# Viewing Context
# State diagram
The central piece of viewing is a workflow and state transition. The best way to understand the viewing design is to understand all the states that we have within a viewing and how they transition from one to another.
# Class diagram
# Sequence: Viewing reminder
We need to be able to send a viewing reminder, one day before the viewing happens. We can utilise the AWS Step Function Wait State's TimeStamp feature:
"wait_until" : {
"Type": "Wait",
"Timestamp": "2016-03-14T01:59:00Z",
"Next": "NextState"
}
In a case of rescheduling, we need to be able to stop an execution from
Reminder State Machine
, so:
- Use
Viewing ID
when creating a new execution underReminder State Machine
- Call
stopExecution
withexecutionArn
, which will contain theViewing ID