Allow querying on cusotm fields fieldname directly by column name

app/Http/Controllers/Api/AssetsController.php

@@ -371,6 +371,12 @@ class AssetsController extends Controller
             $assets->where('assets.order_number', '=', strval($request->input('order_number')));
         }
 
+        foreach ($all_custom_fields as $field) {
+            if ($request->filled($field->db_column_name())) {
+                $assets->where($field->db_column_name(), '=', $request->input($field->db_column_name()));
+            }
+        }
+
         // This is kinda gross, but we need to do this because the Bootstrap Tables
         // API passes custom field ordering as custom_fields.fieldname, and we have to strip
         // that out to let the default sorter below order them correctly on the assets table.

tests/Feature/Assets/Api/AssetIndexTest.php

@@ -4,6 +4,7 @@ namespace Tests\Feature\Assets\Api;
 
 use App\Models\Asset;
 use App\Models\Company;
+use App\Models\CustomField;
 use App\Models\User;
 use Carbon\Carbon;
 use Illuminate\Testing\Fluent\AssertableJson;
@@ -168,6 +169,29 @@ class AssetIndexTest extends TestCase
             ->assertResponseContainsInRows($assetB, 'asset_tag');
     }
 
+    public function test_assets_can_be_filtered_by_custom_field()
+    {
+        $this->markIncompleteIfMySQL('Custom Fields tests do not work on MySQL');
+
+        $field = CustomField::factory()->create();
+
+        $matchingAssets = Asset::factory()->count(3)->hasMultipleCustomFields([$field])->create();
+        foreach ($matchingAssets as $asset) {
+            $asset->{$field->db_column_name()} = 'target-value';
+            $asset->save();
+        }
+
+        // These assets have a null value for the custom field column and should not be returned
+        Asset::factory()->count(2)->create();
+
+        $this->actingAsForApi(User::factory()->superuser()->create())
+            ->getJson(route('api.assets.index', [
+                $field->db_column_name() => 'target-value',
+            ]))
+            ->assertOk()
+            ->assertJson(fn (AssertableJson $json) => $json->has('rows', 3)->etc());
+    }
+
     public function test_gracefully_handles_malformed_filter()
     {
         $this->actingAsForApi(User::factory()->viewAssets()->create())