new: Method to check event existence

pymisp/api.py

@@ -307,6 +307,15 @@ class PyMISP:
         e.load(event_r)
         return e
 
+    def event_exists(self, event: Union[MISPEvent, int, str, UUID]) -> bool:
+        """Fast check if event exists.
+
+        :param event: Event to check
+        """
+        event_id = get_uuid_or_id_from_abstract_misp(event)
+        r = self._prepare_request('HEAD', f'events/view/{event_id}')
+        return self._check_head_response(r)
+
     def add_event(self, event: MISPEvent, pythonify: bool = False) -> Union[Dict, MISPEvent]:
         """Add a new event on a MISP instance
 
@@ -2965,6 +2974,14 @@ class PyMISP:
             return r
         # Else: an exception was raised anyway
 
+    def _check_head_response(self, response: requests.Response) -> bool:
+        if response.status_code == 200:
+            return True
+        elif response.status_code == 404:
+            return False
+        else:
+            raise MISPServerError(f'Error code {response.status_code} for HEAD request')
+
     def _check_response(self, response: requests.Response, lenient_response_type: bool = False, expect_json: bool = False) -> Union[Dict, str]:
         """Check if the response from the server is not an unexpected error"""
         if response.status_code >= 500:

tests/testlive_comprehensive.py

@@ -713,7 +713,9 @@ class TestComprehensive(unittest.TestCase):
         second.add_attribute('ip-src', '8.8.8.8')
         # second has two attributes: text and ip-src
         try:
+            self.assertFalse(self.user_misp_connector.event_exists(first))
             first = self.user_misp_connector.add_event(first)
+            self.assertTrue(self.user_misp_connector.event_exists(first))
             second = self.user_misp_connector.add_event(second)
             timeframe = [first.timestamp.timestamp() - 5, first.timestamp.timestamp() + 5]
             # Search event we just created in multiple ways. Make sure it doesn't catch it when it shouldn't