Exported services CLI and docs

[tauhid621]

Description

This PR adds a new cli command to list exported services

command: consul services exported-services

The PR also adds the API docs for the exported services API.

CLI output
CE

$ ./bin/consul services exported-services                          
Service   Consumer Peers
backend   east, west
db        west
frontend  east, east-eu
web       east

Enterprise

$ ./bin/consul services exported-services                          
Service   Partition  Namespace  Consumer Peers  Consumer Partitions
backend   default    default    east, west      
db        default    default    west            partition-west
frontend  default    default    east, east-eu   
frontend  default    ns         east, east-eu   
web       default    default    east 

CLI output json

$ ./bin/consul services exported-services -format=json
[
    {
        "Service": "backend",
        "Consumers": {
            "Peers": [
                "east",
                "west"
            ]
        }
    },
    {
        "Service": "db",
        "Consumers": {
            "Peers": [
                "west"
            ]
        }
    },
    {
        "Service": "frontend",
        "Consumers": {
            "Peers": [
                "east",
                "east-eu"
            ]
        }
    },
    {
        "Service": "web",
        "Consumers": {
            "Peers": [
                "east"
            ]
        }
    }
]

Testing & Reproduction steps

• Tests added
• Manual testing

Links

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

[absolutelightning]

@tauhid621 I feel json structure is taking too much space and increased number of lines. We should also give user a table view option in the command. Please see the following json structure -

[
    {
        "Service": "consul",
        "Consumers": {
            "Peers": [
                "consul"
            ]
        }
    },
    {
        "Service": "batman",
        "Consumers": {
            "Peers": [
                "superman"
            ]
        }
    },
    {
        "Service": "service1",
        "Partition": "part",
        "Consumers": {
            "Peers": [
                "superman",
                "heman"
            ],
            "Partitions": [
                "part1",
                "part2"
            ]
        }
    },
    {
        "Service": "service1",
        "Partition": "part",
        "Consumers": {
            "Peers": [
                "superman",
                "heman"
            ],
            "Partitions": [
                "part1",
                "part2"
            ]
        }
    },
    {
        "Service": "service1",
        "Partition": "part",
        "Consumers": {
            "Peers": [
                "superman",
                "heman"
            ],
            "Partitions": [
                "part1",
                "part2"
            ]
        }
    }
]

Comparing this to table structure - it feels concise.

Service 	Partition	Namespace	Consumers
consul  	         	         	Peer(consul)
batman  	         	         	Peer(superman)
service1	part     	         	Peer(superman)
service1	part     	         	Peer(heman)
service1	part     	         	Partition(part1)
service1	part     	         	Partition(part2)
service1	part     	         	Peer(superman)
service1	part     	         	Peer(heman)
service1	part     	         	Partition(part1)
service1	part     	         	Partition(part2)
service1	part     	         	Peer(superman)
service1	part     	         	Peer(heman)
service1	part     	         	Partition(part1)
service1	part     	         	Partition(part2)

Here is a patch for the same -

diff --git a/api/exported_services.go b/api/exported_services.go
index 50483e9c8d..9a45d2104a 100644
--- a/api/exported_services.go
+++ b/api/exported_services.go
@@ -44,6 +44,6 @@ func (c *Client) ExportedServices(q *QueryOptions) ([]ResolvedExportedService, *
 	if err := decodeBody(resp, &expSvcs); err != nil {
 		return nil, nil, err
 	}
-
+
 	return expSvcs, qm, nil
 }
diff --git a/command/exportedservices/exported_services.go b/command/exportedservices/exported_services.go
index c63af8d771..27394b447d 100644
--- a/command/exportedservices/exported_services.go
+++ b/command/exportedservices/exported_services.go
@@ -7,9 +7,8 @@ import (
 	"encoding/json"
 	"flag"
 	"fmt"
-
+	"github.com/hashicorp/consul/command/cli"
 	"github.com/hashicorp/consul/command/flags"
-	"github.com/mitchellh/cli"
 )

 func New(ui cli.Ui) *cmd {
@@ -23,6 +22,7 @@ type cmd struct {
 	flags *flag.FlagSet
 	http  *flags.HTTPFlags
 	help  string
+	table bool
 }

 func (c *cmd) init() {
@@ -31,6 +31,7 @@ func (c *cmd) init() {
 	flags.Merge(c.flags, c.http.ClientFlags())
 	flags.Merge(c.flags, c.http.ServerFlags())
 	flags.Merge(c.flags, c.http.PartitionFlag())
+	c.flags.BoolVar(&c.table, "table", false, "Output in table format")
 	c.help = flags.Usage(help, c.flags)
 }

@@ -51,6 +52,25 @@ func (c *cmd) Run(args []string) int {
 		return 1
 	}

+	if len(exportedServices) == 0 {
+		c.UI.Info("No exported services found")
+		return 0
+	}
+
+	if c.table {
+		tbl := cli.NewTable("Service", "Partition", "Namespace", "Consumers")
+		for _, expService := range exportedServices {
+			for _, peer := range expService.Consumers.Peers {
+				tbl.AddRow([]string{expService.Service, expService.Partition, expService.Namespace, fmt.Sprintf("Peer(%s)", peer)}, []string{})
+			}
+			for _, partition := range expService.Consumers.Partitions {
+				tbl.AddRow([]string{expService.Service, expService.Partition, expService.Namespace, fmt.Sprintf("Partition(%s)", partition)}, []string{})
+			}
+		}
+		c.UI.Table(tbl)
+		return 0
+	}
+
 	b, err := json.MarshalIndent(exportedServices, "", "    ")
 	if err != nil {
 		c.UI.Error("Failed to encode output data")
diff --git a/command/exportedservices/exported_services_test.go b/command/exportedservices/exported_services_test.go
index 23ad13b678..83751ef266 100644
--- a/command/exportedservices/exported_services_test.go
+++ b/command/exportedservices/exported_services_test.go
@@ -79,4 +79,5 @@ func TestExportedServices(t *testing.T) {
 	require.Equal(t, "db", resp[0].Service)
 	require.Equal(t, "web", resp[1].Service)
 	require.Equal(t, []string{"east", "west"}, resp[0].Consumers.Peers)
+	require.Equal(t, []string{"east", "west"}, resp[1].Consumers.Peers)
 }

[tauhid621]

@absolutelightning Updated the code to have two format options. This is similar to other cli commands
The default command prints the table version. I also had to use mitchellh/cli as it was difficult to test with the cli tool which you used.

[absolutelightning]

LGTM 🚀

[boruszak]

I reviewed the docs edits for the API and CLI command. Please implement the suggested changes.

Approving on behalf of consul-docs

[hc-github-team-consul-core]

Backport failed @tauhid621. Run: https://github.com/hashicorp/consul/actions/runs/7794306924