Access nested inputs with dot notation in find option of @can #1216

CHANGELOG.md

@@ -11,6 +11,7 @@ You can find and compare releases at the [GitHub release page](https://github.co
 
 ### Added
 
+- Access nested inputs with dot notation using the `find` option of `@can` https://github.com/nuwave/lighthouse/pull/1216
 - Add `@hash` directive which uses Laravel's hashing configuration https://github.com/nuwave/lighthouse/pull/1200
 - Add option `passOrdered` to `@method` to pass just the arguments as ordered parameters https://github.com/nuwave/lighthouse/pull/1208
 

docs/4.9/api-reference/directives.md

@@ -452,6 +452,8 @@ directive @can(
   """
   The name of the argument that is used to find a specific model
   instance against which the permissions should be checked.
+
+  You may pass the string as a dot notation to search in a array.
   """
   find: String
 

src/Schema/Directives/CanDirective.php

@@ -6,7 +6,9 @@
 use GraphQL\Type\Definition\ResolveInfo;
 use Illuminate\Contracts\Auth\Access\Gate;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Support\Arr;
 use Nuwave\Lighthouse\Exceptions\AuthorizationException;
+use Nuwave\Lighthouse\Exceptions\DefinitionException;
 use Nuwave\Lighthouse\Execution\Arguments\ArgumentSet;
 use Nuwave\Lighthouse\Schema\Values\FieldValue;
 use Nuwave\Lighthouse\SoftDeletes\ForceDeleteDirective;
@@ -52,6 +54,8 @@ public static function definition(): string
   """
   The name of the argument that is used to find a specific model
   instance against which the permissions should be checked.
+
+  You may pass the string as a dot notation to search in a array.
   """
   find: String
 
@@ -115,6 +119,10 @@ function ($root, array $args, GraphQLContext $context, ResolveInfo $resolveInfo)
     protected function modelsToCheck(ArgumentSet $argumentSet, array $args): iterable
     {
         if ($find = $this->directiveArgValue('find')) {
+            if (($findValue = Arr::get($args, $find)) === null) {
+                throw new DefinitionException("Could not find key: \"${find}\". The key must be a non-null field");
+            }
+
             $queryBuilder = $this->getModelClass()::query();
 
             $directivesContainsForceDelete = $argumentSet->directives->contains(
@@ -143,7 +151,7 @@ function (Directive $directive): bool {
                         return $directive instanceof TrashedDirective;
                     }
                 )
-                ->findOrFail($args[$find]);
+                ->findOrFail($findValue);
 
             if ($modelOrModels instanceof Model) {
                 $modelOrModels = [$modelOrModels];

tests/Integration/Schema/Directives/CanDirectiveDBTest.php

@@ -4,6 +4,7 @@
 
 use Illuminate\Database\Eloquent\ModelNotFoundException;
 use Nuwave\Lighthouse\Exceptions\AuthorizationException;
+use Nuwave\Lighthouse\Exceptions\DefinitionException;
 use Tests\DBTestCase;
 use Tests\Utils\Models\Post;
 use Tests\Utils\Models\Task;
@@ -87,6 +88,117 @@ public function testFailsToFindSpecificModel(): void
         ');
     }
 
+    public function testThrowsIfInvalidFindKey()
+    {
+        $this->be(
+            new User([
+                'name' => UserPolicy::ADMIN,
+            ])
+        );
+
+        $user = factory(User::class)->create([
+            'name' => 'foo',
+        ]);
+
+        $this->schema = /** @lang GraphQL */'
+        type Query {
+            user(id: ID @eq): User
+                @can(ability: "view", find: "INVALID_KEY")
+                @first
+        }
+
+        type User {
+            id: ID!
+            name: String!
+        }
+        ';
+
+        $this->expectException(DefinitionException::class);
+        $this->graphQL(/** @lang GraphQL */ "
+        {
+            user(id: {$user->getKey()}) {
+                name
+            }
+        }");
+    }
+
+    public function testThrowsIfNullFindValue()
+    {
+        $this->be(
+            new User([
+                'name' => UserPolicy::ADMIN,
+            ])
+        );
+
+        $user = factory(User::class)->create([
+            'name' => 'foo',
+        ]);
+
+        $this->schema = /** @lang GraphQL */
+            '
+        type Query {
+            user(id: ID @eq, queriedUserId: ID): User
+                @can(ability: "view", find: "queriedUserId")
+                @first
+        }
+
+        type User {
+            id: ID!
+            name: String!
+        }
+        ';
+
+        $this->expectException(DefinitionException::class);
+        $this->graphQL(/** @lang GraphQL */ "
+        {
+            user(id: {$user->getKey()}, queriedUserId: null) {
+                name
+            }
+        }");
+    }
+
+    public function testNestedQueriesForSpecificModel(): void
+    {
+        $user = factory(User::class)->create([
+            'name' => 'foo',
+        ]);
+        $this->be($user);
+
+        $this->schema = /** @lang GraphQL */
+            '
+        type Query {
+            user(input: FindUserInput): User
+                @can(ability: "view", find: "input.id")
+                @first
+        }
+
+        type User {
+            id: ID!
+            name: String!
+        }
+        
+        input FindUserInput {
+          id: ID
+        }
+        ';
+
+        $this->graphQL(/** @lang GraphQL */ "
+        {
+            user(input: {
+              id: {$user->getKey()}
+            }) {
+                name
+            }
+        }
+        ")->assertJson([
+            'data' => [
+                'user' => [
+                    'name' => 'foo',
+                ],
+            ],
+        ]);
+    }
+
     public function testThrowsIfNotAuthorized(): void
     {
         $this->be(