Adding machine.service.internal dns entries (#123)

cmd/uncloud/machine/ls.go

@@ -46,7 +46,7 @@ func list(ctx context.Context, uncli *cli.CLI, clusterName string) error {
 	// Print the list of machines in a table format.
 	tw := tabwriter.NewWriter(os.Stdout, 0, 0, 3, ' ', 0)
 	// Print header.
-	if _, err = fmt.Fprintln(tw, "NAME\tSTATE\tADDRESS\tPUBLIC IP\tWIREGUARD ENDPOINTS"); err != nil {
+	if _, err = fmt.Fprintln(tw, "NAME\tSTATE\tADDRESS\tPUBLIC IP\tWIREGUARD ENDPOINTS\tMACHINE ID"); err != nil {
 		return fmt.Errorf("write header: %w", err)
 	}
 	// Print rows.
@@ -68,8 +68,8 @@ func list(ctx context.Context, uncli *cli.CLI, clusterName string) error {
 		}
 
 		if _, err = fmt.Fprintf(
-			tw, "%s\t%s\t%s\t%s\t%s\n", m.Name, capitalise(member.State.String()), subnet, publicIP,
-			strings.Join(endpoints, ", "),
+			tw, "%s\t%s\t%s\t%s\t%s\t%s\n", m.Name, capitalise(member.State.String()), subnet, publicIP,
+			strings.Join(endpoints, ", "), member.Machine.Id,
 		); err != nil {
 			return fmt.Errorf("write row: %w", err)
 		}

internal/machine/dns/resolver.go

@@ -91,6 +91,11 @@ func (r *ClusterResolver) updateServiceIPs(containers []store.ContainerRecord) {
 		newServiceIPs[ctr.ServiceName()] = append(newServiceIPs[ctr.ServiceName()], ip)
 		// Also add the service ID as a valid lookup.
 		newServiceIPs[ctr.ServiceID()] = append(newServiceIPs[ctr.ServiceID()], ip)
+
+		// Add <machine-id>.m.<service-name> as a lookup
+		serviceNameWithMachineID := record.MachineID + ".m." + ctr.ServiceName()
+		newServiceIPs[serviceNameWithMachineID] = append(newServiceIPs[serviceNameWithMachineID], ip)
+
 		containersCount++
 	}
 
@@ -99,7 +104,7 @@ func (r *ClusterResolver) updateServiceIPs(containers []store.ContainerRecord) {
 	r.serviceIPs = newServiceIPs
 	r.mu.Unlock()
 
-	r.log.Debug("DNS records updated.", "services", len(newServiceIPs)/2, "containers", containersCount)
+	r.log.Debug("DNS records updated.", "services", len(newServiceIPs)/3, "containers", containersCount)
 }
 
 // Resolve returns IP addresses of the service containers.

test/e2e/dns_test.go

@@ -0,0 +1,225 @@
+package e2e
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/docker/docker/api/types"
+	dockerclient "github.com/docker/docker/client"
+	"github.com/psviderski/uncloud/internal/ucind"
+	"github.com/psviderski/uncloud/pkg/api"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// TestInternalDNS tests the internal DNS functionality including the new machine-specific service lookups
+func TestInternalDNS(t *testing.T) {
+	t.Parallel()
+
+	clusterName := "ucind-test.dns"
+	ctx := context.Background()
+	c, _ := createTestCluster(t, clusterName, ucind.CreateClusterOptions{Machines: 3}, true)
+
+	cli, err := c.Machines[0].Connect(ctx)
+	require.NoError(t, err)
+
+	// Create a test service with multiple replicas across machines
+	serviceName := "test-dns-service"
+	t.Cleanup(func() {
+		err := cli.RemoveService(ctx, serviceName)
+		if err != nil && !strings.Contains(err.Error(), "not found") {
+			require.NoError(t, err)
+		}
+	})
+
+	// Deploy a service across all machines in global mode using pause container
+	spec := api.ServiceSpec{
+		Name: serviceName,
+		Mode: api.ServiceModeGlobal,
+		Container: api.ContainerSpec{
+			Image: "portainer/pause:latest",
+		},
+	}
+
+	deployment := cli.NewDeployment(spec, nil)
+	_, err = deployment.Run(ctx)
+	require.NoError(t, err)
+
+	// Wait for the service to be deployed
+	var svc api.Service
+	require.Eventually(t, func() bool {
+		svc, err = cli.InspectService(ctx, serviceName)
+		if err != nil {
+			return false
+		}
+		// Should have 3 containers (one per machine) and all should be running
+		if len(svc.Containers) != 3 {
+			return false
+		}
+		for _, ctr := range svc.Containers {
+			if ctr.Container.State.Status != "running" {
+				return false
+			}
+		}
+		return true
+	}, 30*time.Second, 1*time.Second, "Service should be deployed and running on all machines")
+
+	// Get Docker client to access ucind machine containers (shared across all DNS tests)
+	dockerCli, err := dockerclient.NewClientWithOpts(dockerclient.FromEnv, dockerclient.WithAPIVersionNegotiation())
+	require.NoError(t, err)
+
+	// Helper function to create DNS query service spec
+	createDNSQuerySpec := func(name, dnsQuery, outputFile string) api.ServiceSpec {
+		return api.ServiceSpec{
+			Name: name,
+			Mode: api.ServiceModeReplicated,
+			Container: api.ContainerSpec{
+				Image:   "wbitt/network-multitool",
+				Command: []string{"sh", "-c", fmt.Sprintf("nslookup %s > %s 2>&1 && echo 'DNS query completed' && sleep infinity", dnsQuery, outputFile)},
+				VolumeMounts: []api.VolumeMount{
+					{
+						VolumeName:    "host-tmp",
+						ContainerPath: "/tmp",
+					},
+				},
+			},
+			Volumes: []api.VolumeSpec{
+				{
+					Name: "host-tmp",
+					Type: "bind",
+					BindOptions: &api.BindOptions{
+						HostPath: "/tmp",
+					},
+				},
+			},
+			Replicas: 1,
+		}
+	}
+
+	// Helper function to run DNS query and get results
+	runDNSQuery := func(t *testing.T, serviceName, dnsQuery, outputFile string) string {
+		spec := createDNSQuerySpec(serviceName, dnsQuery, outputFile)
+
+		t.Cleanup(func() {
+			cli.RemoveService(ctx, spec.Name)
+		})
+
+		// Run the DNS query service
+		resp, err := cli.RunService(ctx, spec)
+		require.NoError(t, err)
+
+		// Wait for the DNS query to complete
+		var querySvc api.Service
+		require.Eventually(t, func() bool {
+			querySvc, err = cli.InspectService(ctx, resp.ID)
+			if err != nil || len(querySvc.Containers) == 0 {
+				return false
+			}
+			return querySvc.Containers[0].Container.State.Status == "running"
+		}, 30*time.Second, 1*time.Second, "DNS query container should be running")
+
+		// Give some time for DNS query to complete and write to file
+		time.Sleep(1 * time.Second)
+
+		// Find which ucind machine the DNS query container is running on
+		container := querySvc.Containers[0]
+		machineID := container.MachineID
+
+		// Get the ucind machine container name for this machine
+		var ucindMachineName string
+		for _, machine := range c.Machines {
+			if machine.ID == machineID {
+				ucindMachineName = machine.ContainerName
+				break
+			}
+		}
+		require.NotEmpty(t, ucindMachineName, "Should find ucind machine container name")
+
+		// Read the DNS results from the ucind machine's filesystem
+		exec, err := dockerCli.ContainerExecCreate(ctx, ucindMachineName, types.ExecConfig{
+			Cmd:          []string{"cat", outputFile},
+			AttachStdout: true,
+			AttachStderr: true,
+		})
+		require.NoError(t, err)
+
+		resp2, err := dockerCli.ContainerExecAttach(ctx, exec.ID, types.ExecStartCheck{})
+		require.NoError(t, err)
+		defer resp2.Close()
+
+		// Read the DNS output
+		buf := make([]byte, 4096)
+		n, _ := resp2.Reader.Read(buf)
+		return string(buf[:n])
+	}
+
+	// Helper function to verify DNS output doesn't contain errors
+	assertNoDNSErrors := func(t *testing.T, dnsOutput string) {
+		assert.NotContains(t, dnsOutput, "can't resolve", "DNS query should not contain resolution errors")
+		assert.NotContains(t, dnsOutput, "Name or service not known", "DNS query should not contain unknown service errors")
+	}
+
+	t.Run("service name resolves to all container IPs", func(t *testing.T) {
+		dnsOutput := runDNSQuery(t, "dns-test-service-name", serviceName+".internal", "/tmp/dns_result.txt")
+		t.Logf("DNS query output:\n%s", dnsOutput)
+
+		// Verify that all service container IPs are in the DNS response
+		for _, ctr := range svc.Containers {
+			containerIP := ctr.Container.UncloudNetworkIP().String()
+			assert.Contains(t, dnsOutput, containerIP,
+				"Service DNS should resolve to container IP %s", containerIP)
+		}
+
+		assertNoDNSErrors(t, dnsOutput)
+	})
+
+	t.Run("machine-specific service DNS lookups", func(t *testing.T) {
+		// Test the new <machine-id>.m.<service-name>.internal DNS feature
+		for i, targetContainer := range svc.Containers {
+			targetMachineID := targetContainer.MachineID
+			targetContainerIP := targetContainer.Container.UncloudNetworkIP().String()
+
+			// Construct the machine-specific DNS name
+			machineSpecificDNS := targetMachineID + ".m." + serviceName + ".internal"
+			outputFile := fmt.Sprintf("/tmp/dns_result_machine_%d.txt", i)
+
+			dnsOutput := runDNSQuery(t, fmt.Sprintf("dns-test-machine-%d", i), machineSpecificDNS, outputFile)
+			t.Logf("Machine-specific DNS query output for %s:\n%s", machineSpecificDNS, dnsOutput)
+
+			// Verify that the specific container IP is returned
+			assert.Contains(t, dnsOutput, targetContainerIP,
+				"Machine-specific DNS %s should resolve to container IP %s",
+				machineSpecificDNS, targetContainerIP)
+
+			// Verify that other container IPs are not returned (machine-specific should return only one IP)
+			for _, ctr := range svc.Containers {
+				if ctr.MachineID != targetMachineID {
+					otherContainerIP := ctr.Container.UncloudNetworkIP().String()
+					assert.NotContains(t, dnsOutput, otherContainerIP,
+						"Machine-specific DNS %s should not resolve to other container IP %s",
+						machineSpecificDNS, otherContainerIP)
+				}
+			}
+
+			assertNoDNSErrors(t, dnsOutput)
+		}
+	})
+
+	t.Run("service ID DNS lookup", func(t *testing.T) {
+		// Test that service ID also resolves (existing functionality)
+		dnsOutput := runDNSQuery(t, "dns-test-service-id", svc.ID+".internal", "/tmp/dns_result_service_id.txt")
+		t.Logf("Service ID DNS query output:\n%s", dnsOutput)
+
+		// Verify that all service container IPs are in the DNS response
+		for _, ctr := range svc.Containers {
+			containerIP := ctr.Container.UncloudNetworkIP().String()
+			assert.Contains(t, dnsOutput, containerIP,
+				"Service ID DNS should resolve to container IP %s", containerIP)
+		}
+
+		assertNoDNSErrors(t, dnsOutput)
+	})
+}