Support GitHub-like absolute /path/to/image

[ctjlewis]

In a GitHub README, we reference images like:

![](/assets/images/image.png)

Where the absolute filepath is actually resolved while treating cwd as the root. GitHub resolves paths this way because it's analogous to parking the project on a server, where /assets/... would correctly reference the file in question.

Request: Support GitHub-like absolute paths

It is not sensible to change the default behavior, and Pandoc should probably treat absolute filepaths the way it currently does out of the box. But it would be appropriate to have a --github-absolute-paths flag or something similar to tell Pandoc that /path/to/file actually means ./path/to/file with respect to cwd, i.e. ${pwd}/path/to/file.

Current workaround is to manually replace /assets/... with assets/... (relative), run Pandoc, and then swap back so GitHub can display the images correctly.

Related Issues

• Strange behaviour while accessing images on local file system #8260 (-f markdown+rebase_relative_paths flag)
• Relative images are relative to working directory, not file #3752 (related to GitHub Markdown, but for relative paths)

[ctjlewis]

@tarleb - Tried -f markdown+rebase_relative_paths but was unable to workaround. Thanks for looking at this issue!

[jgm]

OK, right, rebase_relative_paths is only for relative paths, and these are absolute.

I'm not sure what the best solution is. --github-absolute-paths seems a bit clunky; maybe something like --resource-root=$(pwd)?

In the mean time, an easy workaround would be a Lua filter that matches Image elements with absolute paths and removes the leading /.

[tarleb]

function Image (img)
  img.src = pandoc.path.make_relative(img.src, '/')
  return img
end

May require 2.19.2 due to a bug in make_relative in earlier versions.

[dreamos82]

I tried the above solution with pandoc version 2.17.1.1 and apparently it worked.

Btw for completion of information (hoping to be helpful to other pandoc beginners like me) the lua script above, must be saved as it is into a file (i.e. makerelativepaths.lua) and pandoc must be launched with the following parameter:

pandoc ... --lua-filter makerelativepaths.lua