Fix paginated urls with custom routing (ie. when using SSG) (#288)

Author: jesseleite

src/Cascade.php

@@ -124,11 +124,17 @@ public function canonicalUrl()
     {
         $url = Str::trim($this->explicitUrl ?? $this->data->get('canonical_url'));
 
-        if (! app('request')->has('page')) {
+        if (! Str::startsWith($url, config('app.url'))) {
             return $url;
         }
 
-        $page = (int) app('request')->get('page');
+        if (! $paginator = Blink::get('tag-paginator')) {
+            return $url;
+        }
+
+        $paginator->setPath($url);
+
+        $page = $paginator->currentPage();
 
         switch (true) {
             case config('statamic.seo-pro.pagination') === false:
@@ -137,11 +143,7 @@ public function canonicalUrl()
                 return $url;
         }
 
-        if (Str::startsWith($url, config('app.url'))) {
-            $url .= '?page='.$page;
-        }
-
-        return $url;
+        return URL::makeAbsolute($paginator->url($page));
     }
 
     protected function prevUrl()
@@ -150,21 +152,25 @@ protected function prevUrl()
             return null;
         }
 
+        $url = Str::trim($this->data->get('canonical_url'));
+
+        if (! Str::startsWith($url, config('app.url'))) {
+            return $url;
+        }
+
         if (! $paginator = Blink::get('tag-paginator')) {
             return null;
         }
 
-        $url = Str::trim($this->data->get('canonical_url'));
-
-        $page = $paginator->currentPage();
-
-        if (config('statamic.seo-pro.pagination.enabled_on_first_page') === false && $page === 2) {
+        if (config('statamic.seo-pro.pagination.enabled_on_first_page') === false && $paginator->currentPage() === 2) {
             return $url;
         }
 
-        return $page > 1 && $page <= $paginator->lastPage()
-            ? $url.'?page='.($page - 1)
-            : null;
+        if (! $prevUrl = $paginator->previousPageUrl()) {
+            return null;
+        }
+
+        return URL::makeAbsolute($prevUrl);
     }
 
     protected function nextUrl()
@@ -173,17 +179,21 @@ protected function nextUrl()
             return null;
         }
 
+        $url = Str::trim($this->data->get('canonical_url'));
+
+        if (! Str::startsWith($url, config('app.url'))) {
+            return $url;
+        }
+
         if (! $paginator = Blink::get('tag-paginator')) {
             return null;
         }
 
-        $url = Str::trim($this->data->get('canonical_url'));
-
-        $page = $paginator->currentPage();
+        if (! $nextUrl = $paginator->nextPageUrl()) {
+            return null;
+        }
 
-        return $page < $paginator->lastPage()
-            ? $url.'?page='.($page + 1)
-            : null;
+        return URL::makeAbsolute($nextUrl);
     }
 
     protected function parse($key, $item)

tests/MetaTagTest.php

@@ -5,6 +5,7 @@
 use Illuminate\Pagination\LengthAwarePaginator;
 use Illuminate\Support\Facades\Artisan;
 use Illuminate\Support\Facades\Route;
+use Statamic\Extensions\Pagination\LengthAwarePaginator as StatamicLengthAwarePaginator;
 use Statamic\Facades\Blink;
 use Statamic\Facades\Collection;
 use Statamic\Facades\Config;
@@ -594,6 +595,25 @@ public function it_can_apply_pagination_to_first_page_when_configured_as_unique_
         $response->assertSee('<link href="http://cool-runnings.com/about?page=1" rel="canonical" />', false);
     }
 
+    /**
+     * @test
+     *
+     * @dataProvider viewScenarioProvider
+     *
+     * @environment-setup useFakeSsgPaginator
+     */
+    public function it_applies_custom_pagination_routing_to_meta_urls($viewType)
+    {
+        $this->withoutExceptionHandling();
+        $this->prepareViews($viewType);
+
+        $response = $this->simulatePageOutOfFive(3, FakeSsgPaginator::class);
+        $response->assertSee("<h1>{$viewType}</h1>", false);
+        $response->assertSee('<link href="http://cool-runnings.com/about/page/3" rel="canonical" />', false);
+        $response->assertSee('<link href="http://cool-runnings.com/about/page/2" rel="prev" />', false);
+        $response->assertSee('<link href="http://cool-runnings.com/about/page/4" rel="next" />', false);
+    }
+
     /**
      * @test
      *
@@ -765,10 +785,22 @@ protected function setCustomTwitterGlidePresetOnly($app)
         ]);
     }
 
-    protected function simulatePageOutOfFive($currentPage)
+    protected function simulatePageOutOfFive($currentPage, $customPaginatorClass = null)
     {
-        Blink::put('tag-paginator', new LengthAwarePaginator([], 15, 3, $currentPage));
+        $url = '/about';
+
+        $paginatorClass = $customPaginatorClass ?? LengthAwarePaginator::class;
 
-        return $this->call('GET', '/about', ['page' => $currentPage]);
+        Blink::put('tag-paginator', (new $paginatorClass([], 15, 3, $currentPage))->setPath($url));
+
+        return $this->call('GET', $url, ['page' => $currentPage]);
+    }
+}
+
+class FakeSsgPaginator extends StatamicLengthAwarePaginator
+{
+    public function url($page)
+    {
+        return \Statamic\Facades\URL::makeRelative(sprintf('%s/page/%s', $this->path(), $page));
     }
 }