Add closure functionality to publishDir.enabled

[nvnieuwk]

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Usage scenario

In some cases it is useful to be able to specify a closure with the publishDir.enabled attribute. (e.g. I have a meta list in my channel which contains a count of files in one family and I want to only output files that have a count of 1, because the other files will be merged in the next process). Currently the workaround is to use a closure in publishDir.saveAs and not outputting anything when the condition isn't met, but this does still create the folder specified in publishDir.path. Therefore I think it would be a nice addition to add the option of adding closures to the publishDir.enabled attribute.

Example in a config file:

withName: MODULE {
    publishDir = [
        enabled: { meta.count == 1 },
        path: { "${params.outdir}/${meta.id}" }
    ]
}

[bentsherman]

For what it's worth, you might be able to specify that condition in both saveAs and path so that it doesn't always create the folder.

[nvnieuwk]

Yeah you are right, but I think it will be more clear if I could specify it via the publishDir.enabled attribute. But that's a nice workaround for now, thank you!

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[pditommaso]

Closing in favour of #4186

[bentsherman]

Not sure how #4186 will solve this issue, since this one is about allowing enabled to be dynamic where the new issue is about supporting global defaults.

[pditommaso]

You are right. Also, considering there's a workaround, I still believe it is preferable to avoid the proliferation of dynamic config settings

[bentsherman]

Agreed