feat: net list

Author: Alonza0314

cmd/net.go

@@ -46,15 +46,15 @@ func netFunc(cmd *cobra.Command, args []string) {
 			}
 		}
 	case "list":
-		// if len(args) != 2 {
-		// 	errFormat(args)
-		// } else {
-		// 	if list, err := veth.List(); err != nil {
-		// 		errPrint(err)
-		// 	} else {
-		// 		fmt.Print(list)
-		// 	}
-		// }
+		if len(args) != 2 {
+			errFormat(args)
+		} else {
+			if list, err := veth.List(args[1]); err != nil {
+				errPrint(err)
+			} else {
+				fmt.Print(list)
+			}
+		}
 	case "set-ip":
 	case "up":
 	case "down:":

integration-test/veth/list_test_1_lo.txt

@@ -0,0 +1,5 @@
+┌──────────────────┬─────┬──────────────────┬─────────────────┐
+│IFACE             │STATE│IP                │MAC              │
+├──────────────────┼─────┼──────────────────┼─────────────────┤
+│lo                │down │-                 │-                │
+└──────────────────┴─────┴──────────────────┴─────────────────┘

integration-test/veth/test.sh

@@ -26,6 +26,13 @@ cleanup_two_namespace() {
     ../nsctl ns delete test-2
 }
 
+list_test_1_lo() {
+    output=$(../nsctl net list test-1)
+    expect=$(cat list_test_1_lo.txt)
+
+    diff "List test 1 lo" "$output" "$expect"
+}
+
 connect_test() {
     output=$(../nsctl net connect test-1 test-2)
     expect=$(cat connect_test.txt)
@@ -50,6 +57,7 @@ disconnect_test() {
 main() {
     setup_two_namespace
 
+    list_test_1_lo
     connect_test
     connect_test_error
     disconnect_test

veth/list.go

@@ -0,0 +1,86 @@
+package veth
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/Alonza0314/nsctl/namespace"
+	"github.com/vishvananda/netlink"
+	"github.com/vishvananda/netns"
+)
+
+func List(ns string) (string, error) {
+	_, originCloseFunc, err := namespace.GetOriginNs()
+	if err != nil {
+		return "", err
+	}
+	defer originCloseFunc()
+
+	targetNsFd, targetNsCloseFunc, err := namespace.GetNsFd(ns)
+	if err != nil {
+		return "", fmt.Errorf("failed to namespace %s file descriptor: %v", ns, err)
+	}
+	defer targetNsCloseFunc()
+
+	if err := netns.Set(targetNsFd); err != nil {
+		return "", fmt.Errorf("failed to set to namespace %s: %v", ns, err)
+	}
+
+	links, err := netlink.LinkList()
+	if err != nil {
+		return "", fmt.Errorf("failed to get net links in namespace %s: %v", ns, err)
+	}
+
+	return printTable(links), nil
+}
+
+func printTable(links []netlink.Link) string {
+	var b strings.Builder
+
+	ifWidth, stateWidth, ipWidth, macWidth := 18, 5, 18, 17
+
+	b.WriteString("┌" + strings.Repeat("─", ifWidth) + "┬" + strings.Repeat("─", stateWidth) + "┬" + strings.Repeat("─", ipWidth) + "┬" + strings.Repeat("─", macWidth) + "┐\n")
+	b.WriteString(fmt.Sprintf("│%-*.*s│%-*.*s│%-*.*s│%-*.*s│\n", ifWidth, ifWidth, "IFACE", stateWidth, stateWidth, "STATE", ipWidth, ipWidth, "IP", macWidth, macWidth, "MAC"))
+	b.WriteString("├" + strings.Repeat("─", ifWidth) + "┼" + strings.Repeat("─", stateWidth) + "┼" + strings.Repeat("─", ipWidth) + "┼" + strings.Repeat("─", macWidth) + "┤\n")
+
+	for _, link := range links {
+		attrs := link.Attrs()
+		if attrs == nil {
+			continue
+		}
+
+		if attrs.Name == "gre0" || attrs.Name == "gretap0" || attrs.Name == "erspan0" || attrs.Name == "ip6gre0" || attrs.Name == "ip6gretap0" {
+			continue
+		}
+
+		state := attrs.OperState.String()
+		if state == "" {
+			state = "-"
+		}
+
+		ip := "-"
+		if addrs, err := netlink.AddrList(link, netlink.FAMILY_ALL); err == nil && len(addrs) > 0 {
+			ipList := make([]string, 0, len(addrs))
+			for _, addr := range addrs {
+				if addr.IPNet != nil {
+					ipList = append(ipList, addr.IPNet.IP.String())
+				}
+			}
+			if len(ipList) > 0 {
+				ip = strings.Join(ipList, ",")
+			}
+		}
+
+		mac := attrs.HardwareAddr.String()
+		if mac == "" {
+			mac = "-"
+		}
+
+		b.WriteString(fmt.Sprintf("│%-*.*s│%-*.*s│%-*.*s│%-*.*s│\n", ifWidth, ifWidth, attrs.Name, stateWidth, stateWidth, state, ipWidth, ipWidth, ip, macWidth, macWidth, mac))
+
+	}
+
+	b.WriteString("└" + strings.Repeat("─", ifWidth) + "┴" + strings.Repeat("─", stateWidth) + "┴" + strings.Repeat("─", ipWidth) + "┴" + strings.Repeat("─", macWidth) + "┘\n")
+
+	return b.String()
+}