cli: Add consul intention list command (based on PR #6825)

.changelog/9468.txt

@@ -0,0 +1,3 @@
+```release-note:feature
+cli: The `consul intention` command now has a new `list` subcommand to allow the listing of configured intentions. It also supports the `-namespace=` option.
+```

command/commands_oss.go

@@ -64,6 +64,7 @@ import (
 	ixncreate "github.com/hashicorp/consul/command/intention/create"
 	ixndelete "github.com/hashicorp/consul/command/intention/delete"
 	ixnget "github.com/hashicorp/consul/command/intention/get"
+	ixnlist "github.com/hashicorp/consul/command/intention/list"
 	ixnmatch "github.com/hashicorp/consul/command/intention/match"
 	"github.com/hashicorp/consul/command/join"
 	"github.com/hashicorp/consul/command/keygen"
@@ -182,6 +183,7 @@ func init() {
 	Register("intention create", func(ui cli.Ui) (cli.Command, error) { return ixncreate.New(ui), nil })
 	Register("intention delete", func(ui cli.Ui) (cli.Command, error) { return ixndelete.New(ui), nil })
 	Register("intention get", func(ui cli.Ui) (cli.Command, error) { return ixnget.New(ui), nil })
+	Register("intention list", func(ui cli.Ui) (cli.Command, error) { return ixnlist.New(ui), nil })
 	Register("intention match", func(ui cli.Ui) (cli.Command, error) { return ixnmatch.New(ui), nil })
 	Register("join", func(ui cli.Ui) (cli.Command, error) { return join.New(ui), nil })
 	Register("keygen", func(ui cli.Ui) (cli.Command, error) { return keygen.New(ui), nil })

command/intention/intention.go

@@ -40,6 +40,10 @@ Usage: consul intention <subcommand> [options] [args]
 
       $ consul intention check web db
 
+  List all intentions:
+
+      $ consul intention list
+
   Find all intentions for communicating to the "db" service:
 
       $ consul intention match db

command/intention/list/intention_list.go

@@ -0,0 +1,85 @@
+package list
+
+import (
+	"flag"
+	"fmt"
+
+	"github.com/hashicorp/consul/command/flags"
+	"github.com/mitchellh/cli"
+	"github.com/ryanuber/columnize"
+)
+
+func New(ui cli.Ui) *cmd {
+	c := &cmd{UI: ui}
+	c.init()
+	return c
+}
+
+type cmd struct {
+	UI    cli.Ui
+	flags *flag.FlagSet
+	http  *flags.HTTPFlags
+	help  string
+}
+
+func (c *cmd) init() {
+	c.flags = flag.NewFlagSet("", flag.ContinueOnError)
+
+	c.http = &flags.HTTPFlags{}
+	flags.Merge(c.flags, c.http.ClientFlags())
+	flags.Merge(c.flags, c.http.ServerFlags())
+	flags.Merge(c.flags, c.http.NamespaceFlags())
+	c.help = flags.Usage(help, c.flags)
+}
+
+func (c *cmd) Run(args []string) int {
+	if err := c.flags.Parse(args); err != nil {
+		return 1
+	}
+
+	client, err := c.http.APIClient()
+	if err != nil {
+		c.UI.Error(fmt.Sprintf("Error connecting to Consul agent: %s", err))
+		return 1
+	}
+
+	ixns, _, err := client.Connect().Intentions(nil)
+	if err != nil {
+		c.UI.Error(fmt.Sprintf("Failed to retrieve the intentions list: %s", err))
+		return 1
+	}
+
+	if len(ixns) == 0 {
+		c.UI.Error(fmt.Sprintf("There are no intentions."))
+		return 2
+	}
+
+	result := make([]string, 0, len(ixns))
+	header := "ID\x1fSource\x1fAction\x1fDestination\x1fPrecedence"
+	result = append(result, header)
+	for _, ixn := range ixns {
+		line := fmt.Sprintf("%s\x1f%s\x1f%s\x1f%s\x1f%d",
+			ixn.ID, ixn.SourceName, ixn.Action, ixn.DestinationName, ixn.Precedence)
+		result = append(result, line)
+	}
+
+	output := columnize.Format(result, &columnize.Config{Delim: string([]byte{0x1f})})
+	c.UI.Output(output)
+
+	return 0
+}
+
+func (c *cmd) Synopsis() string {
+	return synopsis
+}
+
+func (c *cmd) Help() string {
+	return c.help
+}
+
+const synopsis = "List intentions."
+const help = `
+Usage: consul intention list
+
+  List all intentions.
+`

command/intention/list/intention_list_test.go

@@ -0,0 +1,47 @@
+package list
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/hashicorp/consul/agent"
+	"github.com/hashicorp/consul/api"
+	"github.com/mitchellh/cli"
+	"github.com/stretchr/testify/require"
+)
+
+func TestIntentionListCommand_noTabs(t *testing.T) {
+	t.Parallel()
+	if strings.ContainsRune(New(cli.NewMockUi()).Help(), '\t') {
+		t.Fatal("help has tabs")
+	}
+}
+
+func TestIntentionListCommand(t *testing.T) {
+	t.Parallel()
+	require := require.New(t)
+	a := agent.NewTestAgent(t, ``)
+	defer a.Shutdown()
+	client := a.Client()
+
+	// Create the intention
+	var id string
+	{
+		var err error
+		//nolint:staticcheck
+		id, _, err = client.Connect().IntentionCreate(&api.Intention{
+			SourceName:      "web",
+			DestinationName: "db",
+			Action:          api.IntentionActionAllow,
+		}, nil)
+		require.NoError(err)
+	}
+
+	// List all intentions
+	ui := cli.NewMockUi()
+	cmd := New(ui)
+	args := []string{"-http-addr=" + a.HTTPAddr()}
+
+	require.Equal(0, cmd.Run(args), ui.ErrorWriter.String())
+	require.Contains(ui.OutputWriter.String(), id)
+}

website/content/commands/intention/index.mdx

@@ -22,8 +22,8 @@ API](/api/connect/intentions).
 
 Usage: `consul intention <subcommand>`
 
-For the exact documentation for your Consul version, run `consul intention -h` to view
-the complete list of subcommands.
+For the exact documentation for your Consul version, run `consul intention -h`
+to view the complete list of subcommands.
 
 ```text
 Usage: consul intention <subcommand> [options] [args]
@@ -34,6 +34,7 @@ Subcommands:
     check     Check whether a connection between two services is allowed.
     create    Create intentions for service connections.
     delete    Delete an intention.
+    list      Lists all intentions.
     get       Show information about an intention.
     match     Show intentions that match a source or destination.
 ```
@@ -62,6 +63,12 @@ Test whether a "web" is allowed to connect to "db":
 $ consul intention check web db
 ```
 
+List all intentions:
+
+```shell-session
+$ consul intention list
+```
+
 Find all intentions for communicating to the "db" service:
 
 ```shell-session

website/content/commands/intention/list.mdx

@@ -0,0 +1,34 @@
+---
+layout: commands
+page_title: 'Commands: Intention List'
+sidebar_title: list
+---
+
+# Consul Intention List
+
+Command: `consul intention list`
+
+The `intention list` command shows all intentions including ID and precedence.
+
+## Usage
+
+Usage:
+
+- `consul intention list`
+
+#### API Options
+
+@include 'http_api_options_client.mdx'
+
+#### Enterprise Options
+
+@include 'http_api_namespace_options.mdx'
+
+## Examples
+
+```shell-session
+$ consul intention list
+ID                                    Source     Action  Destination  Precedence
+                                      web        allow   db           9
+36a6cf15-5f0e-a388-163e-0f608009704a  dashboard  allow   counting     9
+```