ExtendedTasks: how to kill a task?

[mauromiguelm]

Thanks ExtendedTasks implementation, it has a promissing future!

As of shiny 1.8.1.1, the methods available for ExtendedTasks are:

     • ‘ExtendedTask$new()’

     • ‘ExtendedTask$invoke()’

     • ‘ExtendedTask$status()’

     • ‘ExtendedTask$result()’

It would be quite useful to have a ExtendedTask$Kill() method that would kill the respective process associated with the task. Such method would better handle cases of expensive tasks where user decides to change inputs half-way. Such actions would create multiple processes running expensive tasks, which is something we want to avoid.

Concept:

ExtendedTask$kill() # kill all previous task
ExtendedTask$invoke() #start a new task based on new input

[ismirsehregal]

Please check @jcheng5's answer here.

[nirguk]

Based on jcheng5's example solution; I've made a further gist to demonstrate how with R6 subclassing, we can make the $kill() though (I called it $stop_m in my example, for a Mirai backed extendedTask)
link