Chore: Refactor quota service (#58643)

Chore: Refactor quota service (#57586)

* Chore: refactore quota service

* Apply suggestions from code review

pkg/tests/api/alerting/testing.go

@@ -16,6 +16,7 @@ import (
 
 	apimodels "github.com/grafana/grafana/pkg/services/ngalert/api/tooling/definitions"
 	ngmodels "github.com/grafana/grafana/pkg/services/ngalert/models"
+	"github.com/grafana/grafana/pkg/services/quota"
 	"github.com/grafana/grafana/pkg/util"
 )
 
@@ -202,6 +203,60 @@ func (a apiClient) CreateFolder(t *testing.T, uID string, title string) {
 	a.ReloadCachedPermissions(t)
 }
 
+func (a apiClient) GetOrgQuotaLimits(t *testing.T, orgID int64) (int64, int64) {
+	t.Helper()
+
+	u := fmt.Sprintf("%s/api/orgs/%d/quotas", a.url, orgID)
+	// nolint:gosec
+	resp, err := http.Get(u)
+	require.NoError(t, err)
+	defer func() {
+		_ = resp.Body.Close()
+	}()
+	b, err := io.ReadAll(resp.Body)
+	require.NoError(t, err)
+	require.Equal(t, http.StatusOK, resp.StatusCode)
+
+	results := []quota.QuotaDTO{}
+	require.NoError(t, json.Unmarshal(b, &results))
+
+	var limit int64 = 0
+	var used int64 = 0
+	for _, q := range results {
+		if q.Target != string(ngmodels.QuotaTargetSrv) {
+			continue
+		}
+		limit = q.Limit
+		used = q.Used
+	}
+	return limit, used
+}
+
+func (a apiClient) UpdateAlertRuleOrgQuota(t *testing.T, orgID int64, limit int64) {
+	t.Helper()
+	buf := bytes.Buffer{}
+	enc := json.NewEncoder(&buf)
+	err := enc.Encode(&quota.UpdateQuotaCmd{
+		Target: "alert_rule",
+		Limit:  limit,
+		OrgID:  orgID,
+	})
+	require.NoError(t, err)
+
+	u := fmt.Sprintf("%s/api/orgs/%d/quotas/alert_rule", a.url, orgID)
+	// nolint:gosec
+	client := &http.Client{}
+	req, err := http.NewRequest(http.MethodPut, u, &buf)
+	require.NoError(t, err)
+	req.Header.Add("Content-Type", "application/json")
+	resp, err := client.Do(req)
+	require.NoError(t, err)
+	defer func() {
+		_ = resp.Body.Close()
+	}()
+	assert.Equal(t, http.StatusOK, resp.StatusCode)
+}
+
 func (a apiClient) PostRulesGroup(t *testing.T, folder string, group *apimodels.PostableRuleGroupConfig) (int, string) {
 	t.Helper()
 	buf := bytes.Buffer{}