Feature request: Render hierarchical tags (e.g. "Parent|Child") as nested albums

[seanakabry]

Could the functionality of the %keywords option for the --albums-from flag be expanded to handle nested IPTC keywords?

The section on keywords in the relevant IPTC specification doesn't say anything about hierarchies, but Adobe Bridge's default delimiter is a pipe, which is also recognised by LIghtroom Classic.

If an image were assigned the keywords tag|subtag and tag|subtag|subsubtag, it would appear in the albums /tag/subtag and /tag/subtag/subsubtag, but not /tag.

---

In the meantime, can this behaviour be achieved using a custom mapping function (--albums-from "file://...)?

I got as far as this function, which is supposed to recognise keywords containing one pipe: (apologies for my ignorance of JS)

const eventRegex = /(.+)\|(.+)/
const tags = new Array();
module.exports = file => {
  file.meta.keywords.forEach(function(tag) {
    const match = eventRegex.exec(tag)
    if (match) {
      const parent = match[1]
      const child = match[2]
      tags.push([`Tags/${parent}/${child}`])
    } else {
      tags.push([`Tags/${tag}`])
    }
  })
  return tags
}

but the gallery will not compile:

Unexpected error The "path" argument must be of type string. Received an instance of Array

If the array tags is returned as a comma-delimited string, the gallery compiles, but the albums are recursively nested like so:

Tags/ParentA/ChildA/Tags/ParentB/ChildB

Thank you for the excellent software.

[rprieto]

Hi, I like this idea very much. Thanks for raising it.
Would it make sense to also recognise keyword1/keyword2 as a hierarchy (slash in addition to pipe)?
Edit: it's undocumented, but I realise now it might already behave like this

I'll try to troubleshoot your custom mapper, and as a second steps see if we can support this by default in %keywords.
Stay tuned!

[seanakabry]

Thank you, Romain. I just switched to using / as a delimiter, and confirm that this feature is already implemented as you suggest. (So please feel free to ignore the mapper.)

Perhaps the option to use other delimiters would be a welcome nicety (for users with extensive, already-tagged collections), but I don't think Thumbsup is wrong to prefer the forward slash as the default; it certainly seems most intuitive to me.

Adobe Bridge defaults to | but lets users choose from /, \, and :. Lightroom Classic is probably not a relevant consideration after all, because it doesn't preserve keyword hierarchies on export (just exports them flat).

[rprieto]

Hi, sorry for the delay. Do you think it's reasonable if:

• you could pass additional delimiters via a flag like --album-path-delimiters
• thumbsup simply does a string replace of these characters to a /

The awkward edge case is if you have a slash in your tags,e.g. Holidays|Japan/Australia 2021.

I'm guessing it should keep Japan/Australia 2021 as a single album.

[seanakabry]

Please don't apologise!

I think the new flag would be best, with / as the default. Though | and \ are rare, it's not hard to imagine problematic edge cases with a string replacement of :, such as 2022/Conference Title: Conference Subtitle.

If Thumbsup interprets --album-path-delimiters | to mean that only pipes are delimiters (not the default plus pipes), the flag also side-steps the edge case you gave (which I think is what you were saying). This seems more elegant than introducing an escape character.

In any case, I think the lowest hanging fruit is probably to mention in the documentation that Thumbsup is already capable of interpreting hierarchical tags.

[rprieto]

In fact it's trickier than planned. Initially I thought we could change the whole hierarchy system to understand a different character.

However, the code is based on file system helpers and specifically expects /. Moreover, if we changed it, the very basic use case of creating albums per file path wouldn't work anymore.

So I think the logic will have to be specific to IPTC keywords:

if --keyword-path-separator is specified:
  remove all / characters from keywords
  replace the specified character with /

So a file with the keyword Holidays|Japan/Australia 2021 would end up in the album Holidays > Japan Australia 2021.

That would be easy to implement and test, and have minimal side effects!

[rprieto]

And agreed on the low hanging fruit! I'll update the documentation later, unless you want to submit a pull request to https://github.com/thumbsup/docs