rrq_task_progress_update: Post task update

In richfitz/rrq: Simple Redis Queue

Post task update

Description

Post a task progress update. The progress system in rrq is agnostic about how you are going to render your progress, and so it just a convention - see Details below. Any R object can be sent as a progress value (e.g., a string, a list, etc).

Usage

rrq_task_progress_update(value, error = FALSE)

Arguments

value	An R object with the contents of the update. This will overwrite any previous progress value, and can be retrieved from a rrq_controller with the task_progress method. A value of NULL will appear to clear the status, as NULL will also be returned if no status is found for a task.
error	Logical, indicating if we should throw an error if not running as an rrq task. Set this to FALSE if you want code to work without modification within and outside of an rrq job, or to TRUE if you want to be sure that progress messages have made it to the server.

Details

In order to report on progress, a task may, in it's code, write

rrq::rrq_task_progress_update("task is 90

and this information will be fetchable from rrq_controller using the task_progress method and providing the task_id.

It is also possible to register progress without acquiring a dependency on rrq. If your package/script includes code like:

progress <- function(message) {
  signalCondition(structure(list(message = message),
                            class = c("progress", "condition")))
}

(this function can be called anything - the important bit is the body function body - you must return an object with a message element and the two class attributes progress and condition).

then you can use this in the same way as rrq::rrq_task_progress_update above in your code. When run without using rrq, this function will appear to do nothing.

richfitz/rrq documentation built on March 10, 2024, 12:03 a.m.