Initial work on shared node integration test

This commit adds initial integration tests for shared nodes, it adds
them and verifies that they are shared.

It does not yet manage to ping the shared node because it does not seem
to establish the connection.

integration_test.go

@@ -446,6 +446,89 @@ func (s *IntegrationTestSuite) TestPingAllPeers() {
 	}
 }
 
+func (s *IntegrationTestSuite) TestSharedNodes() {
+	main := s.namespaces["main"]
+	shared := s.namespaces["shared"]
+
+	result, err := executeCommand(
+		&headscale,
+		[]string{"headscale", "nodes", "list", "-o", "json", "--namespace", "shared"},
+	)
+	assert.Nil(s.T(), err)
+
+	var machineList []Machine
+	err = json.Unmarshal([]byte(result), &machineList)
+	assert.Nil(s.T(), err)
+
+	for _, machine := range machineList {
+
+		result, err := executeCommand(
+			&headscale,
+			[]string{"headscale", "nodes", "share", "--namespace", "shared", fmt.Sprint(machine.ID), "main"},
+		)
+		assert.Nil(s.T(), err)
+
+		fmt.Println("Shared node with result: ", result)
+	}
+
+	result, err = executeCommand(
+		&headscale,
+		[]string{"headscale", "nodes", "list", "--namespace", "main"},
+	)
+	assert.Nil(s.T(), err)
+	fmt.Println("Nodelist after sharing", result)
+
+	// Chck that the correct count of host is present in node list
+	lines := strings.Split(result, "\n")
+	assert.Equal(s.T(), len(main.tailscales)+len(shared.tailscales), len(lines)-2)
+
+	for hostname := range main.tailscales {
+		assert.Contains(s.T(), result, hostname)
+	}
+
+	for hostname := range shared.tailscales {
+		assert.Contains(s.T(), result, hostname)
+	}
+
+	// TODO(kradalby): Figure out why these connections are not set up
+	// // TODO: See if we can have a more deterministic wait here.
+	// time.Sleep(100 * time.Second)
+
+	// mainIps, err := getIPs(main.tailscales)
+	// assert.Nil(s.T(), err)
+
+	// sharedIps, err := getIPs(shared.tailscales)
+	// assert.Nil(s.T(), err)
+
+	// for hostname, tailscale := range main.tailscales {
+	// 	for peername, ip := range sharedIps {
+	// 		s.T().Run(fmt.Sprintf("%s-%s", hostname, peername), func(t *testing.T) {
+	// 			// We currently cant ping ourselves, so skip that.
+	// 			if peername != hostname {
+	// 				// We are only interested in "direct ping" which means what we
+	// 				// might need a couple of more attempts before reaching the node.
+	// 				command := []string{
+	// 					"tailscale", "ping",
+	// 					"--timeout=1s",
+	// 					"--c=20",
+	// 					"--until-direct=true",
+	// 					ip.String(),
+	// 				}
+
+	// 				fmt.Printf("Pinging from %s (%s) to %s (%s)\n", hostname, mainIps[hostname], peername, ip)
+	// 				result, err := executeCommand(
+	// 					&tailscale,
+	// 					command,
+	// 				)
+	// 				assert.Nil(t, err)
+	// 				fmt.Printf("Result for %s: %s\n", hostname, result)
+	// 				assert.Contains(t, result, "pong")
+	// 			}
+	// 		})
+	// 	}
+	// }
+}
+
 func getIPs(tailscales map[string]dockertest.Resource) (map[string]netaddr.IP, error) {
 	ips := make(map[string]netaddr.IP)
 	for hostname, tailscale := range tailscales {