[FLINK-7169] Support AFTER MATCH SKIP function in CEP library API

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.4.0
• Component/s: Library / CEP
• Assignee: Yueting Chen
• Reporter: Yueting Chen
• Created: 13/Jul/17 05:34
• Updated: 01/Oct/19 15:39
• Resolved: 05/Sep/17 03:29

Description

In order to support Oracle's MATCH_RECOGNIZE on top of the CEP library, we need to support AFTER MATCH SKIP function in CEP API.

There're four options in AFTER MATCH SKIP, listed as follows:
1. AFTER MATCH SKIP TO NEXT ROW: resume pattern matching at the row after the first row of the current match.
2. AFTER MATCH SKIP PAST LAST ROW: resume pattern matching at the next row after the last row of the current match.
3. AFTER MATCH SKIP TO FIST RPV: resume pattern matching at the first row that is mapped to the row pattern variable RPV.
4. AFTER MATCH SKIP TO LAST RPV: resume pattern matching at the last row that is mapped to the row pattern variable RPV.

I think we can introduce a new function to `CEP` class, which takes a new parameter as AfterMatchSKipStrategy.

The new API may looks like this

public static <T> PatternStream<T> pattern(DataStream<T> input, Pattern<T, ?> pattern, AfterMatchSkipStrategy afterMatchSkipStrategy) 

We can also make `SKIP TO NEXT ROW` as the default option, because that's what CEP library behaves currently.

Issue Links

• relates to: FLINK-7172 Add a event logical id field to ValueTimeWrapper
• links to: GitHub Pull Request #4331