AI: address issue #436

backend/app/services/post_tag_search.rb

@@ -3,8 +3,8 @@ class PostTagSearch
   def self.literals(locale, raw)
     tokens = raw.split.reject { _1.downcase == 'type:or' }
     names = tokens.map { _1.sub(/\Anot:/i, '') }
-    registered = matching_names(TagName.where(language_code: locale.language_code),
+    registered = TagName.where(language_code: locale.language_code, name: names)
-        names, 'tag_names.name', :tag_id).to_h
+        .pluck(:name, :tag_id).to_h
     primary = TagName.where(language_code: locale.language_code,
         tag_id: registered.values, primary_flg: true).pluck(:tag_id, :name).to_h
     tokens.zip(names).map do |token, name|
@@ -19,25 +19,12 @@ class PostTagSearch
 
   def self.references_for(locale, literals)
     names = literals.map { _1[:name] }.uniq
-    internal = matching_names(TagName.where(language_code: locale.language_code),
+    internal = TagName.where(language_code: locale.language_code, name: names)
-        names, 'tag_names.name', :tag_id).group_by(&:first)
+        .pluck(:name, :tag_id).group_by(&:first)
-    external = matching_names(ExternalTag.all, names,
+    external = names.empty? ? {} : ExternalTag.where(
-        "CONCAT(external_tags.platform, ':', external_tags.name)", :id).group_by(&:first)
+        "CONCAT(platform, ':', name) IN (?)", names)
+        .pluck(Arel.sql("CONCAT(platform, ':', name)"), :id).group_by(&:first)
     names.to_h { |name| [name, [internal.fetch(name, []).map(&:last).uniq,
                               external.fetch(name, []).map(&:last).uniq]] }
   end
-
-  def self.matching_names(scope, names, expression, identifier)
-    return [] if names.empty?
-
-    queries = names.uniq.map do |name|
-      scope.klass.sanitize_sql_array(['SELECT ? AS name', name])
-    end
-    # Return the input spelling so Ruby does not recheck database equivalence.
-    scope.joins(<<~SQL).pluck(Arel.sql('search_names.name'), identifier)
-      INNER JOIN (#{ queries.join(' UNION ALL ') }) AS search_names
-        ON #{ expression } = search_names.name COLLATE utf8mb4_0900_ai_ci
-    SQL
-  end
-  private_class_method :matching_names
 end

frontend/src/entry-server.tsx

@@ -1,6 +1,6 @@
 import { QueryClient, QueryClientProvider, dehydrate, skipToken } from '@tanstack/react-query'
 import { PassThrough } from 'node:stream'
-import { renderToPipeableStream } from 'react-dom/server'
+import { renderToPipeableStream, renderToStaticMarkup } from 'react-dom/server'
 import { HelmetProvider } from 'react-helmet-async'
 import { I18nextProvider } from 'react-i18next'
 import { createStaticHandler, createStaticRouter,
@@ -9,7 +9,7 @@ import { createStaticHandler, createStaticRouter,
 import { AppFrame, appRoutes, resolvePageRoute } from '@/App'
 import { apiGet, isApiError } from '@/lib/api'
 import { createUII18n } from '@/lib/i18n'
-import { fetchLocales, isLocaleCode, legacyLocalePath } from '@/lib/locales'
+import { fetchLocales, isLocaleCode, legacyLocalePath, switchLocalePath } from '@/lib/locales'
 import { localesKeys, sessionKeys } from '@/lib/queryKeys'
 import { withRenderContext } from '@/lib/renderContext.server'
 
@@ -171,8 +171,26 @@ export const render = async (
 	}))
       }
       const helmet = helmetContext.helmet!
+      const alternates = status === 200 && known != null
+	  ? await Promise.all (locales.locales.map (entry => entry.code)
+	      .filter (isLocaleCode)
+	      .filter (code => known.route.handle?.locale == null
+		  || known.route.handle.locale === code)
+	      .map (async targetLocale => {
+		const location = { pathname: url.pathname, search: url.search, hash: '' }
+		const path = targetLocale === locale
+		    ? url.pathname + url.search
+		    : (known.route.handle?.switchLocale != null
+		       ? await known.route.handle.switchLocale ({
+			   location, params: known.params, locale, targetLocale })
+		       : switchLocalePath (location, targetLocale))
+		return <link key={targetLocale} rel="alternate" hrefLang={targetLocale}
+		    href={new URL (path, origin).href}/>
+	      }))
+	  : []
       const head = [helmet.title, helmet.meta, helmet.link, helmet.style]
 	  .map (entry => entry.toString ()).join ('')
+	  + renderToStaticMarkup (<>{alternates}</>)
       const dehydrated = dehydrate (client, { shouldDehydrateQuery: query =>
 	  query.state.status !== 'pending'
 	  && query.meta?.clientOnly !== true