[FLINK-4992] Expose String parameter for timers in Timely functions and TimerService

• Type: Improvement
• Status: Reopened
• Priority: Not a Priority
• Resolution: Unresolved
• Affects Version/s: 1.2.0
• Component/s: API / DataStream
• Assignee: Unassigned
• Reporter: Gyula Fora
• Created: 02/Nov/16 08:47
• Updated: 29/Jul/21 07:36

Description

Currently it is very hard to register and execute multiple different types timers from the same user function because timers don't carry any metadata.

We propose to extend the timer registration and onTimer logic by attaching a String argument so users of these features can implement functionality that depends on this addtitional metadata.

The proposed new methods:

In the TimerService:
void registerProcessingTimeTimer(long time, String label);
void registerEventTimeTimer(long time, String label);

In the TimelyFunctions:
void onTimer(long timestamp, String label, TimeDomain timeDomain, TimerService timerService...);

This extended functionality can be mapped to a String namespace for the internal timer service. I suggest we don't use the term "namespace" here because it just complicates things for the users, I think "label" or "id" or "name" is much simpler to understand.

Issue Links

• is depended upon by: FLINK-5026 Rename TimelyFlatMap to Process