fix: Cache object templates at AbstractMISP level

Related #468 and  #471

pymisp/abstract.py

@@ -88,6 +88,12 @@ if sys.version_info >= (3, 6):
         with (resources_path / 'describeTypes.json').open() as f:
             dt = json.load(f)
         return dt['result']
+
+    def load_template(path):
+        with open(path) as f:
+            t = json.load(f)
+        return t
+
 else:
     import os
     if (3, 0) <= sys.version_info < (3, 6):
@@ -104,10 +110,19 @@ else:
                 t = json.load(f)
         return t['result']
 
+    def load_template(path):
+        with open(path, 'rb') as f:
+            if OLD_PY3:
+                t = json.loads(f.read().decode())
+            else:
+                t = json.load(f)
+        return t
+
 
 class AbstractMISP(MutableMapping):
 
     __describe_types = cache_describe_types()
+    __object_templates = {}
 
     def __init__(self, **kwargs):
         """Abstract class for all the MISP objects"""
@@ -133,6 +148,11 @@ class AbstractMISP(MutableMapping):
     def describe_types(self):
         return self.__describe_types
 
+    def get_template_definition(self, template_path):
+        if template_path not in self.__object_templates:
+            self.__object_templates[template_path] = load_template(template_path)
+        return self.__object_templates[template_path]
+
     @property
     def properties(self):
         """All the class public properties that will be dumped in the dictionary, and the JSON export.

pymisp/mispevent.py

@@ -111,8 +111,8 @@ class MISPAttribute(AbstractMISP):
         super(MISPAttribute, self).__init__()
         if not describe_types:
             describe_types = self.describe_types
-        self.__categories = frozenset(describe_types['categories'])
-        self._types = frozenset(describe_types['types'])
+        self.__categories = describe_types['categories']
+        self._types = describe_types['types']
         self.__category_type_mapping = describe_types['category_type_mappings']
         self.__sane_default = describe_types['sane_defaults']
         self.__strict = strict
@@ -438,7 +438,7 @@ class MISPEvent(AbstractMISP):
         else:
             self._describe_types = self.describe_types
 
-        self._types = frozenset(self._describe_types['types'])
+        self._types = self._describe_types['types']
         self.Attribute = []
         self.Object = []
         self.RelatedEvent = []
@@ -1195,11 +1195,7 @@ class MISPObject(AbstractMISP):
     def _load_template_path(self, template_path):
         if not os.path.exists(template_path):
             return False
-        with open(template_path, 'rb') as f:
-            if OLD_PY3:
-                self._definition = json.loads(f.read().decode())
-            else:
-                self._definition = json.load(f)
+        self._definition = self.get_template_definition(template_path)
         setattr(self, 'meta-category', self._definition['meta-category'])
         self.template_uuid = self._definition['uuid']
         self.description = self._definition['description']