cmd/pinniped: add whoami command

Signed-off-by: Andrew Keesler <akeesler@vmware.com>

cmd/pinniped/cmd/kube_util.go

@@ -0,0 +1,43 @@
+// Copyright 2021 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package cmd
+
+import (
+	"k8s.io/client-go/tools/clientcmd"
+
+	conciergeclientset "go.pinniped.dev/generated/latest/client/concierge/clientset/versioned"
+	"go.pinniped.dev/internal/groupsuffix"
+	"go.pinniped.dev/internal/kubeclient"
+)
+
+// getConciergeClientsetFunc is a function that can return a clientset for the Concierge API given a
+// clientConfig and the apiGroupSuffix with which the API is running.
+type getConciergeClientsetFunc func(clientConfig clientcmd.ClientConfig, apiGroupSuffix string) (conciergeclientset.Interface, error)
+
+// getRealConciergeClientset returns a real implementation of a conciergeclientset.Interface.
+func getRealConciergeClientset(clientConfig clientcmd.ClientConfig, apiGroupSuffix string) (conciergeclientset.Interface, error) {
+	restConfig, err := clientConfig.ClientConfig()
+	if err != nil {
+		return nil, err
+	}
+	client, err := kubeclient.New(
+		kubeclient.WithConfig(restConfig),
+		kubeclient.WithMiddleware(groupsuffix.New(apiGroupSuffix)),
+	)
+	if err != nil {
+		return nil, err
+	}
+	return client.PinnipedConcierge, nil
+}
+
+// newClientConfig returns a clientcmd.ClientConfig given an optional kubeconfig path override and
+// an optional context override.
+func newClientConfig(kubeconfigPathOverride string, currentContextName string) clientcmd.ClientConfig {
+	loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
+	loadingRules.ExplicitPath = kubeconfigPathOverride
+	clientConfig := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, &clientcmd.ConfigOverrides{
+		CurrentContext: currentContextName,
+	})
+	return clientConfig
+}

cmd/pinniped/cmd/kubeconfig.go

@@ -27,31 +27,17 @@ import (
 	conciergev1alpha1 "go.pinniped.dev/generated/latest/apis/concierge/authentication/v1alpha1"
 	conciergeclientset "go.pinniped.dev/generated/latest/client/concierge/clientset/versioned"
 	"go.pinniped.dev/internal/groupsuffix"
-	"go.pinniped.dev/internal/kubeclient"
 )
 
 type kubeconfigDeps struct {
 	getPathToSelf func() (string, error)
-	getClientset  func(clientConfig clientcmd.ClientConfig, apiGroupSuffix string) (conciergeclientset.Interface, error)
+	getClientset  getConciergeClientsetFunc
 }
 
 func kubeconfigRealDeps() kubeconfigDeps {
 	return kubeconfigDeps{
 		getPathToSelf: os.Executable,
-		getClientset: func(clientConfig clientcmd.ClientConfig, apiGroupSuffix string) (conciergeclientset.Interface, error) {
+		getClientset:  getRealConciergeClientset,
-			restConfig, err := clientConfig.ClientConfig()
-			if err != nil {
-				return nil, err
-			}
-			client, err := kubeclient.New(
-				kubeclient.WithConfig(restConfig),
-				kubeclient.WithMiddleware(groupsuffix.New(apiGroupSuffix)),
-			)
-			if err != nil {
-				return nil, err
-			}
-			return client.PinnipedConcierge, nil
-		},
 	}
 }
 
@@ -350,15 +336,6 @@ func lookupAuthenticator(clientset conciergeclientset.Interface, authType, authN
 	return results[0], nil
 }
 
-func newClientConfig(kubeconfigPathOverride string, currentContextName string) clientcmd.ClientConfig {
-	loadingRules := clientcmd.NewDefaultClientConfigLoadingRules()
-	loadingRules.ExplicitPath = kubeconfigPathOverride
-	clientConfig := clientcmd.NewNonInteractiveDeferredLoadingClientConfig(loadingRules, &clientcmd.ConfigOverrides{
-		CurrentContext: currentContextName,
-	})
-	return clientConfig
-}
-
 func writeConfigAsYAML(out io.Writer, config clientcmdapi.Config) error {
 	output, err := clientcmd.Write(config)
 	if err != nil {

cmd/pinniped/cmd/whoami.go

@@ -0,0 +1,298 @@
+// Copyright 2021 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/spf13/cobra"
+	"k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/runtime/serializer"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/client-go/tools/clientcmd"
+
+	identityapi "go.pinniped.dev/generated/latest/apis/concierge/identity"
+	identityv1alpha1 "go.pinniped.dev/generated/latest/apis/concierge/identity/v1alpha1"
+	loginapi "go.pinniped.dev/generated/latest/apis/concierge/login"
+	loginv1alpha1 "go.pinniped.dev/generated/latest/apis/concierge/login/v1alpha1"
+	"go.pinniped.dev/internal/groupsuffix"
+	"go.pinniped.dev/internal/here"
+	"go.pinniped.dev/internal/plog"
+)
+
+//nolint: gochecknoinits
+func init() {
+	rootCmd.AddCommand(newWhoamiCommand(getRealConciergeClientset))
+}
+
+type whoamiFlags struct {
+	outputFormat string // e.g., yaml, json, text
+
+	kubeconfigPath            string
+	kubeconfigContextOverride string
+
+	apiGroupSuffix string
+}
+
+type clusterInfo struct {
+	name string
+	url  string
+}
+
+func newWhoamiCommand(getClientset getConciergeClientsetFunc) *cobra.Command {
+	cmd := &cobra.Command{
+		Args:         cobra.NoArgs, // do not accept positional arguments for this command
+		Use:          "whoami",
+		Short:        "Print information about the current user",
+		SilenceUsage: true,
+	}
+	flags := &whoamiFlags{}
+
+	// flags
+	f := cmd.Flags()
+	f.StringVarP(&flags.outputFormat, "output", "o", "text", "Output format (e.g., 'yaml', 'json', 'text')")
+	f.StringVar(&flags.kubeconfigPath, "kubeconfig", os.Getenv("KUBECONFIG"), "Path to kubeconfig file")
+	f.StringVar(&flags.kubeconfigContextOverride, "kubeconfig-context", "", "Kubeconfig context name (default: current active context)")
+	f.StringVar(&flags.apiGroupSuffix, "api-group-suffix", groupsuffix.PinnipedDefaultSuffix, "Concierge API group suffix")
+
+	cmd.RunE = func(cmd *cobra.Command, _ []string) error {
+		return runWhoami(cmd.OutOrStdout(), getClientset, flags)
+	}
+
+	return cmd
+}
+
+func runWhoami(output io.Writer, getClientset getConciergeClientsetFunc, flags *whoamiFlags) error {
+	clientConfig := newClientConfig(flags.kubeconfigPath, flags.kubeconfigContextOverride)
+	clientset, err := getClientset(clientConfig, flags.apiGroupSuffix)
+	if err != nil {
+		return fmt.Errorf("could not configure Kubernetes client: %w", err)
+	}
+
+	clusterInfo, err := getCurrentCluster(clientConfig)
+	if err != nil {
+		return fmt.Errorf("could not get current cluster info: %w", err)
+	}
+
+	ctx, cancelFunc := context.WithTimeout(context.Background(), time.Second*20)
+	defer cancelFunc()
+	whoAmI, err := clientset.IdentityV1alpha1().WhoAmIRequests().Create(ctx, &identityv1alpha1.WhoAmIRequest{}, metav1.CreateOptions{})
+	if err != nil {
+		hint := ""
+		if errors.IsNotFound(err) {
+			hint = " (is the Pinniped WhoAmI API running and healthy?)"
+		}
+		return fmt.Errorf("could not complete WhoAmIRequest%s: %w", hint, err)
+	}
+
+	if err := writeWhoamiOutput(output, flags, clusterInfo, whoAmI); err != nil {
+		return fmt.Errorf("could not write output: %w", err)
+	}
+
+	return nil
+}
+
+func getCurrentCluster(clientConfig clientcmd.ClientConfig) (*clusterInfo, error) {
+	currentKubeconfig, err := clientConfig.RawConfig()
+	if err != nil {
+		return nil, err
+	}
+
+	unknownClusterInfo := &clusterInfo{name: "???", url: "???"}
+	context, ok := currentKubeconfig.Contexts[currentKubeconfig.CurrentContext]
+	if !ok {
+		return unknownClusterInfo, nil
+	}
+
+	cluster, ok := currentKubeconfig.Clusters[context.Cluster]
+	if !ok {
+		return unknownClusterInfo, nil
+	}
+
+	return &clusterInfo{name: context.Cluster, url: cluster.Server}, nil
+}
+
+func writeWhoamiOutput(output io.Writer, flags *whoamiFlags, cInfo *clusterInfo, whoAmI *identityv1alpha1.WhoAmIRequest) error {
+	switch flags.outputFormat {
+	case "text":
+		return writeWhoamiOutputText(output, cInfo, whoAmI)
+	case "json":
+		return writeWhoamiOutputJSON(output, flags.apiGroupSuffix, whoAmI)
+	case "yaml":
+		return writeWhoamiOutputYAML(output, flags.apiGroupSuffix, whoAmI)
+	default:
+		return fmt.Errorf("unknown output format: %q", flags.outputFormat)
+	}
+}
+
+func writeWhoamiOutputText(output io.Writer, clusterInfo *clusterInfo, whoAmI *identityv1alpha1.WhoAmIRequest) error {
+	fmt.Fprint(output, here.Docf(`
+		Current cluster info:
+
+		Name: %s
+		URL: %s
+
+		Current user info:
+
+		Username: %s
+		Groups: %s
+`, clusterInfo.name, clusterInfo.url, whoAmI.Status.KubernetesUserInfo.User.Username, prettyStrings(whoAmI.Status.KubernetesUserInfo.User.Groups)))
+	return nil
+}
+
+func writeWhoamiOutputJSON(output io.Writer, apiGroupSuffix string, whoAmI *identityv1alpha1.WhoAmIRequest) error {
+	return serialize(output, apiGroupSuffix, whoAmI, runtime.ContentTypeJSON)
+}
+
+func writeWhoamiOutputYAML(output io.Writer, apiGroupSuffix string, whoAmI *identityv1alpha1.WhoAmIRequest) error {
+	return serialize(output, apiGroupSuffix, whoAmI, runtime.ContentTypeYAML)
+}
+
+func serialize(output io.Writer, apiGroupSuffix string, whoAmI *identityv1alpha1.WhoAmIRequest, contentType string) error {
+	scheme, _, identityGV := conciergeschemeNew(apiGroupSuffix)
+	codecs := serializer.NewCodecFactory(scheme)
+	respInfo, ok := runtime.SerializerInfoForMediaType(codecs.SupportedMediaTypes(), contentType)
+	if !ok {
+		return fmt.Errorf("unknown content type: %q", contentType)
+	}
+
+	// I have seen the pretty serializer be nil before, so this will hopefully protect against that
+	// corner.
+	serializer := respInfo.PrettySerializer
+	if serializer == nil {
+		serializer = respInfo.Serializer
+	}
+
+	// Ensure that these fields are set so that the JSON/YAML output tells the full story.
+	whoAmI.APIVersion = identityGV.String()
+	whoAmI.Kind = "WhoAmIRequest"
+
+	return serializer.Encode(whoAmI, output)
+}
+
+func prettyStrings(ss []string) string {
+	b := &strings.Builder{}
+	for i, s := range ss {
+		if i != 0 {
+			b.WriteString(", ")
+		}
+		b.WriteString(s)
+	}
+	return b.String()
+}
+
+// conciergeschemeNew is a temporary private function to stand in place for
+// "go.pinniped.dev/internal/concierge/scheme".New until the later function is merged to main.
+func conciergeschemeNew(apiGroupSuffix string) (_ *runtime.Scheme, login, identity schema.GroupVersion) {
+	// standard set up of the server side scheme
+	scheme := runtime.NewScheme()
+
+	// add the options to empty v1
+	metav1.AddToGroupVersion(scheme, metav1.Unversioned)
+
+	// nothing fancy is required if using the standard group suffix
+	if apiGroupSuffix == groupsuffix.PinnipedDefaultSuffix {
+		schemeBuilder := runtime.NewSchemeBuilder(
+			loginv1alpha1.AddToScheme,
+			loginapi.AddToScheme,
+			identityv1alpha1.AddToScheme,
+			identityapi.AddToScheme,
+		)
+		utilruntime.Must(schemeBuilder.AddToScheme(scheme))
+		return scheme, loginv1alpha1.SchemeGroupVersion, identityv1alpha1.SchemeGroupVersion
+	}
+
+	loginConciergeGroupData, identityConciergeGroupData := groupsuffix.ConciergeAggregatedGroups(apiGroupSuffix)
+
+	addToSchemeAtNewGroup(scheme, loginv1alpha1.GroupName, loginConciergeGroupData.Group, loginv1alpha1.AddToScheme, loginapi.AddToScheme)
+	addToSchemeAtNewGroup(scheme, identityv1alpha1.GroupName, identityConciergeGroupData.Group, identityv1alpha1.AddToScheme, identityapi.AddToScheme)
+
+	// manually register conversions and defaulting into the correct scheme since we cannot directly call AddToScheme
+	schemeBuilder := runtime.NewSchemeBuilder(
+		loginv1alpha1.RegisterConversions,
+		loginv1alpha1.RegisterDefaults,
+		identityv1alpha1.RegisterConversions,
+		identityv1alpha1.RegisterDefaults,
+	)
+	utilruntime.Must(schemeBuilder.AddToScheme(scheme))
+
+	// we do not want to return errors from the scheme and instead would prefer to defer
+	// to the REST storage layer for consistency.  The simplest way to do this is to force
+	// a cache miss from the authenticator cache.  Kube API groups are validated via the
+	// IsDNS1123Subdomain func thus we can easily create a group that is guaranteed never
+	// to be in the authenticator cache.  Add a timestamp just to be extra sure.
+	const authenticatorCacheMissPrefix = "_INVALID_API_GROUP_"
+	authenticatorCacheMiss := authenticatorCacheMissPrefix + time.Now().UTC().String()
+
+	// we do not have any defaulting functions for *loginv1alpha1.TokenCredentialRequest
+	// today, but we may have some in the future.  Calling AddTypeDefaultingFunc overwrites
+	// any previously registered defaulting function.  Thus to make sure that we catch
+	// a situation where we add a defaulting func, we attempt to call it here with a nil
+	// *loginv1alpha1.TokenCredentialRequest.  This will do nothing when there is no
+	// defaulting func registered, but it will almost certainly panic if one is added.
+	scheme.Default((*loginv1alpha1.TokenCredentialRequest)(nil))
+
+	// on incoming requests, restore the authenticator API group to the standard group
+	// note that we are responsible for duplicating this logic for every external API version
+	scheme.AddTypeDefaultingFunc(&loginv1alpha1.TokenCredentialRequest{}, func(obj interface{}) {
+		credentialRequest := obj.(*loginv1alpha1.TokenCredentialRequest)
+
+		if credentialRequest.Spec.Authenticator.APIGroup == nil {
+			// force a cache miss because this is an invalid request
+			plog.Debug("invalid token credential request, nil group", "authenticator", credentialRequest.Spec.Authenticator)
+			credentialRequest.Spec.Authenticator.APIGroup = &authenticatorCacheMiss
+			return
+		}
+
+		restoredGroup, ok := groupsuffix.Unreplace(*credentialRequest.Spec.Authenticator.APIGroup, apiGroupSuffix)
+		if !ok {
+			// force a cache miss because this is an invalid request
+			plog.Debug("invalid token credential request, wrong group", "authenticator", credentialRequest.Spec.Authenticator)
+			credentialRequest.Spec.Authenticator.APIGroup = &authenticatorCacheMiss
+			return
+		}
+
+		credentialRequest.Spec.Authenticator.APIGroup = &restoredGroup
+	})
+
+	return scheme, schema.GroupVersion(loginConciergeGroupData), schema.GroupVersion(identityConciergeGroupData)
+}
+
+func addToSchemeAtNewGroup(scheme *runtime.Scheme, oldGroup, newGroup string, funcs ...func(*runtime.Scheme) error) {
+	// we need a temporary place to register our types to avoid double registering them
+	tmpScheme := runtime.NewScheme()
+	schemeBuilder := runtime.NewSchemeBuilder(funcs...)
+	utilruntime.Must(schemeBuilder.AddToScheme(tmpScheme))
+
+	for gvk := range tmpScheme.AllKnownTypes() {
+		if gvk.GroupVersion() == metav1.Unversioned {
+			continue // metav1.AddToGroupVersion registers types outside of our aggregated API group that we need to ignore
+		}
+
+		if gvk.Group != oldGroup {
+			panic(fmt.Errorf("tmp scheme has type not in the old aggregated API group %s: %s", oldGroup, gvk)) // programmer error
+		}
+
+		obj, err := tmpScheme.New(gvk)
+		if err != nil {
+			panic(err) // programmer error, scheme internal code is broken
+		}
+		newGVK := schema.GroupVersionKind{
+			Group:   newGroup,
+			Version: gvk.Version,
+			Kind:    gvk.Kind,
+		}
+
+		// register the existing type but with the new group in the correct scheme
+		scheme.AddKnownTypeWithName(newGVK, obj)
+	}
+}

cmd/pinniped/cmd/whoami_test.go

@@ -0,0 +1,273 @@
+// Copyright 2021 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package cmd
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"k8s.io/apimachinery/pkg/api/errors"
+	"k8s.io/apimachinery/pkg/runtime"
+	kubetesting "k8s.io/client-go/testing"
+	"k8s.io/client-go/tools/clientcmd"
+
+	identityv1alpha1 "go.pinniped.dev/generated/latest/apis/concierge/identity/v1alpha1"
+	conciergeclientset "go.pinniped.dev/generated/latest/client/concierge/clientset/versioned"
+	fakeconciergeclientset "go.pinniped.dev/generated/latest/client/concierge/clientset/versioned/fake"
+	"go.pinniped.dev/internal/constable"
+	"go.pinniped.dev/internal/here"
+)
+
+func TestWhoami(t *testing.T) {
+	tests := []struct {
+		name                   string
+		args                   []string
+		groupsOverride         []string
+		gettingClientsetErr    error
+		callingAPIErr          error
+		wantError              bool
+		wantStdout, wantStderr string
+	}{
+		{
+			name: "help flag",
+			args: []string{"--help"},
+			wantStdout: here.Doc(`
+				Print information about the current user
+
+				Usage:
+				  whoami [flags]
+
+				Flags:
+				      --api-group-suffix string     Concierge API group suffix (default "pinniped.dev")
+				  -h, --help                        help for whoami
+				      --kubeconfig string           Path to kubeconfig file
+				      --kubeconfig-context string   Kubeconfig context name (default: current active context)
+				  -o, --output string               Output format (e.g., 'yaml', 'json', 'text') (default "text")
+			`),
+		},
+		{
+			name: "text output",
+			args: []string{"--kubeconfig", "testdata/kubeconfig.yaml"},
+			wantStdout: here.Doc(`
+				Current cluster info:
+
+				Name: kind-kind
+				URL: https://fake-server-url-value
+
+				Current user info:
+
+				Username: some-username
+				Groups: some-group-0, some-group-1
+			`),
+		},
+		{
+			name: "text output with long output flag",
+			args: []string{"--kubeconfig", "testdata/kubeconfig.yaml", "--output", "text"},
+			wantStdout: here.Doc(`
+				Current cluster info:
+
+				Name: kind-kind
+				URL: https://fake-server-url-value
+
+				Current user info:
+
+				Username: some-username
+				Groups: some-group-0, some-group-1
+			`),
+		},
+		{
+			name:           "text output with 1 group",
+			args:           []string{"--kubeconfig", "testdata/kubeconfig.yaml", "--output", "text"},
+			groupsOverride: []string{"some-group-0"},
+			wantStdout: here.Doc(`
+				Current cluster info:
+
+				Name: kind-kind
+				URL: https://fake-server-url-value
+
+				Current user info:
+
+				Username: some-username
+				Groups: some-group-0
+			`),
+		},
+		{
+			name:           "text output with no groups",
+			args:           []string{"--kubeconfig", "testdata/kubeconfig.yaml", "--output", "text"},
+			groupsOverride: []string{},
+			wantStdout: here.Doc(`
+				Current cluster info:
+
+				Name: kind-kind
+				URL: https://fake-server-url-value
+
+				Current user info:
+
+				Username: some-username
+				Groups: 
+			`),
+		},
+		{
+			name: "json output",
+			args: []string{"--kubeconfig", "testdata/kubeconfig.yaml", "-o", "json"},
+			wantStdout: here.Doc(`
+				{
+				  "kind": "WhoAmIRequest",
+				  "apiVersion": "identity.concierge.pinniped.dev/v1alpha1",
+				  "metadata": {
+				    "creationTimestamp": null
+				  },
+				  "spec": {},
+				  "status": {
+				    "kubernetesUserInfo": {
+				      "user": {
+				        "username": "some-username",
+				        "groups": [
+				          "some-group-0",
+				          "some-group-1"
+				        ]
+				      }
+				    }
+				  }
+				}`),
+		},
+		{
+			name: "json output with api group suffix flag",
+			args: []string{"--kubeconfig", "testdata/kubeconfig.yaml", "-o", "json", "--api-group-suffix", "tuna.io"},
+			wantStdout: here.Doc(`
+				{
+				  "kind": "WhoAmIRequest",
+				  "apiVersion": "identity.concierge.tuna.io/v1alpha1",
+				  "metadata": {
+				    "creationTimestamp": null
+				  },
+				  "spec": {},
+				  "status": {
+				    "kubernetesUserInfo": {
+				      "user": {
+				        "username": "some-username",
+				        "groups": [
+				          "some-group-0",
+				          "some-group-1"
+				        ]
+				      }
+				    }
+				  }
+				}`),
+		},
+		{
+			name: "yaml output",
+			args: []string{"--kubeconfig", "testdata/kubeconfig.yaml", "-o", "yaml"},
+			wantStdout: here.Doc(`
+				apiVersion: identity.concierge.pinniped.dev/v1alpha1
+				kind: WhoAmIRequest
+				metadata:
+				  creationTimestamp: null
+				spec: {}
+				status:
+				  kubernetesUserInfo:
+				    user:
+				      groups:
+				      - some-group-0
+				      - some-group-1
+				      username: some-username
+			`),
+		},
+		{
+			name: "yaml output with api group suffix",
+			args: []string{"--kubeconfig", "testdata/kubeconfig.yaml", "-o", "yaml", "--api-group-suffix", "tuna.io"},
+			wantStdout: here.Doc(`
+				apiVersion: identity.concierge.tuna.io/v1alpha1
+				kind: WhoAmIRequest
+				metadata:
+				  creationTimestamp: null
+				spec: {}
+				status:
+				  kubernetesUserInfo:
+				    user:
+				      groups:
+				      - some-group-0
+				      - some-group-1
+				      username: some-username
+			`),
+		},
+		{
+			name:       "extra args",
+			args:       []string{"extra-arg"},
+			wantError:  true,
+			wantStderr: "Error: unknown command \"extra-arg\" for \"whoami\"\n",
+		},
+		{
+			name:       "cannot get cluster info",
+			args:       []string{"--kubeconfig", "this-file-does-not-exist"},
+			wantError:  true,
+			wantStderr: "Error: could not get current cluster info: stat this-file-does-not-exist: no such file or directory\n",
+		},
+		{
+			name:                "getting clientset fails",
+			gettingClientsetErr: constable.Error("some get clientset error"),
+			wantError:           true,
+			wantStderr:          "Error: could not configure Kubernetes client: some get clientset error\n",
+		},
+		{
+			name:          "calling API fails",
+			callingAPIErr: constable.Error("some API error"),
+			wantError:     true,
+			wantStderr:    "Error: could not complete WhoAmIRequest: some API error\n",
+		},
+		{
+			name:          "calling API fails because WhoAmI API is not installed",
+			callingAPIErr: errors.NewNotFound(identityv1alpha1.SchemeGroupVersion.WithResource("whoamirequests").GroupResource(), "whatever"),
+			wantError:     true,
+			wantStderr:    "Error: could not complete WhoAmIRequest (is the Pinniped WhoAmI API running and healthy?): whoamirequests.identity.concierge.pinniped.dev \"whatever\" not found\n",
+		},
+	}
+	for _, test := range tests {
+		test := test
+		t.Run(test.name, func(t *testing.T) {
+			getClientset := func(clientConfig clientcmd.ClientConfig, apiGroupSuffix string) (conciergeclientset.Interface, error) {
+				if test.gettingClientsetErr != nil {
+					return nil, test.gettingClientsetErr
+				}
+				clientset := fakeconciergeclientset.NewSimpleClientset()
+				clientset.PrependReactor("create", "whoamirequests", func(_ kubetesting.Action) (bool, runtime.Object, error) {
+					if test.callingAPIErr != nil {
+						return true, nil, test.callingAPIErr
+					}
+					groups := []string{"some-group-0", "some-group-1"}
+					if test.groupsOverride != nil {
+						groups = test.groupsOverride
+					}
+					return true, &identityv1alpha1.WhoAmIRequest{
+						Status: identityv1alpha1.WhoAmIRequestStatus{
+							KubernetesUserInfo: identityv1alpha1.KubernetesUserInfo{
+								User: identityv1alpha1.UserInfo{
+									Username: "some-username",
+									Groups:   groups,
+								},
+							},
+						},
+					}, nil
+				})
+				return clientset, nil
+			}
+			cmd := newWhoamiCommand(getClientset)
+
+			stdout, stderr := bytes.NewBuffer([]byte{}), bytes.NewBuffer([]byte{})
+			cmd.SetOut(stdout)
+			cmd.SetErr(stderr)
+			cmd.SetArgs(test.args)
+
+			err := cmd.Execute()
+			if test.wantError {
+				require.Error(t, err)
+			} else {
+				require.NoError(t, err)
+			}
+			require.Equal(t, test.wantStdout, stdout.String())
+			require.Equal(t, test.wantStderr, stderr.String())
+		})
+	}
+}