Cleanup orphaned connection using DynamoDB TTL + DynamoDB Streams

[hakobera]

Sometimes client does not correctly send ws.close() event. So we need to clean up.

As of now, AWS API Gateway WebSocket have maximum 2 hours time limit, so we can record connection when we get $onconnect and safely clean it after 2.5 hours later.

• Setup DynamDB TTL feature for connections table
• Add Lambda to clean DynamoDB table and connect it to DynamoDB Streams
  • When record in connections table is deleted, we also need to cleanup rooms table

[aswathrao]

Given the two hour limit, how do you handle the use case in which the session legitimately lasts longer than the stated limit? Do you close the existing connection and open a new open? Thanks.