Feature: Way to trigger rescan on historical builds for a new pattern

[ezyang]

Go to https://circle.pytorch.org/pattern-details.html?pattern_id=59 It has only scanned 3.4% of builds. I want it to scan everything (updating our statuses accordingly). Is there a way to do that?

[kostmo]

Since this can be a long-running task, I think I'll need to implement some logic to prevent multiple simultaneous scans from being started and have a way to view the realtime progress on the web UI

[kostmo]

Fleshing this out a bit more:

• A web UI should be created that can queue the historical scan.
• The UI should specify how far into the past that builds should be rescanned.
• Currently SQS is being used for queuing contemporary build scans. A separate SQS queue should be created for historical scans.
  • In the long term, each time a new pattern is created, a new historical scan could be automatically initiated (with some cooldown delay to allow for the authoring of multiple patterns in a work session; it's more efficient to scan logs for multiple patterns at once).
• A unique identifier for the scan action should be stored in the database and used to display in real time the amount of work done by this scan.