AWS Websocket notes

WSCAT – utility is a convenient tool for testing a WebSocket API

Tutorial: Building a serverless chat app with a WebSocket API, Lambda and DynamoDB

Video implementation

Backends for front end pattern

AWS Document
The backend can send callback messages to connected clients.

Sending messages back to connected clients

Use @Connect command in backend

WebSocket APIs for API Gateway charge for the messages you send and receive. You can send and receive messages up to 128 KB in size. Messages are metered in 32-KB increments, so a 33-KB message is charged as two messages. If larger message is received, connection will close with code 1009.

In addition to paying for the messages you send and receive, you are also charged for the total number of connection minutes.