[help] How to view output (stdout) of processes running with controller = crew_controller_local()?

[venpopov]

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Description

If I run a pipeline with no parallel processing, the output of functions is printed to the console. For example, running a brms model prints progress information about completed iterations. However, when running models in parallel locally with

tar_options_set(controller = crew_controller_local(workers = 2))

there is no output. I tried looking into the reference pages for crew and callr, but I cannot figure out how to redirect the output when crew is used from within targets. Any suggestions?

[venpopov]

Ah, figured it out. For anyone else who might search for this:

In argument local_log_directory to crew_controller_local() you can specify where to output stdout and stderror of crew workers. E.g.:

# Set target options:
tar_option_set(
  controller = crew_controller_local(workers = 2, local_log_directory = "output/logs")
)