add extension that sets page-project-url and page-project-host attributes on component version

Author: mojavelinux

antora-playbook.yml

@@ -2,6 +2,7 @@ antora:
   extensions:
   - ./ext/asciidoctor-compliance-settings.js
   - ./ext/promote-favicon-to-root.js
+  - ./ext/assign-project-url.js
   - ./ext/page-location.js
 runtime:
   cache_dir: ./.cache/antora

ext/assign-project-url.js

@@ -0,0 +1,25 @@
+'use strict'
+
+module.exports.register = function () {
+  // could switch this to componentsRegistered after upgrading to Antora 3.2
+  this.once('contentClassified', ({ siteAsciiDocConfig, contentCatalog }) => {
+    contentCatalog.getComponents().forEach((component) => {
+      component.versions.forEach((componentVersion) => {
+        const componentVersionId = { component: component.name, version: componentVersion.version }
+        const componentVersionStartPage = contentCatalog.resolvePage('index.adoc', componentVersionId)
+        if (!componentVersionStartPage) return
+        const { startPath, webUrl } = componentVersionStartPage.src.origin
+        if (!(startPath === 'docs' && webUrl)) return
+        if (componentVersion.asciidoc === siteAsciiDocConfig) {
+          componentVersion.asciidoc = Object.assign(
+            {},
+            siteAsciiDocConfig,
+            { attributes: Object.assign({}, siteAsciiDocConfig.attributes) }
+          )
+        }
+        componentVersion.asciidoc.attributes['page-project-url'] = webUrl
+        componentVersion.asciidoc.attributes['page-project-host'] = ~webUrl.indexOf('gitlab') ? 'gitlab' : 'github'
+      })
+    })
+  })
+}