Execute shell commands via Obsidian URI

[Taitava]

I started this discussion based on this discussion: #193.

Quote from @hakonhagland in #193 (reply in thread):

@Taitava I think I found the method, see this line:

this.registerObsidianProtocolHandler("advanced-uri", async (e) => {

The method is defined in the API at line 2418. It looks like it should be possible to use this method like they do in obsidian-advanced-uri plugin? What do you think?

Yes, this can be used. 👍

Quote from @hakonhagland in #193 (comment):

registerObsidianProtocolHandler()

I got two ideas of how this could work. Let's use the obsidian protocol name shell-command as an example. First, by passing a parameter to the shell command like this:

[See page 77 in PDF rererence manual](obsidian://shell-command?commandid=okular?param1=77)

Yea, that's a good example. Small changes to the url:

obsidian://shell-commands?id=XYZ&_param1=77&_another=whatever (Edit 2022-04-15: Actually, keyword id= will be changed to execute=).

Here, _param1 and _another would be custom variable names, and they could be accessed in a shell command like this: echo "My custom variable values are: "{{_param1}}" and "{{_another}}. The names are freelydecideable, but they need to start with an underscore _. Documentation about custom variables comes when the first version of SC that supports them (0.12.0) will be published.

where in this example I would have created an alias called okular for the shell command. Then the shell command could look like this: okular -p {{uri_param:param1}} /home/hakon/pdf_reference.pdf

Aliases are not used as identifiers. They are not unique (you can make two shell commands that use the same alias, there's no restriction for that). So you need to use ids in the url.

And just to reflect my above mention about the custom variables, your shell command would look like this: okular -p {{_param1}} /home/hakon/pdf_reference.pdf

Or, alternatively as the second idea: to avoid repetition of the number 77 in both the link text and in the protocol parameter, allow for defining javascript parser functions (let's say these parser functions can be defined in the shell command settings page). Then the link could look like this instead:

[See page 77 in PDF reference manual](obsidian://shell-command?commandid=okular?link-text-parserid=okular_parser)

here link-text-parserid gives the id of the javascript parser (I created an alias for the parser called okular_parser in this example). The javascript parser is given the link text See page 77 in PDF rererence manual as input argument (it is assumed that this text could somehow be determined from the caret or mouse position when the link is clicked. Is this possible?). The parser is then responsible for returning commandid and the param1 such that we later can call the correct shell command id with the correct parameter (param1=77) as in the first example..

What do you think?

I need to think about it, can't promise anything yet. I could come up with a plan to create some kind of variable for retrieveing a clicked link's label text. My first solution would not be a JavaScript parser for this, I'd pass the link text to the shell command as a whole, and then write the parser in the shell command itself or make it a script file or something.

What comes to being able to execute custom JavaScript via SC in general, it's worth planning and something I want to have at some point, but won't happen soon. I think it will require a public API from this plugin and I'm not ready for that yet. But once I feel comfortable planning it more, I'll write some topic(s) for supporting custom JavaScript.

(it is assumed that this text could somehow be determined from the caret or mouse position when the link is clicked. Is this possible?)

I'm not sure if the caret position goes to the link when clicking. I think a more robust solution would be to hook into the link clicking event.

Current situation

At the moment, Obsidian Advanced URI plugin can be used to execute commands created in SC, using a URL like this:

obsidian://advanced-uri?vault=name&commandid=obsidian-shellcommands%253Ashell-command-99

This, however, does not support passing custom values to the shell command, which can be crucial in some use cases.

[Taitava]

Will be done in version 0.13.0

Implementation issue: #202. If you still have some ideas regarding this feature, discuss them here in Discussions, not in the issue as that's for an implementation summary only.

[Taitava]

Beta test

#228

[Taitava]

Released

@hakonhagland this is now available in 0.13.0.