framework and is hosted using AWS Amplify.

ChatNow uses the following AWS Services:

• Amazon Cognito for authentication.
• AWS AppSync for mapping databases and real-time notifications.
• AWS Lambda for creating initialization triggers for adding users to the database with Amazon Cognito, providing a list of active and inactive users.
• Amazon DynamoDB for creating a multi-table database for users and messages.
• Amazon S3 for storing user uploads and front-end web resources.

• Node.js (Windows/Mac/Linux): Node.js is an asynchronous event-driven JavaScript runtime designed to build scalable network applications. To install Node.js, visit the Node.js download page and select the version relevant to your machine.
• VS Code (Windows/Mac/Linux): If you do not have a preffered editor, VS Code is a useful editor for this project. To install VS Code, visit the Visual Studio Code download page.

• Once all required software is installed, navigate to the working directory through your terminal and enter npm run dev.
• Now, visit localhost:3000/.
• If you run into the error Error: error:0308010C:digital envelope routines::unsupported, you will either need to downgrade your Node.js to version 16 or enable the legacy OpenSSL provider, then retry npm run dev:

On Unix-like (Linux, macOS, Git bash, etc.):

export NODE_OPTIONS=--openssl-legacy-provider

On Windows command prompt:

set NODE_OPTIONS=--openssl-legacy-provider

On PowerShell:

$env:NODE_OPTIONS = "--openssl-legacy-provider"

The lib/authStack.ts file creates the following services

• Cognito user pool
• Cognito user pool group (if specified)
• Cognito identity pool

🗒️ The identity pool helps in providing IAM permission access to both authenticated and unauthenticated users as well as AWS services such as Amazon S3.

The lib/functions directory contains a postConfirmationTrigger folder. The Lambda function in this folder adds a user to DynamoDB after a user signs up through our Cognito service.

The lib/fileStorage.ts file creates an Amazon S3 bucket and comes configured with managed polices that are in line with what the Amplify Storage library uses as acceptable defaults.

Thelib/apiStack.ts file creates an AWS AppSync API that is based on a Todo application.

In addition, this package makes use of the @aws-cdk/aws-appsync-alpha npm package for easily creating the request and response mapping templates.

The lib/databaseStack.ts file creates a single DynamoDB table that is used as a datasource for the AWS AppSync API above.

• npm run dev compile to js and host on local server
• npm run watch watch for changes and compile
• cdk deploy deploy this stack to your default AWS account/region
• cdk diff compare deployed stack with current state
• cdk synth emits the synthesized CloudFormation template

This library is licensed under the MIT-0 License. For more information, see the LICENSE file.