Define a helper method pkg/controller.FilterRunRef

This will be useful to external Custom Task controllers to filter out
update notifications for Runs of irrelevant types.

pkg/controller/filter.go

@@ -0,0 +1,52 @@
+/*
+Copyright 2020 The Tekton Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package controller provides helper methods for external controllers for
+// Custom Task types.
+package controller
+
+import (
+ "github.com/tektoncd/pipeline/pkg/apis/pipeline/v1alpha1"
+)
+
+// FilterRunRef returns a filter that can be passed to a Run Informer, which
+// filters out Runs for apiVersion and kinds that a controller doesn't care
+// about.
+//
+// For example, a controller impl that wants to be notified of updates to Runs
+// which reference a Task with apiVersion "example.dev/v0" and kind "Example":
+//
+// runinformer.Get(ctx).Informer().AddEventHandler(cache.FilteringResourceEventHandler{
+// FilterFunc: FilterRunRef("example.dev/v0", "Example"),
+// Handler: controller.HandleAll(impl.Enqueue),
+// })
+func FilterRunRef(apiVersion, kind string) func(interface{}) bool {
+ return func(obj interface{}) bool {
+ r, ok := obj.(*v1alpha1.Run)
+ if !ok {
+ // Somehow got informed of a non-Run object.
+ // Ignore.
+ return false
+ }
+ if r == nil || r.Spec.Ref == nil {
+ // These are invalid, but just in case they get
+ // created somehow, don't panic.
+ return false
+ }
+
+ return r.Spec.Ref.APIVersion == apiVersion && r.Spec.Ref.Kind == v1alpha1.TaskKind(kind)
+ }
+}

pkg/controller/filter_test.go

@@ -0,0 +1,105 @@
+/*
+Copyright 2020 The Tekton Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package controller_test
+
+import (
+ "testing"
+
+ "github.com/tektoncd/pipeline/pkg/apis/pipeline/v1alpha1"
+ "github.com/tektoncd/pipeline/pkg/controller"
+)
+
+const (
+ apiVersion = "example.dev/v0"
+ kind = "Example"
+)
+
+func TestFilterRunRef(t *testing.T) {
+ for _, c := range []struct {
+ desc string
+ in interface{}
+ want bool
+ }{{
+ desc: "not a Run",
+ in: struct{}{},
+ want: false,
+ }, {
+ desc: "nil Run",
+ in: (*v1alpha1.Run)(nil),
+ want: false,
+ }, {
+ desc: "nil ref",
+ in: &v1alpha1.Run{
+ Spec: v1alpha1.RunSpec{
+ Ref: nil,
+ },
+ },
+ want: false,
+ }, {
+ desc: "Run without matching apiVersion",
+ in: &v1alpha1.Run{
+ Spec: v1alpha1.RunSpec{
+ Ref: &v1alpha1.TaskRef{
+ APIVersion: "not-matching",
+ Kind: kind,
+ },
+ },
+ },
+ want: false,
+ }, {
+ desc: "Run without matching kind",
+ in: &v1alpha1.Run{
+ Spec: v1alpha1.RunSpec{
+ Ref: &v1alpha1.TaskRef{
+ APIVersion: apiVersion,
+ Kind: "not-matching",
+ },
+ },
+ },
+ want: false,
+ }, {
+ desc: "Run with matching apiVersion and kind",
+ in: &v1alpha1.Run{
+ Spec: v1alpha1.RunSpec{
+ Ref: &v1alpha1.TaskRef{
+ APIVersion: apiVersion,
+ Kind: kind,
+ },
+ },
+ },
+ want: true,
+ }, {
+ desc: "Run with matching apiVersion and kind and name",
+ in: &v1alpha1.Run{
+ Spec: v1alpha1.RunSpec{
+ Ref: &v1alpha1.TaskRef{
+ APIVersion: apiVersion,
+ Kind: kind,
+ Name: "some-name",
+ },
+ },
+ },
+ want: true,
+ }} {
+ t.Run(c.desc, func(t *testing.T) {
+ got := controller.FilterRunRef(apiVersion, kind)(c.in)
+ if got != c.want {
+ t.Fatalf("FilterRunRef(%q, %q) got %t, want %t", apiVersion, kind, got, c.want)
+ }
+ })
+ }
+}