Re: [TASK] Allow customizeable ditaa executable in ob-ditaa.el

[Max Nikulin]

On 10/11/2023 10:19, Leo Butler wrote:
> On Thu, Nov 09 2023, Max Nikulin wrote:
>
> > diff --git a/lisp/ob-ditaa.el b/lisp/ob-ditaa.el
[...]
> > should allow to set :java to
> >
> >      flatpak-spawn --host toolbox run /usr/bin/ditaa
> >
> > without abusing of org-ditaa-jar-path. Untested.
>
> Doesn't this abuse the `java' header argument, which is intended to pass
> arguments to the java runtime?

or `org-babel-ditaa-java-cmd'. My point is that requirement of non-empty 
`org-ditaa-jar-path' confused Florin to the degree when workarounds 
looked impossible. Notice that setting

    org-ditaa-jar-path "/usr/bin/ditaa"

still requires spreading of "flatpack-spawn ..." over 
`org-babel-ditaa-java-cmd', :java, and `org-ditaa-jar-option'. 
fortunately some of these options may be sent empty and other will not 
quote spaces, etc. Whole "flatpack-spawn ... ditaa" command can not be 
put to `org-ditaa-jar-path'

> I think that it would be best to implement the change to mirror that
> done in ob-plantuml, as Ihor suggested earlier.

Agree. I appreciate consistency in treatment of similar cases.

I am not sure in the following idea. Perhaps a concept of "launcher" (or 
"runner") may be introduced. Launchers may be stacked. So for a jar file 
launcher is "java @:java -jar" that may be combined with "toolbox run" 
and "flatpak-spawn --host" launchers.

> My reading of the documentation and ob-plantuml.el is that it is not
> possible to use the `java' header argument in the way you propose for
> ob-ditaa.el.

Since nobody has proposed a patch for ob-ditaa, I decided that making a 
workaround easier is an improvement.

     #+property: header-args:ditaa :java ...

would not affect ob-plantuml.

P.S. I am unsure what is proper balance between flexibility/convenience 
and security. A file downloaded from net should not be able to change 
executables and their options without consent from the user. 
Unfortunately attempts to suppress at least shell expansion will lead to 
more verbose configuration.