add test for null output plugin

Author: cw-Guo

apis/fluentd/v1alpha1/tests/expected/fluentd-cluster-cfg-output-null.cfg

@@ -0,0 +1,30 @@
+<source>
+  @type  forward
+  bind  0.0.0.0
+  port  24224
+</source>
+<match **>
+  @id  main
+  @type  label_router
+  <route>
+    @label  @a2170d34e9940ec56d328100e375c43e
+    <match>
+      namespaces  default,kube-system
+    </match>
+  </route>
+</match>
+<label @a2170d34e9940ec56d328100e375c43e>
+  <filter **>
+    @id  ClusterFluentdConfig-cluster-fluentd-config::cluster::clusterfilter::fluentd-filter-0
+    @type  record_transformer
+    enable_ruby  true
+    <record>
+      kubernetes_ns  ${record["kubernetes"]["namespace_name"]}
+    </record>
+  </filter>
+  <match **>
+    @id  ClusterFluentdConfig-cluster-fluentd-config::cluster::clusteroutput::fluentd-output-null-0
+    @type  null
+    never_flush  false
+  </match>
+</label>

apis/fluentd/v1alpha1/tests/helper_test.go

@@ -381,6 +381,31 @@ func Test_ClusterCfgOutput2Datadog(t *testing.T) {
 	}
 }
 
+func Test_ClusterCfgOutput2Null(t *testing.T) {
+	g := NewGomegaWithT(t)
+	sl := plugins.NewSecretLoader(nil, Fluentd.Namespace, logr.Logger{})
+
+	psr := fluentdv1alpha1.NewGlobalPluginResources("main")
+	psr.CombineGlobalInputsPlugins(sl, Fluentd.Spec.GlobalInputs)
+
+	clustercfgRouter, err := psr.BuildCfgRouter(&FluentdClusterFluentdConfig1)
+	g.Expect(err).NotTo(HaveOccurred())
+	clusterFilters := []fluentdv1alpha1.ClusterFilter{FluentdClusterFilter1}
+	clusterOutputs := []fluentdv1alpha1.ClusterOutput{FluentdClusterOutput2Null}
+	clustercfgResources, _ := psr.PatchAndFilterClusterLevelResources(sl, FluentdClusterFluentdConfig1.GetCfgId(), []fluentdv1alpha1.ClusterInput{}, clusterFilters, clusterOutputs)
+	err = psr.WithCfgResources(*clustercfgRouter.Label, clustercfgResources)
+	g.Expect(err).NotTo(HaveOccurred())
+
+	i := 0
+	for i < maxRuntimes {
+		config, errs := psr.RenderMainConfig(false)
+		g.Expect(errs).NotTo(HaveOccurred())
+		g.Expect(strings.TrimSpace(string(getExpectedCfg("./expected/fluentd-cluster-cfg-output-null.cfg")))).To(Equal(config))
+
+		i++
+	}
+
+}
 func Test_MixedCfgCopy1(t *testing.T) {
 	g := NewGomegaWithT(t)
 	sl := NewSecretLoader(logr.Logger{}, lokiHttpCredentials, lokiTenantName)

apis/fluentd/v1alpha1/tests/tools.go

@@ -860,6 +860,20 @@ spec:
       port: 443
       ddSource: kubernetes
       ddSourcecategory: kubernetes
+`
+	FluentdClusterOutput2Null    fluentdv1alpha1.ClusterOutput
+	FluentdClusterOutput2NullRaw = `
+apiVersion: fluentd.fluent.io/v1alpha1
+kind: ClusterOutput
+metadata:
+  name: fluentd-output-null
+  namespace: fluent
+  labels:
+    output.fluentd.fluent.io/enabled: "true"
+spec: 
+  outputs: 
+  - nullPlugin:
+      neverFlush: false
 `
 	FluentdClusterOutputCopy2StdoutAndLoki    fluentdv1alpha1.ClusterOutput
 	FluentdClusterOutputCopy2StdoutAndLokiRaw = `
@@ -1052,6 +1066,7 @@ func init() {
 			ParseIntoObject(FluentdClusterOutputCustomRaw, &FluentdClusterOutputCustom)
 			ParseIntoObject(FluentdClusterOutput2CloudWatchRaw, &FluentdClusterOutput2CloudWatch)
 			ParseIntoObject(FluentdClusterOutput2DatadogRaw, &FluentdClusterOutput2Datadog)
+			ParseIntoObject(FluentdClusterOutput2NullRaw, &FluentdClusterOutput2Null)
 			ParseIntoObject(FluentdClusterOutputCopy2StdoutAndLokiRaw, &FluentdClusterOutputCopy2StdoutAndLoki)
 			ParseIntoObject(FluentdOutputMixedCopy1Raw, &FluentdOutputMixedCopy1)
 			ParseIntoObject(FluentdOutputMixedCopy2Raw, &FluentdOutputMixedCopy2)