[JAMES-3735] Kill IMAP processing chain

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 3.7.0
• Fix Version/s: 3.8.0
• Component/s: IMAPServer
• Assignee: Unassigned
• Reporter: Benoit Tellier
• Created: 28/Mar/22 04:35
• Updated: 05/May/22 03:09
• Resolved: 05/May/22 03:09

Description

Today we create a processor chain to manage IMAP request: each processor passes the request to the next until the request is managed.

This leads to absurdly, needlessly long call stacks as we easily have 40+ processors.

• This have a performance impact as feeling thread stacks do not come for free
• Exceptions are hard to read (longer stacktraces)
• Reading flame graphs is also harder!

We should in my opinion just use a map to directly get the processor for a given request, simply using the request class as a key.