add explain tests for openapiv3

staging/src/k8s.io/kubectl/pkg/cmd/explain/explain_test.go

@@ -14,24 +14,31 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package explain
+package explain_test
 
 import (
+	"errors"
 	"path/filepath"
-	"strings"
+	"regexp"
 	"testing"
 
 	"github.com/stretchr/testify/require"
 	"k8s.io/apimachinery/pkg/api/meta"
 	sptest "k8s.io/apimachinery/pkg/util/strategicpatch/testing"
 	"k8s.io/cli-runtime/pkg/genericclioptions"
+	"k8s.io/client-go/discovery"
+	openapiclient "k8s.io/client-go/openapi"
+	"k8s.io/client-go/rest"
+	clienttestutil "k8s.io/client-go/util/testing"
+	"k8s.io/kubectl/pkg/cmd/explain"
 	cmdtesting "k8s.io/kubectl/pkg/cmd/testing"
 	cmdutil "k8s.io/kubectl/pkg/cmd/util"
 	"k8s.io/kubectl/pkg/util/openapi"
 )
 
 var (
-	fakeSchema        = sptest.Fake{Path: filepath.Join("..", "..", "..", "testdata", "openapi", "swagger.json")}
+	testDataPath      = filepath.Join("..", "..", "..", "testdata")
+	fakeSchema        = sptest.Fake{Path: filepath.Join(testDataPath, "openapi", "swagger.json")}
 	FakeOpenAPISchema = testOpenAPISchema{
 		OpenAPISchemaFn: func() (openapi.Resources, error) {
 			s, err := fakeSchema.OpenAPISchema()
@@ -51,8 +58,8 @@ func TestExplainInvalidArgs(t *testing.T) {
 	tf := cmdtesting.NewTestFactory()
 	defer tf.Cleanup()
 
-	opts := NewExplainOptions("kubectl", genericclioptions.NewTestIOStreamsDiscard())
-	cmd := NewCmdExplain("kubectl", tf, genericclioptions.NewTestIOStreamsDiscard())
+	opts := explain.NewExplainOptions("kubectl", genericclioptions.NewTestIOStreamsDiscard())
+	cmd := explain.NewCmdExplain("kubectl", tf, genericclioptions.NewTestIOStreamsDiscard())
 	err := opts.Complete(tf, cmd, []string{})
 	if err != nil {
 		t.Fatalf("unexpected error %v", err)
@@ -78,8 +85,8 @@ func TestExplainNotExistResource(t *testing.T) {
 	tf := cmdtesting.NewTestFactory()
 	defer tf.Cleanup()
 
-	opts := NewExplainOptions("kubectl", genericclioptions.NewTestIOStreamsDiscard())
-	cmd := NewCmdExplain("kubectl", tf, genericclioptions.NewTestIOStreamsDiscard())
+	opts := explain.NewExplainOptions("kubectl", genericclioptions.NewTestIOStreamsDiscard())
+	cmd := explain.NewCmdExplain("kubectl", tf, genericclioptions.NewTestIOStreamsDiscard())
 	err := opts.Complete(tf, cmd, []string{"foo"})
 	if err != nil {
 		t.Fatalf("unexpected error %v", err)
@@ -96,30 +103,106 @@ func TestExplainNotExistResource(t *testing.T) {
 	}
 }
 
-func TestExplainNotExistVersion(t *testing.T) {
-	tf := cmdtesting.NewTestFactory()
-	defer tf.Cleanup()
+type explainTestCase struct {
+	Name               string
+	Args               []string
+	Flags              map[string]string
+	ExpectPattern      []string
+	ExpectErrorPattern string
 
-	opts := NewExplainOptions("kubectl", genericclioptions.NewTestIOStreamsDiscard())
-	cmd := NewCmdExplain("kubectl", tf, genericclioptions.NewTestIOStreamsDiscard())
-	err := opts.Complete(tf, cmd, []string{"pods"})
+	// Custom OpenAPI V3 client to use for the test. If nil, a default one will
+	// be provided
+	OpenAPIV3SchemaFn func() (openapiclient.Client, error)
+}
+
+var explainV2Cases = []explainTestCase{
+	{
+		Name:          "Basic",
+		Args:          []string{"pods"},
+		ExpectPattern: []string{`\s*KIND:[\t ]*Pod\s*`},
+	},
+	{
+		Name:          "Recursive",
+		Args:          []string{"pods"},
+		Flags:         map[string]string{"recursive": "true"},
+		ExpectPattern: []string{`\s*KIND:[\t ]*Pod\s*`},
+	},
+	{
+		Name:          "DefaultAPIVersion",
+		Args:          []string{"horizontalpodautoscalers"},
+		Flags:         map[string]string{"api-version": "autoscaling/v1"},
+		ExpectPattern: []string{`\s*VERSION:[\t ]*(v1|autoscaling/v1)\s*`},
+	},
+	{
+		Name:               "NonExistingAPIVersion",
+		Args:               []string{"pods"},
+		Flags:              map[string]string{"api-version": "v99"},
+		ExpectErrorPattern: `couldn't find resource for \"/v99, (Kind=Pod|Resource=pods)\"`,
+	},
+	{
+		Name:               "NonExistingResource",
+		Args:               []string{"foo"},
+		ExpectErrorPattern: `the server doesn't have a resource type "foo"`,
+	},
+}
+
+func TestExplainOpenAPIV2(t *testing.T) {
+	runExplainTestCases(t, explainV2Cases)
+}
+
+func TestExplainOpenAPIV3(t *testing.T) {
+
+	fallbackV3SchemaFn := func() (openapiclient.Client, error) {
+		fakeDiscoveryClient := discovery.NewDiscoveryClientForConfigOrDie(&rest.Config{Host: "https://not.a.real.site:65543/"})
+		return fakeDiscoveryClient.OpenAPIV3(), nil
+	}
+	// Returns a client that causes fallback to v2 implementation
+	cases := []explainTestCase{
+		{
+			// No --output, but OpenAPIV3 enabled should fall back to v2 if
+			// v2 is not available. Shows this by making openapiv3 client
+			// point to a bad URL. So the fact the proper data renders is
+			// indication v2 was used instead.
+			Name:              "Fallback",
+			Args:              []string{"pods"},
+			ExpectPattern:     []string{`\s*KIND:[\t ]*Pod\s*`},
+			OpenAPIV3SchemaFn: fallbackV3SchemaFn,
+		},
+		{
+			Name:          "NonDefaultAPIVersion",
+			Args:          []string{"horizontalpodautoscalers"},
+			Flags:         map[string]string{"api-version": "autoscaling/v2"},
+			ExpectPattern: []string{`\s*VERSION:[\t ]*(v2|autoscaling/v2)\s*`},
+		},
+		{
+			// Show that explicitly specifying --output plaintext-openapiv2 causes
+			// old implementation to be used even though OpenAPIV3 is enabled
+			Name:              "OutputPlaintextV2",
+			Args:              []string{"pods"},
+			Flags:             map[string]string{"output": "plaintext-openapiv2"},
+			ExpectPattern:     []string{`\s*KIND:[\t ]*Pod\s*`},
+			OpenAPIV3SchemaFn: fallbackV3SchemaFn,
+		},
+	}
+	cases = append(cases, explainV2Cases...)
+
+	cmdtesting.WithAlphaEnvs([]cmdutil.FeatureGate{cmdutil.ExplainOpenapiV3}, t, func(t *testing.T) {
+		runExplainTestCases(t, cases)
+	})
+}
+
+func runExplainTestCases(t *testing.T, cases []explainTestCase) {
+	fakeServer, err := clienttestutil.NewFakeOpenAPIV3Server(filepath.Join(testDataPath, "openapi", "v3"))
 	if err != nil {
-		t.Fatalf("unexpected error %v", err)
+		t.Fatalf("error starting fake openapi server: %v", err.Error())
 	}
-	opts.APIVersion = "v99"
+	defer fakeServer.HttpServer.Close()
 
-	err = opts.Validate()
-	if err != nil {
-		t.Fatalf("unexpected error %v", err)
+	openapiV3SchemaFn := func() (openapiclient.Client, error) {
+		fakeDiscoveryClient := discovery.NewDiscoveryClientForConfigOrDie(&rest.Config{Host: fakeServer.HttpServer.URL})
+		return fakeDiscoveryClient.OpenAPIV3(), nil
 	}
 
-	err = opts.Run()
-	if err.Error() != "couldn't find resource for \"/v99, Kind=Pod\"" {
-		t.Errorf("unexpected non-error")
-	}
-}
-
-func TestExplain(t *testing.T) {
 	tf := cmdtesting.NewTestFactory()
 	defer tf.Cleanup()
 
@@ -127,29 +210,72 @@ func TestExplain(t *testing.T) {
 	tf.ClientConfigVal = cmdtesting.DefaultClientConfig()
 
 	ioStreams, _, buf, _ := genericclioptions.NewTestIOStreams()
-	cmd := NewCmdExplain("kubectl", tf, ioStreams)
-	cmd.Run(cmd, []string{"pods"})
-	if !strings.Contains(buf.String(), "KIND:     Pod") {
-		t.Fatalf("expected output should include pod kind")
+
+	type catchFatal error
+
+	for _, tcase := range cases {
+
+		t.Run(tcase.Name, func(t *testing.T) {
+
+			// Catch os.Exit calls for tests which expect them
+			// and replace them with panics that we catch in each test
+			// to check if it is expected.
+			cmdutil.BehaviorOnFatal(func(str string, code int) {
+				panic(catchFatal(errors.New(str)))
+			})
+			defer cmdutil.DefaultBehaviorOnFatal()
+
+			var err error
+
+			func() {
+				defer func() {
+					// Catch panic and check at end of test if it is
+					// expected.
+					if panicErr := recover(); panicErr != nil {
+						if e := panicErr.(catchFatal); e != nil {
+							err = e
+						} else {
+							panic(panicErr)
+						}
+					}
+				}()
+
+				if tcase.OpenAPIV3SchemaFn != nil {
+					tf.OpenAPIV3ClientFunc = tcase.OpenAPIV3SchemaFn
+				} else {
+					tf.OpenAPIV3ClientFunc = openapiV3SchemaFn
 				}
 
-	cmd.Flags().Set("recursive", "true")
-	cmd.Run(cmd, []string{"pods"})
-	if !strings.Contains(buf.String(), "KIND:     Pod") ||
-		!strings.Contains(buf.String(), "annotations\t<map[string]string>") {
-		t.Fatalf("expected output should include pod kind")
+				cmd := explain.NewCmdExplain("kubectl", tf, ioStreams)
+				for k, v := range tcase.Flags {
+					if err := cmd.Flags().Set(k, v); err != nil {
+						t.Fatal(err)
+					}
+				}
+				cmd.Run(cmd, tcase.Args)
+			}()
+
+			for _, rexp := range tcase.ExpectPattern {
+				if matched, err := regexp.MatchString(rexp, buf.String()); err != nil || !matched {
+					if err != nil {
+						t.Error(err)
+					} else {
+						t.Errorf("expected output to match regex:\n\t%s\ninstead got:\n\t%s", rexp, buf.String())
+					}
+				}
 			}
 
-	cmd.Flags().Set("api-version", "batch/v1")
-	cmd.Run(cmd, []string{"cronjobs"})
-	if !strings.Contains(buf.String(), "VERSION:  batch/v1") {
-		t.Fatalf("expected output should include pod batch/v1")
+			if err != nil {
+				if matched, regexErr := regexp.MatchString(tcase.ExpectErrorPattern, err.Error()); len(tcase.ExpectErrorPattern) == 0 || regexErr != nil || !matched {
+					t.Fatalf("unexpected error: %s did not match regex %s (%v)", err.Error(),
+						tcase.ExpectErrorPattern, regexErr)
 				}
+			} else if len(tcase.ExpectErrorPattern) > 0 {
+				t.Fatalf("did not trigger expected error: %s in output:\n%s", tcase.ExpectErrorPattern, buf.String())
+			}
+		})
 
-	cmd.Flags().Set("api-version", "batch/v1beta1")
-	cmd.Run(cmd, []string{"cronjobs"})
-	if !strings.Contains(buf.String(), "VERSION:  batch/v1beta1") {
-		t.Fatalf("expected output should include pod batch/v1beta1")
+		buf.Reset()
 	}
 }
 
@@ -161,11 +287,11 @@ func TestAlphaEnablement(t *testing.T) {
 		f := cmdtesting.NewTestFactory()
 		defer f.Cleanup()
 
-		cmd := NewCmdExplain("kubectl", f, genericclioptions.NewTestIOStreamsDiscard())
+		cmd := explain.NewCmdExplain("kubectl", f, genericclioptions.NewTestIOStreamsDiscard())
 		require.Nil(t, cmd.Flags().Lookup(flag), "flag %q should not be registered without the %q feature enabled", flag, feature)
 
 		cmdtesting.WithAlphaEnvs([]cmdutil.FeatureGate{feature}, t, func(t *testing.T) {
-			cmd := NewCmdExplain("kubectl", f, genericclioptions.NewTestIOStreamsDiscard())
+			cmd := explain.NewCmdExplain("kubectl", f, genericclioptions.NewTestIOStreamsDiscard())
 			require.NotNil(t, cmd.Flags().Lookup(flag), "flag %q should be registered with the %q feature enabled", flag, feature)
 		})
 	}