[FLINK-5716] Make streaming SourceContexts aware of source idleness

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.3.0
• Component/s: API / DataStream
• Assignee: Tzu-Li (Gordon) Tai
• Reporter: Tzu-Li (Gordon) Tai
• Created: 06/Feb/17 09:17
• Updated: 28/Feb/19 10:46
• Resolved: 22/Feb/17 17:25

Description

This task comes after FLINK-5017, which adds the new element StreamStatus to be incorporated with watermark progression logic.

This task tracks the implementation of source idleness awareness and status toggling in {{SourceFunction.SourceContext}}s.

The source contexts should work on an "idle interval", where we determine the containing SourceStreamTask to be idle if no new records / watermarks have been collected in-between 2 continuous checks. (default value is 0. Letting this value be user configurable is tracked by FLINK-5018).

Issue Links

• is blocked by: FLINK-5017 Introduce StreamStatus stream element to allow for temporarily idle streaming sources
• links to: GitHub Pull Request #3347