feat: Default Settings Extender (#3127)

Co-authored-by: Alexander Skvortsov <38059171+askvortsov1@users.noreply.github.com>

framework/core/src/Database/Migration.php

@@ -9,6 +9,7 @@
 
 namespace Flarum\Database;
 
+use Flarum\Extend\Settings;
 use Flarum\Settings\DatabaseSettingsRepository;
 use Illuminate\Database\Schema\Blueprint;
 use Illuminate\Database\Schema\Builder;
@@ -120,6 +121,9 @@ abstract class Migration
 
     /**
      * Add default values for config values.
+     *
+     * @deprecated Use the Settings extender's `default` method instead to register settings.
+     * @see Settings::default()
      */
     public static function addSettings(array $defaults)
     {

framework/core/src/Extend/Settings.php

@@ -15,10 +15,12 @@ use Flarum\Extension\Extension;
 use Flarum\Foundation\ContainerUtil;
 use Flarum\Settings\SettingsRepositoryInterface;
 use Illuminate\Contracts\Container\Container;
+use Illuminate\Support\Collection;
 
 class Settings implements ExtenderInterface
 {
     private $settings = [];
+    private $defaults = [];
 
     /**
      * Serialize a setting value to the ForumSerializer attributes.
@@ -33,7 +35,8 @@ class Settings implements ExtenderInterface
      * The callable should return:
      * - mixed $value: The modified value.
      *
-     * @param mixed $default: Optional default serialized value. Will be run through the optional callback.
+     * @todo remove $default in 2.0
+     * @param mixed $default: Deprecated optional default serialized value. Will be run through the optional callback.
      * @return self
      */
     public function serializeToForum(string $attributeName, string $key, $callback = null, $default = null): self
@@ -43,8 +46,35 @@ class Settings implements ExtenderInterface
         return $this;
     }
 
+    /**
+     * Set a default value for a setting.
+     * Replaces inserting the default value with a migration.
+     *
+     * @param string $key: The setting key, must be unique. Namespace it with the extension ID (example: 'my-extension-id.setting_key').
+     * @param mixed $value: The setting value.
+     * @return self
+     */
+    public function default(string $key, $value): self
+    {
+        $this->defaults[$key] = $value;
+
+        return $this;
+    }
+
     public function extend(Container $container, Extension $extension = null)
     {
+        if (! empty($this->defaults)) {
+            $container->extend('flarum.settings.default', function (Collection $defaults) {
+                foreach ($this->defaults as $key => $value) {
+                    if ($defaults->has($key)) {
+                        throw new \RuntimeException("Cannot modify immutable default setting $key.");
+                    }
+
+                    $defaults->put($key, $value);
+                }
+            });
+        }
+
         if (! empty($this->settings)) {
             AbstractSerializer::addAttributeMutator(
                 ForumSerializer::class,

framework/core/src/Settings/DefaultSettingsRepository.php

@@ -0,0 +1,47 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Settings;
+
+use Illuminate\Support\Collection;
+
+class DefaultSettingsRepository implements SettingsRepositoryInterface
+{
+    protected $defaults;
+
+    private $inner;
+
+    public function __construct(SettingsRepositoryInterface $inner, Collection $defaults)
+    {
+        $this->inner = $inner;
+        $this->defaults = $defaults;
+    }
+
+    public function get($key, $default = null)
+    {
+        // Global default overrules local default because local default is deprecated,
+        // and will be removed in 2.0
+        return $this->inner->get($key, $this->defaults->get($key, $default));
+    }
+
+    public function set($key, $value)
+    {
+        $this->inner->set($key, $value);
+    }
+
+    public function delete($keyLike)
+    {
+        $this->inner->delete($keyLike);
+    }
+
+    public function all(): array
+    {
+        return array_merge($this->defaults->toArray(), $this->inner->all());
+    }
+}

framework/core/src/Settings/SettingsRepositoryInterface.php

@@ -13,6 +13,13 @@ interface SettingsRepositoryInterface
 {
     public function all(): array;
 
+    /**
+     * @todo remove $default in 2.0
+     *
+     * @param $key
+     * @param mixed $default: Deprecated
+     * @return mixed
+     */
     public function get($key, $default = null);
 
     public function set($key, $value);

framework/core/src/Settings/SettingsServiceProvider.php

@@ -12,6 +12,7 @@ namespace Flarum\Settings;
 use Flarum\Foundation\AbstractServiceProvider;
 use Illuminate\Contracts\Container\Container;
 use Illuminate\Database\ConnectionInterface;
+use Illuminate\Support\Collection;
 
 class SettingsServiceProvider extends AbstractServiceProvider
 {
@@ -20,11 +21,18 @@ class SettingsServiceProvider extends AbstractServiceProvider
      */
     public function register()
     {
+        $this->container->singleton('flarum.settings.default', function () {
+            return new Collection();
+        });
+
         $this->container->singleton(SettingsRepositoryInterface::class, function (Container $container) {
-            return new MemoryCacheSettingsRepository(
-                new DatabaseSettingsRepository(
-                    $container->make(ConnectionInterface::class)
-                )
+            return new DefaultSettingsRepository(
+                new MemoryCacheSettingsRepository(
+                    new DatabaseSettingsRepository(
+                        $container->make(ConnectionInterface::class)
+                    )
+                ),
+                $container->make('flarum.settings.default')
             );
         });
 

framework/core/tests/integration/extenders/SettingsTest.php

@@ -163,6 +163,63 @@ class SettingsTest extends TestCase
         $this->assertArrayHasKey('customPrefix.noCustomSetting', $payload['data']['attributes']);
         $this->assertEquals('customDefaultModified2', $payload['data']['attributes']['customPrefix.noCustomSetting']);
     }
+
+    /**
+     * @test
+     */
+    public function custom_setting_default_prioritizes_extender()
+    {
+        $this->extend(
+            (new Extend\Settings())
+                ->serializeToForum('customPrefix.unavailableCustomSetting3', 'custom-prefix.unavailable_custom_setting3')
+                ->default('custom-prefix.unavailable_custom_setting3', 'extenderDefault')
+        );
+
+        $value = $this->app()
+            ->getContainer()
+            ->make('flarum.settings')
+            ->get('custom-prefix.unavailable_custom_setting3', 'defaultParameterValue');
+
+        $this->assertEquals('extenderDefault', $value);
+    }
+
+    /**
+     * @test
+     */
+    public function custom_setting_default_falls_back_to_parameter()
+    {
+        $this->extend(
+            (new Extend\Settings())
+                ->serializeToForum('customPrefix.unavailableCustomSetting4', 'custom-prefix.unavailable_custom_setting4')
+        );
+
+        $value = $this->app()
+            ->getContainer()
+            ->make('flarum.settings')
+            ->get('custom-prefix.unavailable_custom_setting4', 'defaultParameterValue');
+
+        $this->assertEquals('defaultParameterValue', $value);
+    }
+
+    /**
+     * @test
+     */
+    public function null_custom_setting_returns_null()
+    {
+        $this->setting('custom-prefix.custom_null_setting', null);
+
+        $this->extend(
+            (new Extend\Settings())
+                ->default('custom-prefix.custom_null_setting', 'extenderDefault')
+        );
+
+        $value = $this->app()
+            ->getContainer()
+            ->make('flarum.settings')
+            ->get('custom-prefix.custom_null_setting');
+
+        $this->assertEquals(null, $value);
+    }
 }
 
 class CustomInvokableClass