Is it possible to modify the resource path from lua?

[CodeSandwich]

I need to dynamically load markdown files referencing resources relatively. E.g. docs/03/doc.md references docs/03/MEDIA/image.png as ![](MEDIA/image.png). If I run pandoc --resource-path=docs/03 docs/03/doc.md ..., they are found just fine, but if I load the markdown file dynamically, with pandoc.read there doesn't seem to be any way to perform pandoc.mediabag.fetch that would include docs/03 as the search path unless I declare this path with --resource-path when starting pandoc. There's the PANDOC_STATE.resource_path list, but it's read-only, modifying it has no effect.

[tarleb]

Currently it's not possible. I have a WIP branche in which I tried to create a solution for that, but that needs more work.

[CodeSandwich]

Awesome, I hope that you'll succeed! Since it's a missing feature, I've opened an issue: #10859.

[rnwst]

@CodeSandwich -- as a workaround, you can use a filter to change all image paths before rendering so that they are relative to the working directory rather than the document in which they appear:

-- read Markdown file
local mdpath = 'subdir/doc.md'
local doc = pandoc.read(select(2, pandoc.mediabag.fetch(mdpath)))

-- run filter to make image paths relative to working dir
doc = doc:walk {
   ---@type fun(img: Image): Image
   Image = function(img)
      img.src = pandoc.path.join { pandoc.path.directory(mdpath), img.src }
      return img
   end,
}

-- render doc
print(pandoc.write(doc, 'html'))

You can find a full example here: https://github.com/rnwst/pandoc-discussions/tree/master/10670