Adds command objects for cluster check-certificate-expiration

Reference:- https://hackmd.io/aGaz7YXSSHybGcyol8vYEw
Previous work:- https://review.opendev.org/#/c/755291/

Below is the complete ordered flow of PS for the feature:
https://review.opendev.org/#/c/760498/ - Cobra command
https://review.opendev.org/#/c/760501/ - Command Objects
https://review.opendev.org/#/c/760504/ - TLS check
https://review.opendev.org/#/c/760517/ - Kubeconf check
https://review.opendev.org/#/c/760532/ - Node check
https://review.opendev.org/#/c/760537/ - Combined Unit tests

Change-Id: Ie0fac7799724b7fb2255e387b7e90b26159bda5c
Relates-To: #391

cmd/cluster/checkexpiration/checkexpiration.go

@@ -17,8 +17,9 @@ package checkexpiration
 import (
 	"github.com/spf13/cobra"
 
+	"opendev.org/airship/airshipctl/pkg/cluster/checkexpiration"
 	"opendev.org/airship/airshipctl/pkg/config"
-	"opendev.org/airship/airshipctl/pkg/errors"
+	"opendev.org/airship/airshipctl/pkg/k8s/client"
 	"opendev.org/airship/airshipctl/pkg/log"
 )
 
@@ -54,25 +55,31 @@ airshipctl cluster check-certificate-expiration -t 30 -o yaml --kubeconfig testc
 
 // NewCheckCommand creates a new command for generating secret information
 func NewCheckCommand(cfgFactory config.Factory) *cobra.Command {
-	var threshold int
+	c := &checkexpiration.CheckCommand{
-	var contentType, kubeconfig string
+		Options:       checkexpiration.CheckFlags{},
+		CfgFactory:    cfgFactory,
+		ClientFactory: client.DefaultClient,
+	}
+
 	checkCmd := &cobra.Command{
 		Use:     "check-certificate-expiration",
 		Short:   "Check for expiring TLS certificates, secrets and kubeconfigs in the kubernetes cluster",
 		Long:    checkLong[1:],
 		Example: checkExample,
 		RunE: func(cmd *cobra.Command, args []string) error {
-			return errors.ErrNotImplemented{What: "check certificate expiration"}
+			return c.RunE(cmd.OutOrStdout())
 		},
 	}
 
-	checkCmd.Flags().IntVarP(&threshold, "threshold", "t", -1,
+	checkCmd.Flags().IntVarP(&c.Options.Threshold, "threshold", "t", -1,
 		"The max expiration threshold in days before a certificate is"+
 			" expiring. Displays all the certificates by default")
-	checkCmd.Flags().StringVarP(&contentType, "output", "o", "json", "Convert "+
+	checkCmd.Flags().StringVarP(&c.Options.FormatType, "output", "o", "json", "Convert "+
 		"output to yaml or json")
-	checkCmd.Flags().StringVar(&kubeconfig, kubeconfigFlag, "",
+	checkCmd.Flags().StringVar(&c.Options.Kubeconfig, kubeconfigFlag, "",
 		"Path to kubeconfig associated with cluster being managed")
+	checkCmd.Flags().StringVar(&c.Options.KubeContext, "kubecontext", "",
+		"Kubeconfig context to be used")
 
 	err := checkCmd.MarkFlagRequired(kubeconfigFlag)
 	if err != nil {

cmd/cluster/checkexpiration/testdata/TestCheckExpirationGoldenOutput/check-expiration-with-help.golden

@@ -28,7 +28,8 @@ airshipctl cluster check-certificate-expiration -t 30 -o yaml --kubeconfig testc
 
 
 Flags:
-  -h, --help                help for check-certificate-expiration
+  -h, --help                 help for check-certificate-expiration
-      --kubeconfig string   Path to kubeconfig associated with cluster being managed
+      --kubeconfig string    Path to kubeconfig associated with cluster being managed
-  -o, --output string       Convert output to yaml or json (default "json")
+      --kubecontext string   Kubeconfig context to be used
-  -t, --threshold int       The max expiration threshold in days before a certificate is expiring. Displays all the certificates by default (default -1)
+  -o, --output string        Convert output to yaml or json (default "json")
+  -t, --threshold int        The max expiration threshold in days before a certificate is expiring. Displays all the certificates by default (default -1)

docs/source/cli/airshipctl_cluster_check-certificate-expiration.md

@@ -40,10 +40,11 @@ airshipctl cluster check-certificate-expiration -t 30 -o yaml --kubeconfig testc
 ### Options
 
 ```
-  -h, --help                help for check-certificate-expiration
+  -h, --help                 help for check-certificate-expiration
-      --kubeconfig string   Path to kubeconfig associated with cluster being managed
+      --kubeconfig string    Path to kubeconfig associated with cluster being managed
-  -o, --output string       Convert output to yaml or json (default "json")
+      --kubecontext string   Kubeconfig context to be used
-  -t, --threshold int       The max expiration threshold in days before a certificate is expiring. Displays all the certificates by default (default -1)
+  -o, --output string        Convert output to yaml or json (default "json")
+  -t, --threshold int        The max expiration threshold in days before a certificate is expiring. Displays all the certificates by default (default -1)
 ```
 
 ### Options inherited from parent commands

pkg/cluster/checkexpiration/checkexpiration.go

@@ -0,0 +1,60 @@
+/*
+ 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
+
+     https://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 checkexpiration
+
+import (
+	"opendev.org/airship/airshipctl/pkg/config"
+	"opendev.org/airship/airshipctl/pkg/errors"
+	"opendev.org/airship/airshipctl/pkg/k8s/client"
+)
+
+// CertificateExpirationStore is the customized client store
+type CertificateExpirationStore struct {
+	Kclient  client.Interface
+	Settings config.Factory
+}
+
+// Expiration captures expiration information of all expirable entities in the cluster
+type Expiration struct{}
+
+// NewStore returns an instance of a CertificateExpirationStore
+func NewStore(cfgFactory config.Factory, clientFactory client.Factory,
+	kubeconfig string, _ string) (CertificateExpirationStore, error) {
+	airshipconfig, err := cfgFactory()
+	if err != nil {
+		return CertificateExpirationStore{}, err
+	}
+
+	// TODO (guhan) Allow kube context to be passed to client Factory
+	// 4th argument in NewStore takes kube context and is ignored for now.
+	// To be modified post #388. Refer to
+	// https://review.opendev.org/#/c/760501/7/pkg/cluster/checkexpiration/command.go@31
+	kclient, err := clientFactory(airshipconfig.LoadedConfigPath(), kubeconfig)
+	if err != nil {
+		return CertificateExpirationStore{}, err
+	}
+
+	return CertificateExpirationStore{
+		Kclient:  kclient,
+		Settings: cfgFactory,
+	}, nil
+}
+
+// GetExpiringCertificates checks for the expiration data
+// NOT IMPLEMENTED (guhan)
+// TODO (guhan) check for TLS certificates, workload kubeconfig and node certificates
+func (store CertificateExpirationStore) GetExpiringCertificates(expirationThreshold int) (Expiration, error) {
+	return Expiration{}, errors.ErrNotImplemented{What: "check certificate expiration logic"}
+}

pkg/cluster/checkexpiration/command.go

@@ -0,0 +1,73 @@
+/*
+ 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
+
+     https://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 checkexpiration
+
+import (
+	"encoding/json"
+	"io"
+	"strings"
+
+	"opendev.org/airship/airshipctl/pkg/config"
+	"opendev.org/airship/airshipctl/pkg/k8s/client"
+	"opendev.org/airship/airshipctl/pkg/util/yaml"
+)
+
+// CheckFlags flags given for checking the expiration
+type CheckFlags struct {
+	Threshold   int
+	FormatType  string
+	Kubeconfig  string
+	KubeContext string
+}
+
+// CheckCommand check expiration command
+type CheckCommand struct {
+	Options       CheckFlags
+	CfgFactory    config.Factory
+	ClientFactory client.Factory
+}
+
+// RunE is the implementation of check command
+func (c *CheckCommand) RunE(w io.Writer) error {
+	if !strings.EqualFold(c.Options.FormatType, "json") && !strings.EqualFold(c.Options.FormatType, "yaml") {
+		return ErrInvalidFormat{RequestedFormat: c.Options.FormatType}
+	}
+
+	secretStore, err := NewStore(c.CfgFactory, c.ClientFactory, c.Options.Kubeconfig, c.Options.KubeContext)
+	if err != nil {
+		return err
+	}
+
+	expirationInfo, err := secretStore.GetExpiringCertificates(c.Options.Threshold)
+	if err != nil {
+		return err
+	}
+	if c.Options.FormatType == "yaml" {
+		err = yaml.WriteOut(w, expirationInfo)
+		if err != nil {
+			return err
+		}
+	} else {
+		buffer, err := json.MarshalIndent(expirationInfo, "", "    ")
+		if err != nil {
+			return err
+		}
+		_, err = w.Write(buffer)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

pkg/cluster/checkexpiration/command_test.go

@@ -0,0 +1,106 @@
+/*
+ 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
+
+     https://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 checkexpiration_test
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"k8s.io/apimachinery/pkg/runtime"
+
+	"opendev.org/airship/airshipctl/pkg/cluster/checkexpiration"
+	"opendev.org/airship/airshipctl/pkg/config"
+	"opendev.org/airship/airshipctl/pkg/k8s/client"
+	"opendev.org/airship/airshipctl/pkg/k8s/client/fake"
+	"opendev.org/airship/airshipctl/testutil"
+)
+
+const (
+	testNotImplementedErr = "not implemented: check certificate expiration logic"
+)
+
+func TestRunE(t *testing.T) {
+	tests := []struct {
+		testCaseName   string
+		testErr        string
+		checkFlags     checkexpiration.CheckFlags
+		cfgFactory     config.Factory
+		expectedOutput string
+	}{
+		{
+			testCaseName: "invalid-input-format",
+			cfgFactory: func() (*config.Config, error) {
+				return nil, nil
+			},
+			checkFlags: checkexpiration.CheckFlags{
+				Threshold:  0,
+				FormatType: "test-yaml",
+			},
+			testErr: checkexpiration.ErrInvalidFormat{RequestedFormat: "test-yaml"}.Error(),
+		},
+		{
+			testCaseName: "valid-input-format-json",
+			cfgFactory: func() (*config.Config, error) {
+				cfg, _ := testutil.InitConfig(t)
+				return cfg, nil
+			},
+			checkFlags: checkexpiration.CheckFlags{
+				Threshold:  5000,
+				FormatType: "json",
+				Kubeconfig: "",
+			},
+			testErr: testNotImplementedErr,
+		},
+		{
+			testCaseName: "valid-input-format-yaml",
+			cfgFactory: func() (*config.Config, error) {
+				cfg, _ := testutil.InitConfig(t)
+				return cfg, nil
+			},
+			checkFlags: checkexpiration.CheckFlags{
+				Threshold:  5000,
+				FormatType: "yaml",
+			},
+			testErr: testNotImplementedErr,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.testCaseName, func(t *testing.T) {
+			var objects []runtime.Object
+			// TODO (guhan) append a dummy object for testing
+			ra := fake.WithTypedObjects(objects...)
+
+			command := checkexpiration.CheckCommand{
+				Options:    tt.checkFlags,
+				CfgFactory: tt.cfgFactory,
+				ClientFactory: func(_ string, _ string) (client.Interface, error) {
+					return fake.NewClient(ra), nil
+				},
+			}
+
+			var buffer bytes.Buffer
+			err := command.RunE(&buffer)
+
+			if tt.testErr != "" {
+				require.Error(t, err)
+				assert.Contains(t, err.Error(), tt.testErr)
+			}
+			// TODO (guhan) add else part to check the actual vs expected o/p
+		})
+	}
+}

pkg/cluster/checkexpiration/errors.go

@@ -0,0 +1,26 @@
+/*
+ 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
+
+     https://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 checkexpiration
+
+import "fmt"
+
+// ErrInvalidFormat is called when the user provides format other than yaml/json
+type ErrInvalidFormat struct {
+	RequestedFormat string
+}
+
+func (e ErrInvalidFormat) Error() string {
+	return fmt.Sprintf("invalid output format specified %s. Allowed values are json|yaml", e.RequestedFormat)
+}