Minor fixes + test fixes

Author: Artem Batalov

core/monitoring/monitoring.py

@@ -4,7 +4,7 @@
 from core.logging.logger_constants import KEY_NAME
 from core.logging.logger_utils import log
 
-from prometheus_client import Counter, Histogram
+from prometheus_client import Counter, Histogram, REGISTRY
 
 
 def _filter_monitoring_msg(msg):
@@ -34,15 +34,23 @@ class Monitoring:
     HISTOGRAM = "histogram"
     DEFAULT_ENABLED = True
     DEFAULT_DISABLED_METRICS = []
-    _monitoring_items = {
-        COUNTER: {},
-        HISTOGRAM: {}
-    }
 
     def __init__(self):
         self._enabled = self.DEFAULT_ENABLED
         self.disabled_metrics = self.DEFAULT_DISABLED_METRICS.copy()
         self.buckets = Histogram.DEFAULT_BUCKETS
+        self._monitoring_items = {
+            self.COUNTER: {},
+            self.HISTOGRAM: {}
+        }
+        self._clean_registry()
+
+    @staticmethod
+    def _clean_registry():
+        """При создании нового инстанса мониторинга удаляем все созданные коллекторы"""
+        collectors = list(REGISTRY._collector_to_names.keys())
+        for collector in collectors:
+            REGISTRY.unregister(collector)
 
     def check_enabled(self, name: str):
         metric_disabled = next((True for m in self.disabled_metrics if re.fullmatch(m, name)), False)
@@ -287,7 +295,7 @@ def wrap(*args, **kwargs):
         return decor_
 
     def set_instance(self, cls):
-        if not isinstance(self.instance, cls):
+        if type(self.instance) != type(cls):
             self.instance = cls()
 
     def __getattr__(self, item):

tests/core_tests/monitoring_test/test_monitoring.py

@@ -13,10 +13,6 @@ def setUp(self):
         self.logger.exception = PicklableMock()
         self.config = PicklableMock()
         self.mock_rep = PicklableMock()
-        Monitoring._monitoring_items = {
-            Monitoring.COUNTER: {},
-            Monitoring.HISTOGRAM: {}
-        }
         self.monitoring = Monitoring()
         self.monitoring.apply_config({})
 
@@ -75,19 +71,28 @@ def test_monitoring_init(self):
         from core.monitoring.monitoring import monitoring
 
         class MyCustomMonitoring(Monitoring):
-            pass
+            def got_histogram(self, name, description=None):
+                def decorator(function):
+                    def wrapper(*args, **kwargs):
+                        result = function(*args, **kwargs) + " " + name
+                        return result
+                    return wrapper
+                return decorator
 
         class SomeClass:
             @monitoring.got_histogram("test_histogram")
             def some_method(self):
                 return "test"
 
+        obj = SomeClass()
+
         monitoring.set_instance(MyCustomMonitoring)
         self.assertIsInstance(monitoring.instance, MyCustomMonitoring)
+
+        self.assertEqual(obj.some_method(), "test test_histogram")
+
         monitoring.set_instance(Monitoring)
         self.assertIsInstance(monitoring.instance, Monitoring)
-        obj = SomeClass()
-        self.assertEqual(obj.some_method(), "test")
+
         self.assertEqual(obj.some_method(), "test")
-        self.assertIn('test_histogram', Monitoring._monitoring_items[Monitoring.HISTOGRAM].keys())
-        self.assertIn('test_histogram', MyCustomMonitoring._monitoring_items[Monitoring.HISTOGRAM].keys())
+        self.assertIn('test_histogram', monitoring._monitoring_items[Monitoring.HISTOGRAM].keys())