diff --git a/lockable/lockable.py b/lockable/lockable.py
index 5ced918..680dd0f 100644
--- a/lockable/lockable.py
+++ b/lockable/lockable.py
@@ -56,6 +56,7 @@ class Lockable:
     """
     def __init__(self, hostname=socket.gethostname(),
                  resource_list_file=None,
+                 resource_list=None,
                  lock_folder=tempfile.gettempdir()):
         self._allocations = dict()
         self.logger = logging.getLogger('lockable.Lockable')
@@ -63,18 +64,29 @@ def __init__(self, hostname=socket.gethostname(),
         self._hostname = hostname
         self._lock_folder = lock_folder
         self._resource_list = None
-        if resource_list_file:
-            self.load_resources_list(resource_list_file)
+        assert not (isinstance(resource_list, list) and
+                    resource_list_file), 'only one of resource_list or ' \
+                                         'resource_list_file is accepted, not both'
+        if isinstance(resource_list_file, str):
+            self.load_resources_list_file(resource_list_file)
+        elif isinstance(resource_list, list):
+            self.load_resources_list(resource_list)
         else:
-            self.logger.warning('resource_list_file is not configured')
+            self.logger.warning('resource_list_file or resource_list is not configured')
 
-    def load_resources_list(self, filename: str):
+    def load_resources_list_file(self, filename: str):
+        """ Load resources list file"""
+        self.load_resources_list(self._read_resources_list(filename))
+        self.logger.warning('Use resources from %s file', filename)
+
+    def load_resources_list(self, resources_list: list):
         """ Load resources list """
-        self._resource_list = self._read_resources_list(filename)
-        self.logger.debug('Resources: ')
+        assert isinstance(resources_list, list), 'resources_list is not an list'
+        self._resource_list = resources_list
+        self.logger.debug('Resources loaded: ')
         for resource in self._resource_list:
             self.logger.debug(json.dumps(resource))
-        self.logger.warning('Use resources from %s file', filename)
+
 
     @staticmethod
     def _read_resources_list(filename):
diff --git a/tests/test_Lockable.py b/tests/test_Lockable.py
index 85f57a9..664243a 100644
--- a/tests/test_Lockable.py
+++ b/tests/test_Lockable.py
@@ -12,10 +12,7 @@
 def create_lockable(data=[{"id": 1, "hostname": "myhost", "online": True}], lock_folder=None):
     with TemporaryDirectory() as tmpdirname:
         lock_folder = lock_folder or tmpdirname
-        list_file = os.path.join(tmpdirname, 'test.json')
-        with open(list_file, 'w') as fp:
-            fp.write(json.dumps(data))
-        yield Lockable(hostname='myhost', resource_list_file=list_file, lock_folder=lock_folder)
+        yield Lockable(hostname='myhost', resource_list=data, lock_folder=lock_folder)
 
 
 class LockableTests(TestCase):
@@ -32,6 +29,11 @@ def test_constructor(self):
                 fp.write('[]')
             Lockable(hostname='myhost', resource_list_file=list_file, lock_folder=tmpdirname)
 
+    def test_invalid_constructor(self):
+        with self.assertRaises(AssertionError):
+            Lockable(hostname='myhost', resource_list_file='asdf',
+                     resource_list=[], lock_folder='.')
+
     def test_lock_require_resources_json_loaded(self):
         lockable = Lockable()
         with self.assertRaises(AssertionError) as error: