feat: implement talosctl config info command

Closes #3852.

Signed-off-by: Alexey Palazhchenko <alexey.palazhchenko@gmail.com>

cmd/talosctl/cmd/mgmt/gen/crt.go

@@ -38,7 +38,7 @@ var genCrtCmd = &cobra.Command{
 
 		caPemBlock, _ := pem.Decode(caBytes)
 		if caPemBlock == nil {
-			return fmt.Errorf("error decoding cert PEM: %s", err)
+			return fmt.Errorf("error decoding cert PEM")
 		}
 
 		caCrt, err := stdlibx509.ParseCertificate(caPemBlock.Bytes)
@@ -53,7 +53,7 @@ var genCrtCmd = &cobra.Command{
 
 		keyPemBlock, _ := pem.Decode(keyBytes)
 		if keyPemBlock == nil {
-			return fmt.Errorf("error decoding key PEM: %s", err)
+			return fmt.Errorf("error decoding key PEM")
 		}
 
 		caKey, err := stdlibx509.ParsePKCS8PrivateKey(keyPemBlock.Bytes)
@@ -68,7 +68,7 @@ var genCrtCmd = &cobra.Command{
 
 		csrPemBlock, _ := pem.Decode(csrBytes)
 		if csrPemBlock == nil {
-			return fmt.Errorf("error parsing CSR PEM: %s", err)
+			return fmt.Errorf("error parsing CSR PEM")
 		}
 
 		ccsr, err := stdlibx509.ParseCertificateRequest(csrPemBlock.Bytes)

cmd/talosctl/cmd/mgmt/gen/csr.go

@@ -40,7 +40,7 @@ var genCSRCmd = &cobra.Command{
 
 		pemBlock, _ := pem.Decode(keyBytes)
 		if pemBlock == nil {
-			return fmt.Errorf("error decoding PEM: %s", err)
+			return fmt.Errorf("error decoding PEM")
 		}
 
 		keyEC, err := stdlibx509.ParsePKCS8PrivateKey(pemBlock.Bytes)

cmd/talosctl/cmd/talos/config.go

@@ -5,16 +5,21 @@
 package talos
 
 import (
+	"bytes"
 	"context"
+	"crypto/x509"
 	"encoding/base64"
+	"encoding/pem"
 	"fmt"
 	"io/ioutil"
 	"os"
 	"sort"
 	"strings"
 	"text/tabwriter"
+	"text/template"
 	"time"
 
+	"github.com/dustin/go-humanize"
 	"github.com/spf13/cobra"
 	"google.golang.org/protobuf/types/known/durationpb"
 
@@ -323,6 +328,88 @@ var configNewCmd = &cobra.Command{
 	},
 }
 
+// configNewCmd represents the `config info` command output template.
+var configInfoCmdTemplate = template.Must(template.New("configInfoCmdTemplate").Option("missingkey=error").Parse(strings.TrimSpace(`
+Current context:     {{ .Context }}
+Nodes:               {{ .Nodes }}
+Endpoints:           {{ .Endpoints }}
+Roles:               {{ .Roles }}
+Certificate expires: {{ .CertTTL }} ({{ .CertNotAfter }})
+`)))
+
+// configInfoCommand implements `config info` command logic.
+//
+//nolint:goconst
+func configInfoCommand(config *clientconfig.Config, now time.Time) (string, error) {
+	context := config.Contexts[config.Context]
+
+	b, err := base64.StdEncoding.DecodeString(context.Crt)
+	if err != nil {
+		return "", err
+	}
+
+	block, _ := pem.Decode(b)
+	if block == nil {
+		return "", fmt.Errorf("error decoding PEM")
+	}
+
+	crt, err := x509.ParseCertificate(block.Bytes)
+	if err != nil {
+		return "", err
+	}
+
+	roles, _ := role.Parse(crt.Subject.Organization)
+
+	nodesS := "not defined"
+	if len(context.Nodes) > 0 {
+		nodesS = strings.Join(context.Nodes, ", ")
+	}
+
+	endpointsS := "not defined"
+	if len(context.Endpoints) > 0 {
+		endpointsS = strings.Join(context.Endpoints, ", ")
+	}
+
+	rolesS := "not defined"
+	if s := roles.Strings(); len(s) > 0 {
+		rolesS = strings.Join(s, ", ")
+	}
+
+	var res bytes.Buffer
+	err = configInfoCmdTemplate.Execute(&res, map[string]string{
+		"Context":      config.Context,
+		"Nodes":        nodesS,
+		"Endpoints":    endpointsS,
+		"Roles":        rolesS,
+		"CertTTL":      humanize.RelTime(crt.NotAfter, now, "ago", "from now"),
+		"CertNotAfter": crt.NotAfter.UTC().Format("2006-01-02"),
+	})
+
+	return res.String() + "\n", err
+}
+
+// configInfoCmd represents the `config info` command.
+var configInfoCmd = &cobra.Command{
+	Use:   "info",
+	Short: "Show information about the current context",
+	Args:  cobra.NoArgs,
+	RunE: func(cmd *cobra.Command, args []string) error {
+		c, err := openConfigAndContext("")
+		if err != nil {
+			return err
+		}
+
+		res, err := configInfoCommand(c, time.Now())
+		if err != nil {
+			return err
+		}
+
+		fmt.Print(res)
+
+		return nil
+	},
+}
+
 func init() {
 	configCmd.AddCommand(
 		configEndpointCmd,
@@ -332,6 +419,7 @@ func init() {
 		configGetContextsCmd,
 		configMergeCmd,
 		configNewCmd,
+		configInfoCmd,
 	)
 
 	configAddCmd.Flags().StringVar(&configAddCmdFlags.ca, "ca", "", "the path to the CA certificate")

cmd/talosctl/cmd/talos/config_test.go

@@ -0,0 +1,106 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package talos //nolint:testpackage // to test unexported function
+
+import (
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	clientconfig "github.com/talos-systems/talos/pkg/machinery/client/config"
+)
+
+func TestConfigInfoCommand(t *testing.T) {
+	t.Parallel()
+
+	now := time.Date(2021, 7, 5, 22, 6, 42, 0, time.UTC)
+
+	//nolint:lll
+	testCases := []struct {
+		name     string
+		config   string
+		expected string
+	}{
+		{
+			name: "Default",
+			config: `
+context: no-roles
+contexts:
+    no-roles:
+        endpoints:
+            - 172.20.1.2
+            - 172.20.1.3
+            - 172.20.1.4
+        nodes:
+            - 172.20.1.2
+        ca: 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
+        crt: 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
+        key: LS0tLS1CRUdJTiBFRDI1NTE5IFBSSVZBVEUgS0VZLS0tLS0KTUM0Q0FRQXdCUVlESzJWd0JDSUVJQWhmdzFISzBKVFgzVjh2K09wZ2J5dXQ2VzN0OWhVaGczQW5pK043WTFTNAotLS0tLUVORCBFRDI1NTE5IFBSSVZBVEUgS0VZLS0tLS0K
+`,
+			expected: strings.TrimSpace(`
+Current context:     no-roles
+Nodes:               172.20.1.2
+Endpoints:           172.20.1.2, 172.20.1.3, 172.20.1.4
+Roles:               os:admin
+Certificate expires: 10 years from now (2031-07-03)
+`) + "\n",
+		},
+		{
+			name: "NoRoles",
+			config: `
+context: no-roles
+contexts:
+    no-roles:
+        endpoints:
+            - 172.20.1.2
+        ca: 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
+        crt: 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
+        key: LS0tLS1CRUdJTiBFRDI1NTE5IFBSSVZBVEUgS0VZLS0tLS0KTUM0Q0FRQXdCUVlESzJWd0JDSUVJREJybmN1UEV2RHFPRjhqWWJMNUxvNWhSUkZ2cXBPVWZud2RMOHRPdzdFRgotLS0tLUVORCBFRDI1NTE5IFBSSVZBVEUgS0VZLS0tLS0K
+`,
+			expected: strings.TrimSpace(`
+Current context:     no-roles
+Nodes:               not defined
+Endpoints:           172.20.1.2
+Roles:               not defined
+Certificate expires: 10 years from now (2031-07-03)
+`) + "\n",
+		},
+		{
+			name: "FutureRole",
+			config: `
+context: future-role
+contexts:
+    future-role:
+        ca: 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
+        crt: LS0tLS1CRUdJTiBDRVJUSUZJQ0FURS0tLS0tCk1JSUJNekNCNXFBREFnRUNBaEFQL1MrVGx0WTBHdGk5Q1g0UDNVZStNQVVHQXl0bGNEQVFNUTR3REFZRFZRUUsKRXdWMFlXeHZjekFlRncweU1UQTNNRFV4TVRRek1qRmFGdzB6TVRBM01ETXhNVFF6TWpGYU1CUXhFakFRQmdOVgpCQW9UQ1c5ek9tWjFkSFZ5WlRBcU1BVUdBeXRsY0FNaEFLck04NmtPYm1MdGw5OVdpdzFFL29pdnl2YXVqVmNkCmlQTk82TVhQNGxEMm8xSXdVREFPQmdOVkhROEJBZjhFQkFNQ0I0QXdIUVlEVlIwbEJCWXdGQVlJS3dZQkJRVUgKQXdFR0NDc0dBUVVGQndNQ01COEdBMVVkSXdRWU1CYUFGSEs3MXJqNU5ObFp3UnVWV3BXOG5DWm4rdmFsTUFVRwpBeXRsY0FOQkFDSno3NTlGeVFJMXlIWTJNRG9vZDNrZjdZeG9HRG1Hem1nNllqRHJueXAxWGpaQ3o1Q1RQbm9jCjhxWlAyTXE5MDJnOXZSSUh1dm84N0NIZjJacTNGZ1U9Ci0tLS0tRU5EIENFUlRJRklDQVRFLS0tLS0K
+        key: LS0tLS1CRUdJTiBFRDI1NTE5IFBSSVZBVEUgS0VZLS0tLS0KTUM0Q0FRQXdCUVlESzJWd0JDSUVJS1RCRDIyZDBLVnNTek5iSkNBdjNObUVnL1VWOTk4SHZvY2NGb1lDOEJ1bAotLS0tLUVORCBFRDI1NTE5IFBSSVZBVEUgS0VZLS0tLS0K
+`,
+			expected: strings.TrimSpace(`
+Current context:     future-role
+Nodes:               not defined
+Endpoints:           not defined
+Roles:               os:future
+Certificate expires: 10 years from now (2031-07-03)
+`) + "\n",
+		},
+	}
+
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			config, err := clientconfig.FromString(tc.config)
+			require.NoError(t, err)
+
+			actual, err := configInfoCommand(config, now)
+			assert.NoError(t, err)
+			assert.Equal(t, tc.expected, actual)
+		})
+	}
+}

website/content/docs/v0.11/Reference/cli.md

@@ -425,6 +425,33 @@ talosctl config endpoint <endpoint>... [flags]
 
 * [talosctl config](#talosctl-config)	 - Manage the client configuration file (talosconfig)
 
+## talosctl config info
+
+Show information about the current context
+
+```
+talosctl config info [flags]
+```
+
+### Options
+
+```
+  -h, --help   help for info
+```
+
+### Options inherited from parent commands
+
+```
+      --context string       Context to be used in command
+  -e, --endpoints strings    override default endpoints in Talos configuration
+  -n, --nodes strings        target the specified nodes
+      --talosconfig string   The path to the Talos configuration file (default "/home/user/.talos/config")
+```
+
+### SEE ALSO
+
+* [talosctl config](#talosctl-config)	 - Manage the client configuration file (talosconfig)
+
 ## talosctl config merge
 
 Merge additional contexts from another client configuration file
@@ -538,6 +565,7 @@ Manage the client configuration file (talosconfig)
 * [talosctl config context](#talosctl-config-context)	 - Set the current context
 * [talosctl config contexts](#talosctl-config-contexts)	 - List defined contexts
 * [talosctl config endpoint](#talosctl-config-endpoint)	 - Set the endpoint(s) for the current context
+* [talosctl config info](#talosctl-config-info)	 - Show information about the current context
 * [talosctl config merge](#talosctl-config-merge)	 - Merge additional contexts from another client configuration file
 * [talosctl config new](#talosctl-config-new)	 - Generate a new client configuration file
 * [talosctl config node](#talosctl-config-node)	 - Set the node(s) for the current context