add tags to the search metadata

make-search-index.js

@@ -3,8 +3,8 @@
  * make-search-index.js
  *
  * This converts a "search data" file produced by the haskell site builder into
- * a lunr.js index and saves it in JSON. Metadata for search (currently titles)
- * are stored separately in an extra file.
+ * a lunr.js index and saves it in JSON. Metadata for rendering search output
+ * (currently titles and tags) are stored separately in an extra file.
  *
  * Installing dependencies:
  * yarnpkg add lunr
@@ -35,5 +35,5 @@ var idx = lunr(function () {
 
 fs.writeFileSync(process.argv[3], JSON.stringify(idx), {encoding: 'utf8'})
 fs.writeFileSync(process.argv[4], JSON.stringify(
-    Object.fromEntries(documents.map(x => [x.link, x.title]))
+    Object.fromEntries(documents.map(x => [x.link, {"title": x.title, "tags": x.tags}]))
   ), {encoding: 'utf8'})

site.hs

@@ -348,13 +348,17 @@ renderTags = use (htags . to M.keys) >>= traverse_ renderTag
 -- | Transform one mounted PageInfo to the base search data
 mkSearchData :: FilePath -> PageInfo -> Site Y.Value
 mkSearchData mount pi = do
+  link <- rootUrl mount
   text <- io . runIOorExplode $ writePlain plainWriteOpts (pi ^. pageDoc)
   let title = pi ^? pageMeta . key "title" . _String
-  link <- rootUrl mount
+  let tags =
+        pi ^.. pageMeta . key "tags" . values . _String .
+        to (Y.array . map fromString . splitDirectories . T.unpack)
   pure $
     Y.object
       [ ("link", fromString link)
       , ("title", maybe (fromString mount) Y.String title)
+      , ("tags", Y.array tags)
       , ("text", Y.String text)
       ]