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source/docs/v3/tenant-attribute-encryption.blade.md

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+---
+title: Tenant attribute encryption
+extends: _layouts.documentation
+section: content
+---
+
+# Tenant attribute encryption {#encrypt}
+
+To encrypt the attributes, you must store them in [custom columns](https://tenancyforlaravel.com/docs/v3/tenants/#custom-columns). For example, we'll encrypt the tenant's database credentials (which are stored using the [Virtual Column](https://github.com/archtechx/virtualcolumn) as `tenancy_db_username` and `tenancy_db_password` by default) in a few steps.
+
+Add custom columns to the tenants migration (we recommend making the string size at least 512 characters, so it's big enough to contain the encrypted data):
+
+```php
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+class CreateTenantsTable extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up(): void
+    {
+        Schema::create('tenants', function (Blueprint $table) {
+            $table->string('id')->primary();
+
+            // Your custom columns
+            $table->string('tenancy_db_username', 512);
+            $table->string('tenancy_db_password', 512);
+
+            $table->timestamps();
+            $table->json('data')->nullable();
+        });
+    }
+}
+```
+
+Define the custom columns in the Tenant model:
+
+```php
+public static function getCustomColumns(): array
+{
+    return [
+        'id',
+        'tenancy_db_username',
+        'tenancy_db_password',
+    ];
+}
+```
+
+Then cast the attributes (using [Laravel's encrypted casts](https://laravel.com/docs/9.x/eloquent-mutators#encrypted-casting), or your custom casts) to encrypt and decrypt the attributes when needed:
+
+```php
+protected $casts = [
+    'tenancy_db_username' => 'encrypted',
+    'tenancy_db_password' => 'encrypted',
+];
+```