serverless-positive-chat

An inclusive chat that avoids negative messages and translates the content in the language that you choose, tracking the main topics of a chat room.

Ths application is designed to be completely serverless, using:

• Amazon API Gateway to manage WebSocket communication between the browser and the Lambda function
• AWS Lambda for the custom business logic
• Amazon Comprehend to detect the dominant language, the sentiment of the messages, and its main entities (topics)
• Amazon Translate to translate the messages to the language chosen by each participant of a chat room, or to a language supported by Comprehend for sentiment and entities detection.
• Amazon DynamoDB to store messages, connection information, and the topics discussed in each chat room

You can find a brief description of the architecture here:

https://speakerdeck.com/danilop/serverless-real-time-apps-lets-build-a-positive-chat

A sample deployment is available at:

https://pchat.demo.danilop.net

Pick a username, a chat room, and the language you want to use to receive your messages.

.
├── README.md                   <-- This instructions file
├── positive-chat               <-- Source code for the Lambda function
│   ├── app.js                  <-- Lambda function code
│   └── package.json            <-- Node.js dependencies
├── www                         <-- Source code for the web content
│   ├── index.html              <-- HTML page
│   └── index.js                <-- JavaScript running in the browser
├── deploy.sh                   <-- Deployment script
└── template.yaml               <-- SAM template

Requirements

• AWS CLI already configured with Administrator permission
• AWS SAM CLI to manage serverless deployments

Setup process

Create two S3 buckets, one for the deployment packages and one for hosting the website. Bucket names must be unique, so those in the following example are probably taken:

$ aws s3 mb s3://positive-chat-packages # choose a unique bucket name here
$ aws s3 mb s3://positive-chat-web      # ...

Run the deploy.sh script passing the followng options:

./deploy.sh {PACKAGES_BUCKET} {WWW_BUCKET} {STACK_NAME}

For example, using the buckets you created before, you would use something like:

./deploy.sh positive-chat-packages positive-chat-web positive-chat-prod

The deploy.sh script gets the WebSocket (WSS) URI from the output of the CloudFormation stack to pass it to the web app, uploading a configuration file on S3, so that you don't need to configure it manually.

Using a web browser, go to the S3 bucket you are using for the website, for example (replace the bucket name with the one you created to host the website):

http://positive-chat-web.s3.amazonaws.com/index.html

Then pick a username, a chat room, and the language you want to receive your messages translated to.

Add a CloudFront distribution to have HTTPS access with the domain of your choice. WebSockets are always encrypted (WSS) by the API Gateway.