Alerting: Add endpoint for querying state history (#62166)

* Define endpoint and generate

* Wire up and register endpoint

* Cleanup, define authorization

* Forgot the leading slash

* Wire up query and SignedInUser

* Wire up timerange query params

* Add todo for label queries

* Drop comment

* Update path to rules subtree

pkg/services/ngalert/api/generated_base_api_history.go

@@ -0,0 +1,40 @@
+/*Package api contains base API implementation of unified alerting
+ *
+ *Generated by: Swagger Codegen (https://github.com/swagger-api/swagger-codegen.git)
+ *
+ *Do not manually edit these files, please find ngalert/api/swagger-codegen/ for commands on how to generate them.
+ */
+package api
+
+import (
+	"net/http"
+
+	"github.com/grafana/grafana/pkg/api/response"
+	"github.com/grafana/grafana/pkg/api/routing"
+	"github.com/grafana/grafana/pkg/middleware"
+	contextmodel "github.com/grafana/grafana/pkg/services/contexthandler/model"
+	"github.com/grafana/grafana/pkg/services/ngalert/metrics"
+)
+
+type HistoryApi interface {
+	RouteGetStateHistory(*contextmodel.ReqContext) response.Response
+}
+
+func (f *HistoryApiHandler) RouteGetStateHistory(ctx *contextmodel.ReqContext) response.Response {
+	return f.handleRouteGetStateHistory(ctx)
+}
+
+func (api *API) RegisterHistoryApiEndpoints(srv HistoryApi, m *metrics.API) {
+	api.RouteRegister.Group("", func(group routing.RouteRegister) {
+		group.Get(
+			toMacaronPath("/api/v1/rules/history"),
+			api.authorize(http.MethodGet, "/api/v1/rules/history"),
+			metrics.Instrument(
+				http.MethodGet,
+				"/api/v1/rules/history",
+				srv.RouteGetStateHistory,
+				m,
+			),
+		)
+	}, middleware.ReqSignedIn)
+}