Improved mokey event fetching and added unit tests

monkey/monkey_island/cc/services/zero_trust/monkey_findings/monkey_zt_details_service.py

@@ -4,9 +4,10 @@ from bson import ObjectId
 
 from monkey_island.cc.models.zero_trust.monkey_finding_details import MonkeyFindingDetails
 
+
 # How many events of a single finding to return to UI.
-# 50 will return 50 latest and 50 oldest events from a finding
+# 100 will return 50 latest and 50 oldest events from a finding
-EVENT_FETCH_CNT = 50
+MAX_EVENT_FETCH_CNT = 100
 
 
 class MonkeyZTDetailsService:
@@ -14,25 +15,29 @@ class MonkeyZTDetailsService:
     @staticmethod
     def fetch_details_for_display(finding_id: ObjectId) -> dict:
         pipeline = [{'$match': {'_id': finding_id}},
-                    {'$addFields': {'oldest_events': {'$slice': ['$events', EVENT_FETCH_CNT]},
+                    {'$addFields': {'oldest_events': {'$slice': ['$events', int(MAX_EVENT_FETCH_CNT / 2)]},
-                                    'latest_events': {'$slice': ['$events', -1 * EVENT_FETCH_CNT]},
+                                    'latest_events': {'$slice': ['$events', int(-1 * MAX_EVENT_FETCH_CNT / 2)]},
                                     'event_count': {'$size': '$events'}}},
-                    {'$unset': ['events', 'checked_subnet_pairs']}]
+                    {'$unset': ['events']}]
         details = list(MonkeyFindingDetails.objects.aggregate(*pipeline))
         if details:
             details = details[0]
-            details['latest_events'] = MonkeyZTDetailsService._get_events_without_overlap(details['event_count'],
+            details['latest_events'] = MonkeyZTDetailsService._remove_redundant_events(details['event_count'],
-                                                                                          details['latest_events'])
+                                                                                       details['latest_events'])
             return details
         else:
             return {}
 
     @staticmethod
-    def _get_events_without_overlap(event_count: int, events: List[object]) -> List[object]:
+    def _remove_redundant_events(fetched_event_count: int, latest_events: List[object]) -> List[object]:
-        overlap_count = event_count - EVENT_FETCH_CNT
+        overlap_count = fetched_event_count - int(MAX_EVENT_FETCH_CNT/2)
-        if overlap_count >= EVENT_FETCH_CNT:
+        # None of 'latest_events' are in 'oldest_events'
-            return events
+        if overlap_count >= MAX_EVENT_FETCH_CNT:
+            return latest_events
+        # All 'latest_events' are already in 'oldest_events'
         elif overlap_count <= 0:
             return []
+        # Some of 'latest_events' are already in 'oldest_events'.
+        # Return only those that are not
         else:
-            return events[-1 * overlap_count:]
+            return latest_events[-1 * overlap_count:]

monkey/monkey_island/cc/services/zero_trust/monkey_findings/test_monkey_zt_details_service.py

@@ -0,0 +1,31 @@
+from monkey_island.cc.services.zero_trust.monkey_findings import monkey_zt_details_service
+from monkey_island.cc.services.zero_trust.monkey_findings.monkey_zt_details_service import MonkeyZTDetailsService
+
+
+def test__remove_redundant_events(monkeypatch):
+    monkeypatch.setattr(monkey_zt_details_service, 'MAX_EVENT_FETCH_CNT', 6)
+
+    # No events are redundant, 8 events in the database, but we display only 6 (3 latest and 3 oldest)
+    latest_events = ['6', '7', '8']
+    _do_redundant_event_removal_test(latest_events, 8, ['6', '7', '8'])
+
+    # All latest events are redundant (only 3 events in db and we fetched them twice)
+    latest_events = ['1', '2', '3']
+    _do_redundant_event_removal_test(latest_events, 3, [])
+
+    # Some latest events are redundant (5 events in db and we fetched 3 oldest and 3 latest)
+    latest_events = ['3', '4', '5']
+    _do_redundant_event_removal_test(latest_events, 5, ['4', '5'])
+
+    # None of the events are redundant (6 events in db and we fetched 3 oldest and 3 latest)
+    latest_events = ['4', '5', '6']
+    _do_redundant_event_removal_test(latest_events, 6, ['4', '5', '6'])
+
+    # No events fetched, should return empty array also
+    latest_events = []
+    _do_redundant_event_removal_test(latest_events, 0, [])
+
+
+def _do_redundant_event_removal_test(input_list, fetched_event_cnt, expected_output):
+    output_events = MonkeyZTDetailsService._remove_redundant_events(fetched_event_cnt, input_list)
+    assert output_events == expected_output