Alerting: Metric to count imported from Prometheus rules (#100847)

pkg/services/ngalert/api/api_convert_prometheus.go

@@ -457,9 +457,9 @@ func grafanaRuleGroupToPrometheus(group string, rules []models.AlertRule) (apimo
 	}
 
 	for i, rule := range rules {
-		promDefinition := rule.PrometheusRuleDefinition()
-		if promDefinition == "" {
-			return apimodels.PrometheusRuleGroup{}, fmt.Errorf("failed to get the Prometheus definition of the rule with UID %s", rule.UID)
+		promDefinition, err := rule.PrometheusRuleDefinition()
+		if err != nil {
+			return apimodels.PrometheusRuleGroup{}, fmt.Errorf("failed to get the Prometheus definition of the rule with UID %s: %w", rule.UID, err)
 		}
 		var r apimodels.PrometheusRule
 		if err := yaml.Unmarshal([]byte(promDefinition), &r); err != nil {

pkg/services/ngalert/api/api_convert_prometheus_test.go

@@ -115,7 +115,10 @@ func TestRouteConvertPrometheusPostRuleGroup(t *testing.T) {
 		require.Equal(t, fmt.Sprintf("[%s] %s", simpleGroup.Name, simpleGroup.Rules[0].Alert), remaining[0].Title)
 		promRuleYAML, err := yaml.Marshal(simpleGroup.Rules[0])
 		require.NoError(t, err)
-		require.Equal(t, string(promRuleYAML), remaining[0].PrometheusRuleDefinition())
+
+		promDefinition, err := remaining[0].PrometheusRuleDefinition()
+		require.NoError(t, err)
+		require.Equal(t, string(promRuleYAML), promDefinition)
 	})
 
 	t.Run("should fail to replace a provisioned rule group", func(t *testing.T) {