draft of rate limiter

src/sentry/issues/occurrence_consumer.py

@@ -18,6 +18,7 @@
 from sentry_sdk.tracing import NoOpSpan, Span, Transaction
 
 from sentry import features, nodestore
+from sentry import ratelimits as ratelimiter
 from sentry.event_manager import GroupInfo
 from sentry.eventstore.models import Event
 from sentry.issues.grouptype import get_group_type_by_type_id
@@ -319,6 +320,21 @@ def process_occurrence_message(
         txn.set_tag("result", "dropped_feature_disabled")
         return None
 
+    # Rate limit based on project and fingerprint
+    rate_limit_key = f"occurrence_rate_limit:{occurrence_data['fingerprint']}"
+    if ratelimiter.is_limited(
+        rate_limit_key,
+        limit=10,
+        window=60,  # 10 occurrences per minute
+    ):
+        metrics.incr(
+            "occurrence_ingest.dropped_rate_limited",
+            sample_rate=1.0,
+            tags=metric_tags,
+        )
+        txn.set_tag("result", "dropped_rate_limited")
+        return None
+
     if "event_data" in kwargs and is_buffered_spans:
         return create_event_and_issue_occurrence(kwargs["occurrence_data"], kwargs["event_data"])
     elif "event_data" in kwargs:

tests/sentry/issues/test_occurrence_consumer.py

@@ -6,6 +6,7 @@
 from datetime import timezone
 from typing import Any
 from unittest import mock
+from unittest.mock import patch
 
 import pytest
 from django.core.cache import cache
@@ -243,6 +244,16 @@ def test_new_group_with_invalid_user_assignee(self) -> None:
         with pytest.raises(GroupAssignee.DoesNotExist):
             GroupAssignee.objects.get(group=group)
 
+    @patch(
+        "sentry.issues.occurrence_consumer.ratelimiter.backend.is_limited",
+        return_value=True,
+    )
+    def test_rate_limit(self, is_limited) -> None:
+        message = get_test_message(self.project.id)
+        with self.feature("organizations:profile-file-io-main-thread-ingest"):
+            result = _process_message(message)
+        assert result is None
+
 
 class IssueOccurrenceLookupEventIdTest(IssueOccurrenceTestBase):
     def test_lookup_event_doesnt_exist(self) -> None: