feat(alerts): Add alert type filter backend (#83784)

Supports a `alertType` query parameter (as a list) to filter down the
alerts

Supports

- `rule` (classic issue alert)
- `alert_rule` (metric alert)
- `uptime` (uptime monitor)
- `monitor` (cron monitor)

---------

Co-authored-by: getsantry[bot] <66042841+getsantry[bot]@users.noreply.github.com>

src/sentry/incidents/endpoints/organization_alert_rule_index.py

@@ -322,13 +322,20 @@ def get(self, request: Request, organization) -> Response:
                 ),
             )
 
-        intermediaries = [
-            CombinedQuerysetIntermediary(alert_rules, sort_key),
-            CombinedQuerysetIntermediary(issue_rules, rule_sort_key),
-            CombinedQuerysetIntermediary(uptime_rules, sort_key),
-        ]
+        type_filter = request.GET.getlist("alertType", [])
+
+        def has_type(type: str) -> bool:
+            return not type_filter or type in type_filter
+
+        intermediaries: list[CombinedQuerysetIntermediary] = []
 
-        if features.has("organizations:insights-crons", organization):
+        if has_type("alert_rule"):
+            intermediaries.append(CombinedQuerysetIntermediary(alert_rules, sort_key))
+        if has_type("rule"):
+            intermediaries.append(CombinedQuerysetIntermediary(issue_rules, rule_sort_key))
+        if has_type("uptime"):
+            intermediaries.append(CombinedQuerysetIntermediary(uptime_rules, sort_key))
+        if has_type("monitor") and features.has("organizations:insights-crons", organization):
             intermediaries.append(CombinedQuerysetIntermediary(crons_rules, sort_key))
 
         response = self.paginate(

tests/sentry/incidents/endpoints/test_organization_combined_rule_index_endpoint.py

@@ -1309,3 +1309,65 @@ def test_dataset_filter(self):
             # without performance-view, we should only see events rules
             res = self.get_success_response(self.organization.slug)
             self.assert_alert_rule_serialized(events_rule, res.data[0], skip_dates=True)
+
+    def test_alert_type_filter(self):
+        # Setup one of each type of alert rule
+        metric_rule = self.create_alert_rule()
+        issue_rule = self.create_issue_alert_rule(
+            data={
+                "project": self.project,
+                "name": "Issue Rule Test",
+                "conditions": [],
+                "actions": [],
+                "actionMatch": "all",
+                "date_added": before_now(minutes=4),
+            }
+        )
+        uptime_rule = self.create_project_uptime_subscription(project=self.project)
+        cron_rule = self.create_monitor(project=self.project)
+
+        features = [
+            "organizations:incidents",
+            "organizations:performance-view",
+            "organizations:insights-crons",
+        ]
+
+        # Everything comes back without the query parameter
+        with self.feature(features):
+            request_data = {"per_page": "10", "project": [self.project.id]}
+            response = self.client.get(
+                path=self.combined_rules_url,
+                data=request_data,
+                content_type="application/json",
+            )
+            assert response.status_code == 200, response.content
+            assert {r["id"] for r in response.data} == {
+                str(metric_rule.id),
+                str(issue_rule.id),
+                str(uptime_rule.id),
+                str(cron_rule.guid),
+            }
+
+        test_cases: list[tuple[list[str], set[str]]] = [
+            (["rule"], {str(issue_rule.id)}),
+            (["alert_rule"], {str(metric_rule.id)}),
+            (["monitor"], {str(cron_rule.guid)}),
+            (["uptime"], {str(uptime_rule.id)}),
+            (["rule", "alert_rule"], {str(issue_rule.id), str(metric_rule.id)}),
+            (["uptime", "monitor"], {str(uptime_rule.id), str(cron_rule.guid)}),
+        ]
+
+        for alert_type, expected_ids in test_cases:
+            with self.feature(features):
+                request_data = {
+                    "per_page": "10",
+                    "project": [self.project.id],
+                    "alertType": alert_type,
+                }
+                response = self.client.get(
+                    path=self.combined_rules_url,
+                    data=request_data,
+                    content_type="application/json",
+                )
+                assert response.status_code == 200, response.content
+                assert {r["id"] for r in response.data} == expected_ids