[AURORA-707] refactor thermos TaskRunner/Process to be more testable

• Type: Task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: Testing, Thermos
• Assignee: Unassigned
• Reporter: Brian Wickman
• Created: 15/Sep/14 18:03
• Updated: 15/Sep/14 18:07

Description

Right now Thermos is mostly tested via an integration test suite. We recently found a bug in Thermos's TaskRunner method collect_updates that should be trivially unit-testable but it's fairly challenging to mock everything in a sane way.

A few things that would be valuable:

• abstract out the checkpoint log – right now TaskRunnerHelper is a mishmash of checkpoint log logic and posix process handling logic.
• remove the task lifecycle logic from TaskRunnerHelper and put somewhere else
• invert the Process/Platform abstraction in order to make it easier to stub out Process (e.g. PosixProcess, ThreadProcess, TestProcess, DockerProcess.)
• move the pid handling logic from TaskRunnerHelper into PosixProcess

Issue Links

• blocks: AURORA-709 Add test coverage to thermos TaskRunner.collect_updates