From ebde61e72a0df37ac19cee78d690c6458f4545ef Mon Sep 17 00:00:00 2001
From: Guy Sartorelli <36352093+GuySartorelli@users.noreply.github.com>
Date: Thu, 30 Nov 2023 13:01:54 +1300
Subject: [PATCH] NEW Configuration property for disallowed status codes (#178)

---
 docs/en/basic_configuration.md                  | 12 ++++++++++++
 src/Publisher/FilesystemPublisher.php           | 16 ++++++++++++++++
 tests/php/Publisher/FilesystemPublisherTest.php | 11 +++++++++++
 3 files changed, 39 insertions(+)

diff --git a/docs/en/basic_configuration.md b/docs/en/basic_configuration.md
index 0bf0005f..f11b8ed7 100644
--- a/docs/en/basic_configuration.md
+++ b/docs/en/basic_configuration.md
@@ -48,6 +48,18 @@ class MyFormPage extends Page
 }
 ```
 
+## Excluding response codes
+
+Be default, static files are generated for all page responses regardless of the response's status code.
+If you would like to exclude certain status codes from being statically cached, set the `FilesystemPublisher.disallowed_status_codes` configuration property:
+
+```yaml
+SilverStripe\StaticPublishQueue\Publisher\FilesystemPublisher:
+  disallowed_status_codes:
+    - 404
+    - 500
+```
+
 ## Control when child/parent pages are regenerated in cache actions
 
 There are two configurations available, and they can both be set to one of three available values:
diff --git a/src/Publisher/FilesystemPublisher.php b/src/Publisher/FilesystemPublisher.php
index ca9084fd..63e0c49a 100644
--- a/src/Publisher/FilesystemPublisher.php
+++ b/src/Publisher/FilesystemPublisher.php
@@ -12,6 +12,11 @@
 
 class FilesystemPublisher extends Publisher
 {
+    /**
+     * Status codes that aren't allowed to be statically cached.
+     */
+    private static array $disallowed_status_codes = [];
+
     /**
      * @var string
      */
@@ -108,6 +113,17 @@ public function publishURL($url, $forcePublish = false)
         $statusCode = $response->getStatusCode();
         $doPublish = ($forcePublish && $this->getFileExtension() === 'php') || $statusCode < 400;
 
+        // Don't statically cache if the status code is in a deny list
+        if (in_array($statusCode, static::config()->get('disallowed_status_codes'))) {
+            return [
+                'published' => false,
+                // Considering this a "success" since the behaviour is as expected
+                'success' => true,
+                'responsecode' => $statusCode,
+                'url' => $url,
+            ];
+        }
+
         if ($statusCode >= 300 && $statusCode < 400) {
             // publish redirect response
             $success = $this->publishRedirect($response, $url);
diff --git a/tests/php/Publisher/FilesystemPublisherTest.php b/tests/php/Publisher/FilesystemPublisherTest.php
index 486b3b16..73a9df27 100644
--- a/tests/php/Publisher/FilesystemPublisherTest.php
+++ b/tests/php/Publisher/FilesystemPublisherTest.php
@@ -246,6 +246,17 @@ public function testPurgeURLAfterSwitchingExtensions(): void
         $this->assertFileDoesNotExist($this->fsp->getDestPath() . 'purge-me.php');
     }
 
+    public function testNoPublishOnDisallowedResponseCode(): void
+    {
+        $this->logOut();
+
+        FilesystemPublisher::config()->set('disallowed_status_codes', [404]);
+
+        $this->fsp->publishURL('not_really_there', true);
+        $this->assertFileDoesNotExist($this->fsp->getDestPath() . 'not_really_there.html');
+        $this->assertFileDoesNotExist($this->fsp->getDestPath() . 'not_really_there.php');
+    }
+
     public function testNoErrorPagesWhenHTMLOnly(): void
     {
         $this->logOut();