support earlyAccessToc frontmatter

lib/frontmatter.js

@@ -62,6 +62,11 @@ export const schema = {
     noEarlyAccessBanner: {
       type: 'boolean',
     },
+    // specify whether an Early Acccess product should have a table of contents
+    // (EA categories and map topics have them by default, but products don't)
+    earlyAccessToc: {
+      type: 'boolean',
+    },
     layout: {
       type: ['string', 'boolean'],
       enum: layoutNames,

middleware/contextualizers/generic-toc.js

@@ -24,8 +24,12 @@ export default async function genericToc(req, res, next) {
     mapTopic: 'flat',
   }
 
+  // Frontmatter can optionally be set on an Early Access product to show hidden child items.
+  // If so, this is a special case where we want to override the flat tocType and use a nested type.
+  const earlyAccessToc = req.context.page.earlyAccessToc
+
   // Find the current TOC type based on the current document type.
-  const currentTocType = tocTypes[req.context.page.documentType]
+  const currentTocType = earlyAccessToc ? 'nested' : tocTypes[req.context.page.documentType]
 
   // Find the part of the site tree that corresponds to the current path.
   const treePage = findPageInSiteTree(
@@ -34,7 +38,7 @@ export default async function genericToc(req, res, next) {
     req.pagePath
   )
 
-  // Only include hidden child items on a TOC page if it's an Early Access category or
+  // By default, only include hidden child items on a TOC page if it's an Early Access category or
   // map topic page, not a product or 'articles' fake cagegory page (e.g., /early-access/github/articles).
   // This is because we don't want entire EA product TOCs to be publicly browseable, but anything at the category
   // or below level is fair game because that content is scoped to specific features.
@@ -43,7 +47,8 @@ export default async function genericToc(req, res, next) {
   const isEarlyAccess = req.context.currentPath.includes('/early-access/')
   const isArticlesCategory = req.context.currentPath.endsWith('/articles')
 
-  req.context.showHiddenTocItems = isCategoryOrMapTopic && isEarlyAccess && !isArticlesCategory
+  req.context.showHiddenTocItems =
+    earlyAccessToc || (isCategoryOrMapTopic && isEarlyAccess && !isArticlesCategory)
 
   // Conditionally run getTocItems() recursively.
   let isRecursive