feat: unlimited alerts for paid plans (#26338)

posthog/api/alert.py

@@ -18,6 +18,7 @@ from posthog.api.insight import InsightBasicSerializer
 
 from posthog.utils import relative_date_parse
 from zoneinfo import ZoneInfo
+from posthog.constants import AvailableFeature
 
 
 class ThresholdSerializer(serializers.ModelSerializer):
@@ -246,13 +247,39 @@ class AlertSerializer(serializers.ModelSerializer):
         if attrs.get("insight") and attrs["insight"].team.id != self.context["team_id"]:
             raise ValidationError({"insight": ["This insight does not belong to your team."]})
 
-        if attrs.get("enabled") is not False and (
-            AlertConfiguration.objects.filter(team_id=self.context["team_id"], enabled=True).count()
-            >= AlertConfiguration.ALERTS_PER_TEAM
-        ):
-            raise ValidationError(
-                {"alert": [f"Your team has reached the limit of {AlertConfiguration.ALERTS_PER_TEAM} enabled alerts."]}
-            )
+        # only validate alert count when creating a new alert
+        if self.context["request"].method != "POST":
+            return attrs
+
+        user_org = self.context["request"].user.organization
+
+        has_alerts_feature = user_org.is_feature_available(AvailableFeature.ALERTS)
+
+        allowed_alerts_count = next(
+            (
+                feature.get("limit")
+                for feature in user_org.available_product_features or []
+                if feature.get("key") == AvailableFeature.ALERTS
+            ),
+            None,
+        )
+
+        existing_alerts_count = AlertConfiguration.objects.filter(team_id=self.context["team_id"]).count()
+
+        if has_alerts_feature:
+            # If allowed_alerts_count is None then the user is allowed unlimited alerts
+            if allowed_alerts_count is not None:
+                # Check current count against allowed limit
+                if existing_alerts_count >= allowed_alerts_count:
+                    raise ValidationError(
+                        {"alert": [f"Your team has reached the limit of {allowed_alerts_count} alerts on your plan."]}
+                    )
+        else:
+            # If the org doesn't have alerts feature, limit to that on free tier
+            if existing_alerts_count >= AlertConfiguration.ALERTS_ALLOWED_ON_FREE_TIER:
+                raise ValidationError(
+                    {"alert": [f"Your plan is limited to {AlertConfiguration.ALERTS_ALLOWED_ON_FREE_TIER} alerts"]}
+                )
 
         return attrs
 

posthog/api/test/test_alert.py

@@ -130,7 +130,7 @@ class TestAlert(APIBaseTest, QueryMatchingTest):
         assert len(list_for_another_insight.json()["results"]) == 0
 
     def test_alert_limit(self) -> None:
-        with mock.patch("posthog.api.alert.AlertConfiguration.ALERTS_PER_TEAM") as alert_limit:
+        with mock.patch("posthog.api.alert.AlertConfiguration.ALERTS_ALLOWED_ON_FREE_TIER") as alert_limit:
             alert_limit.__get__ = mock.Mock(return_value=1)
 
             creation_request = {

posthog/models/alert.py

@@ -68,7 +68,7 @@ class Threshold(CreatedMetaFields, UUIDModel):
 
 
 class AlertConfiguration(CreatedMetaFields, UUIDModel):
-    ALERTS_PER_TEAM = 5
+    ALERTS_ALLOWED_ON_FREE_TIER = 2
 
     team = models.ForeignKey("Team", on_delete=models.CASCADE)
     insight = models.ForeignKey("posthog.Insight", on_delete=models.CASCADE)