Merge pull request #51130 from luxas/fake_discovery

Automatic merge from submit-queue (batch tested with PRs 51335, 51364, 51130, 48075, 50920)

Add the possibility to set return values for the FakeDiscovery implementation

**What this PR does / why we need it**:

As an user of the fake clientset (with the fake discovery), I want to be able to set the fake server's version on demand like this for example:

```go
func TestFakingServerVersion(t *testing.T) {
	client := fakeclientset.NewSimpleClientset()
	fakeDiscovery, ok := client.Discovery().(*fakediscovery.FakeDiscovery)
	if !ok {
		t.Fatalf("couldn't convert Discovery() to *FakeDiscovery")
	}

	testGitCommit := "v1.0.0"
	fakeDiscovery.FakedServerVersion = &version.Info{
		GitCommit: testGitCommit,
	}

	sv, err := client.Discovery().ServerVersion()
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if sv.GitCommit != testGitCommit {
		t.Fatalf("unexpected faked discovery return value: %q", sv.GitCommit)
	}
}
```

This PR makes that possible, in wait for a more sophisticated FakeDiscovery implementation generally.

**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes #

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```
@kubernetes/sig-api-machinery-pr-reviews

federation/client/clientset_generated/federation_clientset/fake/clientset_generated.go

@@ -49,10 +49,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -60,10 +59,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

pkg/client/clientset_generated/internalclientset/fake/clientset_generated.go

@@ -69,10 +69,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -80,10 +79,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/apiextensions-apiserver/pkg/client/clientset/internalclientset/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/client-go/discovery/fake/BUILD

@@ -30,6 +30,9 @@ filegroup(
 
 filegroup(
     name = "all-srcs",
-    srcs = [":package-srcs"],
+    srcs = [
+        ":package-srcs",
+        "//staging/src/k8s.io/client-go/discovery/fake/test:all-srcs",
+    ],
     tags = ["automanaged"],
 )

staging/src/k8s.io/client-go/discovery/fake/discovery.go

@@ -31,8 +31,11 @@ import (
 	"k8s.io/client-go/testing"
 )
 
+// FakeDiscovery implements discovery.DiscoveryInterface and sometimes calls testing.Fake.Invoke with an action,
+// but doesn't respect the return value if any. There is a way to fake static values like ServerVersion by using the Faked... fields on the struct.
 type FakeDiscovery struct {
 	*testing.Fake
+	FakedServerVersion *version.Info
 }
 
 func (c *FakeDiscovery) ServerResourcesForGroupVersion(groupVersion string) (*metav1.APIResourceList, error) {
@@ -74,8 +77,12 @@ func (c *FakeDiscovery) ServerVersion() (*version.Info, error) {
 	action := testing.ActionImpl{}
 	action.Verb = "get"
 	action.Resource = schema.GroupVersionResource{Resource: "version"}
-
 	c.Invokes(action, nil)
+
+	if c.FakedServerVersion != nil {
+		return c.FakedServerVersion, nil
+	}
+
 	versionInfo := kubeversion.Get()
 	return &versionInfo, nil
 }

staging/src/k8s.io/client-go/discovery/fake/test/BUILD

@@ -0,0 +1,25 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_test")
+
+go_test(
+    name = "go_default_test",
+    srcs = ["discovery_test.go"],
+    deps = [
+        "//vendor/k8s.io/apimachinery/pkg/version:go_default_library",
+        "//vendor/k8s.io/client-go/discovery/fake:go_default_library",
+        "//vendor/k8s.io/client-go/kubernetes/fake:go_default_library",
+    ],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

staging/src/k8s.io/client-go/discovery/fake/test/discovery_test.go

@@ -0,0 +1,46 @@
+/*
+Copyright 2017 The Kubernetes 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 fake
+
+import (
+	"testing"
+
+	"k8s.io/apimachinery/pkg/version"
+	fakediscovery "k8s.io/client-go/discovery/fake"
+	fakeclientset "k8s.io/client-go/kubernetes/fake"
+)
+
+func TestFakingServerVersion(t *testing.T) {
+	client := fakeclientset.NewSimpleClientset()
+	fakeDiscovery, ok := client.Discovery().(*fakediscovery.FakeDiscovery)
+	if !ok {
+		t.Fatalf("couldn't convert Discovery() to *FakeDiscovery")
+	}
+
+	testGitCommit := "v1.0.0"
+	fakeDiscovery.FakedServerVersion = &version.Info{
+		GitCommit: testGitCommit,
+	}
+
+	sv, err := client.Discovery().ServerVersion()
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if sv.GitCommit != testGitCommit {
+		t.Fatalf("unexpected faked discovery return value: %q", sv.GitCommit)
+	}
+}

staging/src/k8s.io/client-go/kubernetes/fake/clientset_generated.go

@@ -87,10 +87,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -98,10 +97,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/code-generator/cmd/client-gen/generators/fake/generator_fake_for_clientset.go

@@ -117,10 +117,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -128,10 +127,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 `
 

staging/src/k8s.io/code-generator/test/clientset/internal/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/code-generator/test/clientset/versioned/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/kube-aggregator/pkg/client/clientset_generated/clientset/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/kube-aggregator/pkg/client/clientset_generated/internalclientset/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/metrics/pkg/client/clientset_generated/clientset/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/sample-apiserver/pkg/client/clientset_generated/clientset/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}

staging/src/k8s.io/sample-apiserver/pkg/client/clientset_generated/internalclientset/fake/clientset_generated.go

@@ -41,10 +41,9 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 
 	fakePtr := testing.Fake{}
 	fakePtr.AddReactor("*", "*", testing.ObjectReaction(o))
-
 	fakePtr.AddWatchReactor("*", testing.DefaultWatchReactor(watch.NewFake(), nil))
 
-	return &Clientset{fakePtr}
+	return &Clientset{fakePtr, &fakediscovery.FakeDiscovery{Fake: &fakePtr}}
 }
 
 // Clientset implements clientset.Interface. Meant to be embedded into a
@@ -52,10 +51,11 @@ func NewSimpleClientset(objects ...runtime.Object) *Clientset {
 // you want to test easier.
 type Clientset struct {
 	testing.Fake
+	discovery *fakediscovery.FakeDiscovery
 }
 
 func (c *Clientset) Discovery() discovery.DiscoveryInterface {
-	return &fakediscovery.FakeDiscovery{Fake: &c.Fake}
+	return c.discovery
 }
 
 var _ clientset.Interface = &Clientset{}