Antora integration - Error "Opal is not defined"

[AndreVirtimo]

I have an existing Antora (3.0.1) Project and added this extension by:

npm i asciidoctor-kroki

and add the extension to my playbook:

antora:
  extensions:
    - require: '@antora/lunr-extension'
    - asciidoctor-kroki

When I run antora I get an error:

bpc-docs git:(support/3.5.x) ✗ antora --fetch antora-playbook-local.yml --stacktrace
ReferenceError: Opal is not defined
    at register (/Users/andre/Workspace/bpc-docs/node_modules/asciidoctor-kroki/src/asciidoctor-kroki.js:220:20)
    at /Users/andre/Workspace/bpc-docs/node_modules/@antora/site-generator/lib/generator-context.js:149:37
    at Array.forEach (<anonymous>)
    at GeneratorContext._registerExtensions (/Users/andre/Workspace/bpc-docs/node_modules/@antora/site-generator/lib/generator-context.js:142:18)
    at GeneratorContext._init (/Users/andre/Workspace/bpc-docs/node_modules/@antora/site-generator/lib/generator-context.js:131:10)
    at Function.start (/Users/andre/Workspace/bpc-docs/node_modules/@antora/site-generator/lib/generator-context.js:114:34)
    at generateSite (/Users/andre/Workspace/bpc-docs/node_modules/@antora/site-generator/lib/generate-site.js:10:51)
    at Command.<anonymous> (/usr/local/lib/node_modules/@antora/cli/lib/cli.js:76:20)
    at Command.listener [as _actionHandler] (/usr/local/lib/node_modules/@antora/cli/node_modules/commander/index.js:426:31)
    at Command._parseCommand (/usr/local/lib/node_modules/@antora/cli/node_modules/commander/index.js:1002:14)

[Guillaume Grossetie]

@mojavelinux I believe the reason is that Asciidoctor.js is not yet loaded. I think we need to defer this call right? Is it bad to call LoggerManager.getLogger() every time the block or inline block macro is called?

[Dan Allen]

The issue here is that you are trying to require an Asciidoctor extension as an Antora extension. These are not the same thing. The declaration in the playbook should be:

asciidoc:
  extensions:
  - asciidoctor-kroki

I'm considering updating Antora to detect the misplaced registration and warn about it.

[Guillaume Grossetie]

I completely missed that 🙈
I was mislead by the error message. Thanks for your analysis Dan.

[AndreVirtimo]

Thank you. I missed that because I already had an antora extension in place, so I added this one.

Now it's working:

antora:
  extensions:
    - require: '@antora/lunr-extension'
asciidoc:
  extensions:
    - asciidoctor-kroki