Syncing: move global ID generation logic to an overridable method

Also make all resource syncing-related listener closures static.

Also correct return type for getGlobalIdentifierKey to string|int.
(We intentionally do not support returning null like many other
"get x key" methods would since such a case might break resource
syncing logic. This is also why we use inline getAttribute() in the
creating listener instead of calling the method.)

assets/TenancyServiceProvider.stub.php

@@ -81,6 +81,8 @@ class TenancyServiceProvider extends ServiceProvider
                 ])->send(function (Events\TenantDeleted $event) {
                     return $event->tenant;
                 })->shouldBeQueued(false),
+
+                // ResourceSyncing\Listeners\DeleteAllTenantMappings::class,
             ],
 
             Events\TenantMaintenanceModeEnabled::class => [],
@@ -129,6 +131,9 @@ class TenancyServiceProvider extends ServiceProvider
             ResourceSyncing\Events\SyncedResourceSaved::class => [
                 ResourceSyncing\Listeners\UpdateOrCreateSyncedResource::class,
             ],
+            ResourceSyncing\Events\SyncedResourceDeleted::class => [
+                ResourceSyncing\Listeners\DeleteResourceMapping::class,
+            ],
             ResourceSyncing\Events\SyncMasterDeleted::class => [
                 ResourceSyncing\Listeners\DeleteResourcesInTenants::class,
             ],

src/ResourceSyncing/Events/SyncedResourceDeleted.php

@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Stancl\Tenancy\ResourceSyncing\Events;
+
+use Illuminate\Database\Eloquent\Model;
+use Stancl\Tenancy\Database\Contracts\TenantWithDatabase;
+use Stancl\Tenancy\ResourceSyncing\Syncable;
+
+class SyncedResourceDeleted
+{
+    public function __construct(
+        public Syncable&Model $model,
+        public TenantWithDatabase|null $tenant,
+        public bool $forceDelete,
+    ) {}
+}

src/ResourceSyncing/Listeners/DeleteAllTenantMappings.php

@@ -0,0 +1,48 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Stancl\Tenancy\ResourceSyncing\Listeners;
+
+use Illuminate\Support\Facades\DB;
+use Stancl\Tenancy\Events\TenantDeleted;
+use Stancl\Tenancy\Listeners\QueueableListener;
+
+/**
+ * Clean up pivot records related to the deleted tenant.
+ * The listener only cleans up the pivot tables specified
+ * in the $pivotTables property (see the property for details),
+ * and is intended for use with tables that do not have tenant foreign key constraints.
+ *
+ * When using foreign key constraints, you'll still have to use ->onDelete('cascade')
+ * on the constraint (otherwise, deleting a tenant will throw a foreign key constraint violation).
+ * That way, the cleanup will happen on the database level, and this listener will essentially
+ * just perform an extra 'where' query.
+ */
+class DeleteAllTenantMappings extends QueueableListener
+{
+    /**
+     * Pivot tables to clean up after a tenant is deleted,
+     * formatted like ['table_name' => 'tenant_key_column'].
+     *
+     * Since we cannot automatically detect which pivot tables
+     * you want to clean up, they have to be specified here.
+     *
+     * By default, resource syncing uses the tenant_resources table, and the records are associated
+     * to tenants by the tenant_id column (thus the ['tenant_resources' => 'tenant_id'] default).
+     *
+     * To customize this, set this property, e.g. in TenancyServiceProvider:
+     * DeleteAllTenantMappings::$pivotTables = [
+     *     'tenant_users' => 'tenant_id',
+     *     // You can also add more pivot tables here
+     * ];
+     */
+    public static array $pivotTables = ['tenant_resources' => 'tenant_id'];
+
+    public function handle(TenantDeleted $event): void
+    {
+        foreach (static::$pivotTables as $table => $tenantKeyColumn) {
+            DB::table($table)->where($tenantKeyColumn, $event->tenant->getTenantKey())->delete();
+        }
+    }
+}

src/ResourceSyncing/Listeners/DeleteResourceMapping.php

@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Stancl\Tenancy\ResourceSyncing\Listeners;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\Pivot;
+use Illuminate\Database\Eloquent\SoftDeletes;
+use Stancl\Tenancy\Listeners\QueueableListener;
+use Stancl\Tenancy\ResourceSyncing\Events\SyncedResourceDeleted;
+use Stancl\Tenancy\ResourceSyncing\Syncable;
+use Stancl\Tenancy\ResourceSyncing\SyncMaster;
+
+/**
+ * Deletes pivot records when a synced resource is deleted.
+ *
+ * If a SyncMaster (central resource) is deleted, all pivot records for that resource are deleted.
+ * If a Syncable (tenant resource) is deleted, only delete the pivot record for that tenant.
+ */
+class DeleteResourceMapping extends QueueableListener
+{
+    public static bool $shouldQueue = false;
+
+    public function handle(SyncedResourceDeleted $event): void
+    {
+        $centralResource = $this->getCentralResource($event->model);
+
+        if (! $centralResource) {
+            return;
+        }
+
+        // Delete pivot records if the central resource doesn't use soft deletes
+        // or the central resource was deleted using forceDelete()
+        if ($event->forceDelete || ! in_array(SoftDeletes::class, class_uses_recursive($centralResource::class), true)) {
+            Pivot::withoutEvents(function () use ($centralResource, $event) {
+                // $event->tenant is null when the deleted resource is a SyncMaster - all mappings are deleted in that case
+                // When $event->tenant is not null (= a Syncable was deleted), only delete the mapping for that tenant
+                $centralResource->tenants()->detach($event->tenant);
+            });
+        }
+    }
+
+    public function getCentralResource(Syncable&Model $resource): SyncMaster|null
+    {
+        if ($resource instanceof SyncMaster) {
+            return $resource;
+        }
+
+        $centralResourceClass = $resource->getCentralModelName();
+
+        /** @var (SyncMaster&Model)|null $centralResource */
+        $centralResource = $centralResourceClass::firstWhere(
+            $resource->getGlobalIdentifierKeyName(),
+            $resource->getGlobalIdentifierKey()
+        );
+
+        return $centralResource;
+    }
+}

src/ResourceSyncing/Listeners/DeleteResourcesInTenants.php

@@ -4,7 +4,6 @@ declare(strict_types=1);
 
 namespace Stancl\Tenancy\ResourceSyncing\Listeners;
 
-use Illuminate\Database\Eloquent\SoftDeletes;
 use Stancl\Tenancy\Listeners\QueueableListener;
 use Stancl\Tenancy\ResourceSyncing\Events\SyncMasterDeleted;
 
@@ -21,12 +20,6 @@ class DeleteResourcesInTenants extends QueueableListener
 
         tenancy()->runForMultiple($centralResource->tenants()->cursor(), function () use ($centralResource, $forceDelete) {
             $this->deleteSyncedResource($centralResource, $forceDelete);
-
-            // Delete pivot records if the central resource doesn't use soft deletes
-            // or the central resource was deleted using forceDelete()
-            if ($forceDelete || ! in_array(SoftDeletes::class, class_uses_recursive($centralResource::class), true)) {
-                $centralResource->tenants()->detach(tenant());
-            }
         });
     }
 }

src/ResourceSyncing/ResourceSyncing.php

@@ -11,6 +11,7 @@ use Stancl\Tenancy\Contracts\UniqueIdentifierGenerator;
 use Stancl\Tenancy\Database\Contracts\TenantWithDatabase;
 use Stancl\Tenancy\ResourceSyncing\Events\CentralResourceAttachedToTenant;
 use Stancl\Tenancy\ResourceSyncing\Events\CentralResourceDetachedFromTenant;
+use Stancl\Tenancy\ResourceSyncing\Events\SyncedResourceDeleted;
 use Stancl\Tenancy\ResourceSyncing\Events\SyncedResourceSaved;
 use Stancl\Tenancy\ResourceSyncing\Events\SyncMasterDeleted;
 use Stancl\Tenancy\ResourceSyncing\Events\SyncMasterRestored;
@@ -19,36 +20,33 @@ trait ResourceSyncing
 {
     public static function bootResourceSyncing(): void
     {
-        static::saved(function (Syncable&Model $model) {
+        static::saved(static function (Syncable&Model $model) {
             if ($model->shouldSync() && ($model->wasRecentlyCreated || $model->wasChanged($model->getSyncedAttributeNames()))) {
                 $model->triggerSyncEvent();
             }
         });
 
-        static::deleting(function (Syncable&Model $model) {
+        static::deleted(static function (Syncable&Model $model) {
-            if ($model->shouldSync() && $model instanceof SyncMaster) {
+            if ($model->shouldSync()) {
                 $model->triggerDeleteEvent();
             }
         });
 
-        static::creating(function (Syncable&Model $model) {
+        static::creating(static function (Syncable&Model $model) {
-            if (! $model->getAttribute($model->getGlobalIdentifierKeyName()) && app()->bound(UniqueIdentifierGenerator::class)) {
+            if (! $model->getAttribute($model->getGlobalIdentifierKeyName())) {
-                $model->setAttribute(
+                $model->generateGlobalIdentifierKey();
-                    $model->getGlobalIdentifierKeyName(),
-                    app(UniqueIdentifierGenerator::class)->generate($model)
-                );
             }
         });
 
         if (in_array(SoftDeletes::class, class_uses_recursive(static::class), true)) {
-            static::forceDeleting(function (Syncable&Model $model) {
+            static::forceDeleting(static function (Syncable&Model $model) {
-                if ($model->shouldSync() && $model instanceof SyncMaster) {
+                if ($model->shouldSync()) {
                     $model->triggerDeleteEvent(true);
                 }
             });
 
-            static::restoring(function (Syncable&Model $model) {
+            static::restoring(static function (Syncable&Model $model) {
-                if ($model->shouldSync() && $model instanceof SyncMaster) {
+                if ($model->shouldSync()) {
                     $model->triggerRestoredEvent();
                 }
             });
@@ -67,6 +65,8 @@ trait ResourceSyncing
             /** @var SyncMaster&Model $this */
             event(new SyncMasterDeleted($this, $forceDelete));
         }
+
+        event(new SyncedResourceDeleted($this, tenant(), $forceDelete));
     }
 
     public function triggerRestoredEvent(): void
@@ -116,8 +116,18 @@ trait ResourceSyncing
         return 'global_id';
     }
 
-    public function getGlobalIdentifierKey(): string
+    public function getGlobalIdentifierKey(): string|int
     {
         return $this->getAttribute($this->getGlobalIdentifierKeyName());
     }
+
+    protected function generateGlobalIdentifierKey(): void
+    {
+        if (! app()->bound(UniqueIdentifierGenerator::class)) return;
+
+        $this->setAttribute(
+            $this->getGlobalIdentifierKeyName(),
+            app(UniqueIdentifierGenerator::class)->generate($this),
+        );
+    }
 }

src/ResourceSyncing/SyncMaster.php

@@ -25,7 +25,5 @@ interface SyncMaster extends Syncable
 
     public function triggerAttachEvent(TenantWithDatabase&Model $tenant): void;
 
-    public function triggerDeleteEvent(bool $forceDelete = false): void;
-
     public function triggerRestoredEvent(): void;
 }

src/ResourceSyncing/Syncable.php

@@ -16,6 +16,8 @@ interface Syncable
 
     public function triggerSyncEvent(): void;
 
+    public function triggerDeleteEvent(bool $forceDelete = false): void;
+
     /**
      * Get the attributes used for creating the *other* model (i.e. tenant if this is the central one, and central if this is the tenant one).
      *

src/ResourceSyncing/TriggerSyncingEvents.php

@@ -20,14 +20,14 @@ trait TriggerSyncingEvents
 {
     public static function bootTriggerSyncingEvents(): void
     {
-        static::saving(function (self $pivot) {
+        static::saving(static function (self $pivot) {
             // Try getting the central resource to see if it is available
             // If it is not available, throw an exception to interrupt the saving process
             // And prevent creating a pivot record without a central resource
             $pivot->getCentralResourceAndTenant();
         });
 
-        static::saved(function (self $pivot) {
+        static::saved(static function (self $pivot) {
             /**
              * @var static&Pivot $pivot
              * @var SyncMaster|null $centralResource
@@ -40,7 +40,7 @@ trait TriggerSyncingEvents
             }
         });
 
-        static::deleting(function (self $pivot) {
+        static::deleting(static function (self $pivot) {
             /**
              * @var static&Pivot $pivot
              * @var SyncMaster|null $centralResource

tests/Etc/ResourceSyncing/CentralUser.php

@@ -12,6 +12,7 @@ use Stancl\Tenancy\ResourceSyncing\SyncMaster;
 class CentralUser extends Model implements SyncMaster
 {
     use ResourceSyncing, CentralConnection;
+
     protected $guarded = [];
 
     public $timestamps = false;

tests/Etc/synced_resource_migrations/2020_05_11_000002_create_tenant_users_table.php

@@ -16,9 +16,6 @@ class CreateTenantUsersTable extends Migration
             $table->string('global_user_id');
 
             $table->unique(['tenant_id', 'global_user_id']);
-
-            $table->foreign('tenant_id')->references('id')->on('tenants')->onUpdate('cascade')->onDelete('cascade');
-            $table->foreign('global_user_id')->references('global_id')->on('users')->onUpdate('cascade')->onDelete('cascade');
         });
     }
 

tests/ResourceSyncingTest.php

@@ -46,6 +46,12 @@ use Stancl\Tenancy\ResourceSyncing\Events\SyncedResourceSavedInForeignDatabase;
 use Illuminate\Database\Eloquent\Scope;
 use Illuminate\Database\QueryException;
 use function Stancl\Tenancy\Tests\pest;
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Database\Schema\Blueprint;
+use Stancl\Tenancy\Events\TenantDeleted;
+use Stancl\Tenancy\ResourceSyncing\Events\SyncedResourceDeleted;
+use Stancl\Tenancy\ResourceSyncing\Listeners\DeleteAllTenantMappings;
+use Stancl\Tenancy\ResourceSyncing\Listeners\DeleteResourceMapping;
 
 beforeEach(function () {
     config(['tenancy.bootstrappers' => [
@@ -69,6 +75,7 @@ beforeEach(function () {
     CreateTenantResource::$shouldQueue = false;
     DeleteResourceInTenant::$shouldQueue = false;
     UpdateOrCreateSyncedResource::$scopeGetModelQuery = null;
+    DeleteAllTenantMappings::$pivotTables = ['tenant_resources' => 'tenant_id'];
 
     // Reset global scopes on models (should happen automatically but to make this more explicit)
     Model::clearBootedModels();
@@ -92,6 +99,7 @@ beforeEach(function () {
     CentralUser::$creationAttributes = $creationAttributes;
 
     Event::listen(SyncedResourceSaved::class, UpdateOrCreateSyncedResource::class);
+    Event::listen(SyncedResourceDeleted::class, DeleteResourceMapping::class);
     Event::listen(SyncMasterDeleted::class, DeleteResourcesInTenants::class);
     Event::listen(SyncMasterRestored::class, RestoreResourcesInTenants::class);
     Event::listen(CentralResourceAttachedToTenant::class, CreateTenantResource::class);
@@ -890,7 +898,54 @@ test('deleting SyncMaster automatically deletes its Syncables', function (bool $
     'basic pivot' => false,
 ]);
 
-test('tenant pivot records are deleted along with the tenants to which they belong to', function() {
+test('tenant pivot records are deleted along with the tenants to which they belong to', function (bool $dbLevelOnCascadeDelete, bool $morphPivot) {
+    [$tenant] = createTenantsAndRunMigrations();
+
+    if ($morphPivot) {
+        config(['tenancy.models.tenant' => MorphTenant::class]);
+        $centralUserModel = BaseCentralUser::class;
+
+        // The default pivot table, no need to configure the listener
+        $pivotTable = 'tenant_resources';
+    } else {
+        $centralUserModel = CentralUser::class;
+
+        // Custom pivot table
+        $pivotTable = 'tenant_users';
+    }
+
+    if ($dbLevelOnCascadeDelete) {
+        addTenantIdConstraintToPivot($pivotTable);
+    } else {
+        // Event-based cleanup
+        Event::listen(TenantDeleted::class, DeleteAllTenantMappings::class);
+
+        DeleteAllTenantMappings::$pivotTables = [$pivotTable => 'tenant_id'];
+    }
+
+    $syncMaster = $centralUserModel::create([
+        'global_id' => 'user',
+        'name' => 'Central user',
+        'email' => 'central@localhost',
+        'password' => 'password',
+        'role' => 'user',
+    ]);
+
+    $syncMaster->tenants()->attach($tenant);
+
+    // Pivot records should be deleted along with the tenant
+    $tenant->delete();
+
+    expect(DB::select("SELECT * FROM {$pivotTable} WHERE tenant_id = ?", [$tenant->getTenantKey()]))->toHaveCount(0);
+})->with([
+    'db level on cascade delete' => true,
+    'event-based on cascade delete' => false,
+])->with([
+    'polymorphic pivot' => true,
+    'basic pivot' => false,
+]);
+
+test('pivot record is automatically deleted with the tenant resource', function() {
     [$tenant] = createTenantsAndRunMigrations();
 
     $syncMaster = CentralUser::create([
@@ -903,10 +958,32 @@ test('tenant pivot records are deleted along with the tenants to which they belo
 
     $syncMaster->tenants()->attach($tenant);
 
-    $tenant->delete();
+    expect(DB::select("SELECT * FROM tenant_users WHERE tenant_id = ?", [$tenant->id]))->toHaveCount(1);
 
-    // Deleting tenant deletes its pivot records
+    $tenant->run(function () {
-    expect(DB::select("SELECT * FROM tenant_users WHERE tenant_id = ?", [$tenant->getTenantKey()]))->toHaveCount(0);
+        TenantUser::firstWhere('global_id', 'cascade_user')->delete();
+    });
+
+    // Deleting tenant resource deletes its pivot record
+    expect(DB::select("SELECT * FROM tenant_users WHERE tenant_id = ?", [$tenant->id]))->toHaveCount(0);
+});
+
+test('DeleteAllTenantMappings handles incorrect configuration correctly', function() {
+    Event::listen(TenantDeleted::class, DeleteAllTenantMappings::class);
+
+    [$tenant1, $tenant2] = createTenantsAndRunMigrations();
+
+    // Existing table, non-existent tenant key column
+    // The listener should throw an 'unknown column' exception
+    DeleteAllTenantMappings::$pivotTables = ['tenant_users' => 'non_existent_column'];
+
+    // Should throw an exception when tenant is deleted
+    expect(fn() => $tenant1->delete())->toThrow(QueryException::class, "Unknown column 'non_existent_column' in 'where clause'");
+
+    // Non-existent table
+    DeleteAllTenantMappings::$pivotTables = ['nonexistent_pivot' => 'non_existent_column'];
+
+    expect(fn() => $tenant2->delete())->toThrow(QueryException::class, "Table 'main.nonexistent_pivot' doesn't exist");
 });
 
 test('trashed resources are synced correctly', function () {
@@ -1265,6 +1342,13 @@ test('global scopes on syncable models can break resource syncing', function ()
     expect($tenant1->run(fn () => TenantUser::first()->name))->toBe('tenant2 user');
 });
 
+function addTenantIdConstraintToPivot(string $pivotTable): void
+{
+    Schema::table($pivotTable, function (Blueprint $table) {
+        $table->foreign('tenant_id')->references('id')->on('tenants')->onDelete('cascade');
+    });
+}
+
 /**
  * Create two tenants and run migrations for those tenants.
  *