[help] tar_cue_skip() even if target never built

[nousyeli]

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Description

Hello,
I'm wondering if there is an option to have similar functionality as tar_target( ..., cue = tar_cue_skip(TRUE) but skip even if the target has never been built.

For more context, incase someone has other ideas:
I'm in a situation where I need to handover a pipeline, I'd like to have a version that connects to a database and API. And another version that runs out of the box, replacing the API reponse and database queries with parquet files that I can include in the handover. Then hopefully I can easily change a variable that would switch between the two versions. This is because the API calls and database queries take a lot of time.

Thank you, I appreciate your help!
Cheers,
E

[wlandau]

I'm wondering if there is an option to have similar functionality as tar_target( ..., cue = tar_cue_skip(TRUE) but skip even if the target has never been built.

This is not feasible in targets.

For more context, incase someone has other ideas:
I'm in a situation where I need to handover a pipeline, I'd like to have a version that connects to a database and API. And another version that runs out of the box, replacing the API reponse and database queries with parquet files that I can include in the handover. Then hopefully I can easily change a variable that would switch between the two versions. This is because the API calls and database queries take a lot of time.

You could write _targets.R in such a way that it responds to a set of parameters or environment variables that you control. It's very flexible because you can control what is inside _targets.R. One possible sketch:

# _targets.R file
do_task3 <- TRUE

library(targets)

constant_part <- list(
  tar_target(task1, do_task1()),
  tar_target(task2, do_task2())
)

if (do_task3) {
  variable_part <- tar_target(task3, do_task3())
} else {
  variable_part <- NULL
}

list(constant_part, variable_part)