Redirect to canonical subsite/slug for post

app/Http/Controllers/Posts/PostController.php

@@ -16,6 +16,7 @@
 use App\Traits\PostTrait;
 use App\Traits\SubsiteTrait;
 use Illuminate\Contracts\View\View;
+use Illuminate\Http\RedirectResponse;
 
 final class PostController extends BaseController
 {
@@ -42,11 +43,21 @@ public function index(): View
         ]);
     }
 
-    public function show(Post $post): View
+    public function show(Post $post, ?string $slug = null): View|RedirectResponse
     {
-        $relatedPosts = $this->postRepository->getRelatedPosts($post);
-
+        // Check if the post belongs to the correct subsite
         $subdomain = $this->getSubdomain() === 'www' ? 'metafilter' : $this->getSubdomain();
+        $postSubdomain = $post->subsite->subdomain === 'www' ? 'metafilter' : $post->subsite->subdomain;
+
+        // Redirect if subdomain or slug is incorrect
+        if ($subdomain !== $postSubdomain || $slug !== $post->slug) {
+            return redirect()->route($this->getShowPostRouteName($postSubdomain), [
+                'post' => $post,
+                'slug' => $post->slug,
+            ], 301);
+        }
+
+        $relatedPosts = $this->postRepository->getRelatedPosts($post);
 
         return view('posts.show', [
             'title' => $post->title,

app/Traits/SubsiteTrait.php

@@ -157,9 +157,9 @@ public function getPostIndexRouteName(): string
         };
     }
 
-    public function getShowPostRouteName(): string
+    public function getShowPostRouteName(?string $subdomain = null): string
     {
-        $subdomain = $this->getSubdomain();
+        $subdomain ??= $this->getSubdomain();
 
         return match ($subdomain) {
             'ask' => 'ask.posts.show',

routes/subdomains/ask.php

@@ -33,7 +33,8 @@
     Route::get('', 'index')
         ->name('ask.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('ask.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/bestof.php

@@ -9,6 +9,7 @@
     Route::get('', 'index')
         ->name('bestof.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('bestof.posts.show');
 });

routes/subdomains/fanfare.php

@@ -33,7 +33,8 @@
     Route::get('', 'index')
         ->name('fanfare.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('fanfare.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/irl.php

@@ -15,7 +15,8 @@
         Route::get('', 'index')
             ->name(RouteNameEnum::IrlMyPostsIndex);
 
-        Route::get('{post}/{slug}', 'show')
+        Route::get('{post}/{slug?}', 'show')
+            ->whereNumber('post')
             ->name(RouteNameEnum::IrlMyPostsShow);
     });
 });
@@ -33,7 +34,8 @@
     Route::get('', 'index')
         ->name('irl.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('irl.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/jobs.php

@@ -25,7 +25,8 @@
     Route::get('', 'index')
         ->name('jobs.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('jobs.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/metafilter.php

@@ -122,7 +122,8 @@
     Route::get('', 'index')
         ->name('metafilter.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('metafilter.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/metatalk.php

@@ -35,7 +35,8 @@
     Route::get('', 'index')
         ->name('metatalk.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('metatalk.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/music.php

@@ -36,7 +36,8 @@
     Route::get('', 'index')
         ->name('music.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('music.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/podcast.php

@@ -31,7 +31,8 @@
     Route::get('', 'index')
         ->name('podcast.posts.index');
 
-    Route::get('{post}/{slug}', 'show')
+    Route::get('{post}/{slug?}', 'show')
+        ->whereNumber('post')
         ->name('podcast.posts.show');
 
     Route::middleware('auth')->group(function () {

routes/subdomains/projects.php

@@ -22,7 +22,8 @@
         Route::get('', 'index')
             ->name('projects.posts.index');
 
-        Route::get('{post}/{slug}', 'show')
+        Route::get('{post}/{slug?}', 'show')
+            ->whereNumber('post')
             ->name('projects.posts.show');
 
         Route::middleware('auth')->group(function () {