Re: ob-plantuml: Proposal to add 'jar-args' customizable variable

[Andy Moreton <andrewjmoreton@gmail.com>]

On Fri 03 Dec 2021, Dejan Josifović wrote:

> Hi all,
>
> I use PlantUML integration in org-mode for years now, but only
> recently I came across some unwanted behavior.
>
> Using PlantUML from jar (org-plantuml-jar-path variable) and latest 
> org-mode, I wanted to render a diagram containing some Unicode 
> characters (such as '⊥' and '∀'), but the end image had some gibberish 
> instead. However,
> trying this from a standalone file using plantuml-mode[1], the end image 
> rendered correctly. Here is some sample code which can reproduce the issue:
>
> #+BEGIN_SRC plantuml :file ./test.png
> A -> B: ∀ characters display correctly is ⊥
> #+END_SRC
>
> Comparing ob-plantuml.el and plantuml-mode.el files I found what is the 
> problem. plantuml-mode has a customizable variable for specifying 
> arguments when using PlantUML from jar (plantuml-jar-args (list 
> "-charset" "UTF-8" ). The charset arguments is what is needed for
> the images to render correctly (I confirmed it by implementing it locally).
>
> I was wondering why such variable doesn't exist in ob-plantuml. I have
> searched the mailing list archives, confirmed bugs and help page and 
> couldn't find anything related.

I use this snippet to set the ob-plantuml.el args to match the
plantuml-mode.el settings:

  (setf (alist-get :java    org-babel-default-header-args:plantuml)
        (mapconcat #'identity plantuml-java-args " ")
        (alist-get :cmdline org-babel-default-header-args:plantuml)
        (mapconcat #'identity plantuml-jar-args " "))

Hope that helps,

    AndyM