fix: tries to reconnect of remote host disconnects (#2876)

assets/auto-imports.d.ts

@@ -230,6 +230,7 @@ declare global {
   const useGamepad: typeof import('@vueuse/core')['useGamepad']
   const useGeolocation: typeof import('@vueuse/core')['useGeolocation']
   const useHead: typeof import('@vueuse/head')['useHead']
+  const useHosts: typeof import('./stores/hosts')['useHosts']
   const useI18n: typeof import('vue-i18n')['useI18n']
   const useIdle: typeof import('@vueuse/core')['useIdle']
   const useImage: typeof import('@vueuse/core')['useImage']
@@ -587,6 +588,7 @@ declare module 'vue' {
     readonly useGamepad: UnwrapRef<typeof import('@vueuse/core')['useGamepad']>
     readonly useGeolocation: UnwrapRef<typeof import('@vueuse/core')['useGeolocation']>
     readonly useHead: UnwrapRef<typeof import('@vueuse/head')['useHead']>
+    readonly useHosts: UnwrapRef<typeof import('./stores/hosts')['useHosts']>
     readonly useI18n: UnwrapRef<typeof import('vue-i18n')['useI18n']>
     readonly useIdle: UnwrapRef<typeof import('@vueuse/core')['useIdle']>
     readonly useImage: UnwrapRef<typeof import('@vueuse/core')['useImage']>
@@ -937,6 +939,7 @@ declare module '@vue/runtime-core' {
     readonly useGamepad: UnwrapRef<typeof import('@vueuse/core')['useGamepad']>
     readonly useGeolocation: UnwrapRef<typeof import('@vueuse/core')['useGeolocation']>
     readonly useHead: UnwrapRef<typeof import('@vueuse/head')['useHead']>
+    readonly useHosts: UnwrapRef<typeof import('./stores/hosts')['useHosts']>
     readonly useI18n: UnwrapRef<typeof import('vue-i18n')['useI18n']>
     readonly useIdle: UnwrapRef<typeof import('@vueuse/core')['useIdle']>
     readonly useImage: UnwrapRef<typeof import('@vueuse/core')['useImage']>

assets/components/SideMenu.vue

@@ -10,10 +10,11 @@
     </div>
     <transition :name="sessionHost ? 'slide-left' : 'slide-right'" mode="out-in">
       <ul class="menu p-0" v-if="!sessionHost">
-        <li v-for="host in config.hosts">
-          <a @click.prevent="setHost(host.id)">
+        <li v-for="host in hosts">
+          <a @click.prevent="setHost(host.id)" :class="{ 'pointer-events-none text-base-content/50': !host.available }">
             <ph:computer-tower />
             {{ host.name }}
+            <span class="badge badge-error badge-xs p-1.5" v-if="!host.available">offline</span>
           </a>
         </li>
       </ul>
@@ -68,6 +69,7 @@ import { sessionHost } from "@/composable/storage";
 const store = useContainerStore();
 
 const { activeContainers, visibleContainers, ready } = storeToRefs(store);
+const { hosts } = useHosts();
 
 function setHost(host: string | null) {
   sessionHost.value = host;
@@ -116,16 +118,6 @@ const menuItems = computed(() => {
   }
 });
 
-const hosts = computed(() =>
-  config.hosts.reduce(
-    (acc, item) => {
-      acc[item.id] = item;
-      return acc;
-    },
-    {} as Record<string, { name: string; id: string }>,
-  ),
-);
-
 const activeContainersById = computed(() =>
   activeContainers.value.reduce(
     (acc, item) => {

assets/stores/container.ts

@@ -5,6 +5,7 @@ import { Container } from "@/models/Container";
 import i18n from "@/modules/i18n";
 
 const { showToast } = useToast();
+const { markHostAvailable } = useHosts();
 // @ts-ignore
 const { t } = i18n.global;
 
@@ -68,6 +69,11 @@ export const useContainerStore = defineStore("container", () => {
       }
     });
 
+    es.addEventListener("host-unavailable", (e) => {
+      const hostId = (e as MessageEvent).data;
+      markHostAvailable(hostId, false);
+    });
+
     es.addEventListener("container-health", (e) => {
       const event = JSON.parse((e as MessageEvent).data) as { actorId: string; health: ContainerHealth };
       const container = allContainersById.value[event.actorId];

assets/stores/hosts.ts

@@ -0,0 +1,25 @@
+type Host = {
+  name: string;
+  id: string;
+  available: boolean;
+};
+const hosts = computed(() =>
+  config.hosts.reduce(
+    (acc, item) => {
+      acc[item.id] = { ...item, available: true };
+      return acc;
+    },
+    {} as Record<string, Host>,
+  ),
+);
+
+const markHostAvailable = (id: string, available: boolean) => {
+  hosts.value[id].available = available;
+};
+
+export function useHosts() {
+  return {
+    hosts,
+    markHostAvailable,
+  };
+}

docker-compose.yml

@@ -44,7 +44,8 @@ services:
     build:
       context: .
     depends_on:
-      - proxy
+      proxy:
+        condition: service_healthy
 
   proxy:
     container_name: proxy
@@ -53,6 +54,11 @@ services:
       - /var/run/docker.sock:/var/run/docker.sock:ro
     environment:
       - CONTAINERS=1
+    healthcheck:
+      test: ["CMD", "nc", "-z", "127.0.0.1", "2375"]
+      interval: 30s
+      retries: 5
+      start_period: 5s
     ports:
       - 2375:2375
 

internal/docker/client.go

@@ -61,7 +61,7 @@ type Client interface {
 	ListContainers() ([]Container, error)
 	FindContainer(string) (Container, error)
 	ContainerLogs(context.Context, string, string, StdType) (io.ReadCloser, error)
-	Events(context.Context, chan<- ContainerEvent) <-chan error
+	Events(context.Context, chan<- ContainerEvent) error
 	ContainerLogsBetweenDates(context.Context, string, time.Time, time.Time, StdType) (io.ReadCloser, error)
 	ContainerStats(context.Context, string, chan<- ContainerStat) error
 	Ping(context.Context) (types.Ping, error)
@@ -297,23 +297,17 @@ func (d *_client) ContainerLogs(ctx context.Context, id string, since string, st
 	return reader, nil
 }
 
-func (d *_client) Events(ctx context.Context, messages chan<- ContainerEvent) <-chan error {
-	dockerMessages, errors := d.cli.Events(ctx, types.EventsOptions{})
-
-	go func() {
+func (d *_client) Events(ctx context.Context, messages chan<- ContainerEvent) error {
+	dockerMessages, err := d.cli.Events(ctx, types.EventsOptions{})
 
 	for {
 		select {
 		case <-ctx.Done():
-				return
-			case err := <-errors:
-				log.Fatalf("error while listening to docker events: %v. Exiting...", err)
-			case message, ok := <-dockerMessages:
-				if !ok {
-					log.Errorf("docker events channel closed")
-					return
-				}
+			return nil
+		case err := <-err:
+			return err
 
+		case message := <-dockerMessages:
 			if message.Type == "container" && len(message.Actor.ID) > 0 {
 				messages <- ContainerEvent{
 					ActorID: message.Actor.ID[:12],
@@ -323,9 +317,7 @@ func (d *_client) Events(ctx context.Context, messages chan<- ContainerEvent) <-
 			}
 		}
 	}
-	}()
 
-	return errors
 }
 
 func (d *_client) ContainerLogsBetweenDates(ctx context.Context, id string, from time.Time, to time.Time, stdType StdType) (io.ReadCloser, error) {

internal/docker/container_store.go

@@ -2,7 +2,9 @@ package docker
 
 import (
 	"context"
+	"errors"
 	"sync"
+	"sync/atomic"
 
 	"github.com/puzpuzpuz/xsync/v3"
 	log "github.com/sirupsen/logrus"
@@ -14,6 +16,9 @@ type ContainerStore struct {
 	client         Client
 	statsCollector *StatsCollector
 	wg             sync.WaitGroup
+	connected      atomic.Bool
+	events         chan ContainerEvent
+	ctx            context.Context
 }
 
 func NewContainerStore(ctx context.Context, client Client) *ContainerStore {
@@ -23,24 +28,54 @@ func NewContainerStore(ctx context.Context, client Client) *ContainerStore {
 		subscribers:    xsync.NewMapOf[context.Context, chan ContainerEvent](),
 		statsCollector: NewStatsCollector(client),
 		wg:             sync.WaitGroup{},
+		events:         make(chan ContainerEvent),
+		ctx:            ctx,
 	}
 
 	s.wg.Add(1)
 
-	go s.init(ctx)
+	go s.init()
 
 	return s
 }
 
-func (s *ContainerStore) List() []Container {
+func (s *ContainerStore) checkConnectivity() error {
+	if s.connected.CompareAndSwap(false, true) {
+		go func() {
+			log.Debugf("subscribing to docker events from container store %s", s.client.Host())
+			err := s.client.Events(s.ctx, s.events)
+			if !errors.Is(err, context.Canceled) {
+				log.Errorf("docker store unexpectedly disconnected from docker events from %s with %v", s.client.Host(), err)
+			}
+			s.connected.Store(false)
+		}()
+
+		if containers, err := s.client.ListContainers(); err != nil {
+			return err
+		} else {
+			s.containers.Clear()
+			for _, c := range containers {
+				s.containers.Store(c.ID, &c)
+			}
+		}
+	}
+
+	return nil
+}
+
+func (s *ContainerStore) List() ([]Container, error) {
 	s.wg.Wait()
+
+	if err := s.checkConnectivity(); err != nil {
+		return nil, err
+	}
 	containers := make([]Container, 0)
 	s.containers.Range(func(_ string, c *Container) bool {
 		containers = append(containers, *c)
 		return true
 	})
 
-	return containers
+	return containers, nil
 }
 
 func (s *ContainerStore) Client() Client {
@@ -49,7 +84,7 @@ func (s *ContainerStore) Client() Client {
 
 func (s *ContainerStore) Subscribe(ctx context.Context, events chan ContainerEvent) {
 	go func() {
-		if s.statsCollector.Start(context.Background()) {
+		if s.statsCollector.Start(s.ctx) {
 			log.Debug("clearing container stats as stats collector has been stopped")
 			s.containers.Range(func(_ string, c *Container) bool {
 				c.Stats.Clear()
@@ -57,6 +92,7 @@ func (s *ContainerStore) Subscribe(ctx context.Context, events chan ContainerEve
 			})
 		}
 	}()
+
 	s.subscribers.Store(ctx, events)
 }
 
@@ -69,26 +105,17 @@ func (s *ContainerStore) SubscribeStats(ctx context.Context, stats chan Containe
 	s.statsCollector.Subscribe(ctx, stats)
 }
 
-func (s *ContainerStore) init(ctx context.Context) {
-	events := make(chan ContainerEvent)
-	s.client.Events(ctx, events)
-
+func (s *ContainerStore) init() {
 	stats := make(chan ContainerStat)
-	s.statsCollector.Subscribe(ctx, stats)
+	s.statsCollector.Subscribe(s.ctx, stats)
 
-	if containers, err := s.client.ListContainers(); err == nil {
-		for _, c := range containers {
-			s.containers.Store(c.ID, &c)
-		}
-	} else {
-		log.Fatalf("error listing containers: %v", err)
-	}
+	s.checkConnectivity()
 
 	s.wg.Done()
 
 	for {
 		select {
-		case event := <-events:
+		case event := <-s.events:
 			log.Tracef("received event: %+v", event)
 			switch event.Name {
 			case "start":
@@ -129,7 +156,7 @@ func (s *ContainerStore) init(ctx context.Context) {
 				stat.ID = ""
 				container.Stats.Push(stat)
 			}
-		case <-ctx.Done():
+		case <-s.ctx.Done():
 			return
 		}
 	}

internal/docker/container_store_test.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"testing"
 
+	"github.com/amir20/dozzle/internal/utils"
 	"github.com/magiconair/properties/assert"
 	"github.com/stretchr/testify/mock"
 )
@@ -23,9 +24,9 @@ func (m *mockedClient) FindContainer(id string) (Container, error) {
 	return args.Get(0).(Container), args.Error(1)
 }
 
-func (m *mockedClient) Events(ctx context.Context, events chan<- ContainerEvent) <-chan error {
+func (m *mockedClient) Events(ctx context.Context, events chan<- ContainerEvent) error {
 	args := m.Called(ctx, events)
-	return args.Get(0).(chan error)
+	return args.Error(0)
 }
 
 func (m *mockedClient) ContainerStats(ctx context.Context, id string, stats chan<- ContainerStat) error {
@@ -33,6 +34,11 @@ func (m *mockedClient) ContainerStats(ctx context.Context, id string, stats chan
 	return args.Error(0)
 }
 
+func (m *mockedClient) Host() *Host {
+	args := m.Called()
+	return args.Get(0).(*Host)
+}
+
 func TestContainerStore_List(t *testing.T) {
 
 	client := new(mockedClient)
@@ -42,12 +48,18 @@ func TestContainerStore_List(t *testing.T) {
 			Name: "test",
 		},
 	}, nil)
-	client.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).Return(make(chan error))
+	client.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).Return(nil).Run(func(args mock.Arguments) {
+		ctx := args.Get(0).(context.Context)
+		<-ctx.Done()
+	})
+	client.On("Host").Return(&Host{
+		ID: "localhost",
+	})
 	ctx, cancel := context.WithCancel(context.Background())
 	t.Cleanup(cancel)
 
 	store := NewContainerStore(ctx, client)
-	containers := store.List()
+	containers, _ := store.List()
 
 	assert.Equal(t, containers[0].ID, "1234")
 }
@@ -59,21 +71,23 @@ func TestContainerStore_die(t *testing.T) {
 			ID:    "1234",
 			Name:  "test",
 			State: "running",
+			Stats: utils.NewRingBuffer[ContainerStat](300),
 		},
 	}, nil)
 
-	client.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).Return(make(chan error)).
+	client.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).Return(nil).
 		Run(func(args mock.Arguments) {
 			ctx := args.Get(0).(context.Context)
 			events := args.Get(1).(chan<- ContainerEvent)
-			go func() {
 			events <- ContainerEvent{
 				Name:    "die",
 				ActorID: "1234",
 				Host:    "localhost",
 			}
 			<-ctx.Done()
-			}()
+		})
+	client.On("Host").Return(&Host{
+		ID: "localhost",
 	})
 
 	client.On("ContainerStats", mock.Anything, "1234", mock.AnythingOfType("chan<- docker.ContainerStat")).Return(nil)
@@ -87,6 +101,6 @@ func TestContainerStore_die(t *testing.T) {
 	store.Subscribe(ctx, events)
 	<-events
 
-	containers := store.List()
+	containers, _ := store.List()
 	assert.Equal(t, containers[0].State, "exited")
 }

internal/docker/event_generator_test.go

@@ -152,6 +152,5 @@ func Benchmark_readEvent(b *testing.B) {
 
 	for i := 0; i < b.N; i++ {
 		readEvent(reader, true)
-		// println(message, stream)
 	}
 }

internal/docker/host.go

@@ -19,6 +19,10 @@ type Host struct {
 	ValidCerts bool     `json:"-"`
 }
 
+func (h *Host) String() string {
+	return h.ID
+}
+
 func ParseConnection(connection string) (Host, error) {
 	parts := strings.Split(connection, "|")
 	if len(parts) > 2 {

internal/docker/stats_collector.go

@@ -44,7 +44,7 @@ func (c *StatsCollector) forceStop() {
 	if c.stopper != nil {
 		c.stopper()
 		c.stopper = nil
-		log.Debug("stopping container stats collector due to inactivity")
+		log.Debug("stopping container stats collector")
 	}
 }
 
@@ -52,7 +52,7 @@ func (c *StatsCollector) Stop() {
 	c.mu.Lock()
 	defer c.mu.Unlock()
 	if c.totalStarted.Add(-1) == 0 {
-		log.Debug("scheduled to stop container stats collector")
+		log.Debugf("scheduled to stop container stats collector %s", c.client.Host())
 		c.timer = time.AfterFunc(timeToStop, func() {
 			c.forceStop()
 		})
@@ -62,7 +62,7 @@ func (c *StatsCollector) Stop() {
 func (c *StatsCollector) reset() {
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	log.Debug("resetting timer for container stats collector")
+	log.Debugf("resetting timer for container stats collector %s", c.client.Host())
 	if c.timer != nil {
 		c.timer.Stop()
 	}
@@ -87,7 +87,6 @@ func (sc *StatsCollector) Start(parentCtx context.Context) bool {
 	sc.totalStarted.Add(1)
 
 	var ctx context.Context
-
 	sc.mu.Lock()
 	if sc.stopper != nil {
 		sc.mu.Unlock()
@@ -106,9 +105,18 @@ func (sc *StatsCollector) Start(parentCtx context.Context) bool {
 		log.Errorf("error while listing containers: %v", err)
 	}
 
-	go func() {
 	events := make(chan ContainerEvent)
-		sc.client.Events(ctx, events)
+
+	go func() {
+		log.Debugf("subscribing to docker events from stats collector %s", sc.client.Host())
+		err := sc.client.Events(context.Background(), events)
+		if !errors.Is(err, context.Canceled) {
+			log.Errorf("stats collector unexpectedly disconnected from docker events from %s with %v", sc.client.Host(), err)
+		}
+		sc.forceStop()
+	}()
+
+	go func() {
 		for event := range events {
 			switch event.Name {
 			case "start":

internal/docker/stats_collector_test.go

@@ -17,7 +17,12 @@ func startedCollector(ctx context.Context) *StatsCollector {
 			State: "running",
 		},
 	}, nil)
-	client.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).Return(make(chan error))
+	client.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).
+		Return(nil).
+		Run(func(args mock.Arguments) {
+			ctx := args.Get(0).(context.Context)
+			<-ctx.Done()
+		})
 	client.On("ContainerStats", mock.Anything, mock.Anything, mock.AnythingOfType("chan<- docker.ContainerStat")).
 		Return(nil).
 		Run(func(args mock.Arguments) {
@@ -26,6 +31,9 @@ func startedCollector(ctx context.Context) *StatsCollector {
 				ID: "1234",
 			}
 		})
+	client.On("Host").Return(&Host{
+		ID: "localhost",
+	})
 
 	collector := NewStatsCollector(client)
 	stats := make(chan ContainerStat)

internal/web/events.go

@@ -44,7 +44,15 @@ func (h *handler) streamEvents(w http.ResponseWriter, r *http.Request) {
 	stats := make(chan docker.ContainerStat)
 
 	for _, store := range h.stores {
-		allContainers = append(allContainers, store.List()...)
+		if containers, err := store.List(); err == nil {
+			allContainers = append(allContainers, containers...)
+		} else {
+			log.Errorf("error listing containers: %v", err)
+
+			if _, err := fmt.Fprintf(w, "event: host-unavailable\ndata: %s\n\n", store.Client().Host().ID); err != nil {
+				log.Errorf("error writing event to event stream: %v", err)
+			}
+		}
 		store.SubscribeStats(ctx, stats)
 		store.Subscribe(ctx, events)
 	}
@@ -86,12 +94,13 @@ func (h *handler) streamEvents(w http.ResponseWriter, r *http.Request) {
 			case "start", "die":
 				if event.Name == "start" {
 					log.Debugf("found new container with id: %v", event.ActorID)
-					containers := h.stores[event.Host].List()
+					if containers, err := h.stores[event.Host].List(); err == nil {
 						if err := sendContainersJSON(containers, w); err != nil {
 							log.Errorf("error encoding containers to stream: %v", err)
 							return
 						}
 					}
+				}
 
 				bytes, _ := json.Marshal(event)
 				if _, err := fmt.Fprintf(w, "event: container-%s\ndata: %s\n\n", event.Name, string(bytes)); err != nil {

internal/web/events_test.go

@@ -21,12 +21,11 @@ func Test_handler_streamEvents_happy(t *testing.T) {
 	require.NoError(t, err, "NewRequest should not return an error.")
 
 	mockedClient := new(MockedClient)
-	errChannel := make(chan error)
 
 	mockedClient.On("ListContainers").Return([]docker.Container{}, nil)
-	mockedClient.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).Return(errChannel).Run(func(args mock.Arguments) {
+	mockedClient.On("Events", mock.Anything, mock.AnythingOfType("chan<- docker.ContainerEvent")).Return(nil).Run(func(args mock.Arguments) {
 		messages := args.Get(1).(chan<- docker.ContainerEvent)
-		go func() {
+
 		time.Sleep(50 * time.Millisecond)
 		messages <- docker.ContainerEvent{
 			Name:    "start",
@@ -40,7 +39,6 @@ func Test_handler_streamEvents_happy(t *testing.T) {
 		}
 		time.Sleep(50 * time.Millisecond)
 		cancel()
-		}()
 	})
 	mockedClient.On("FindContainer", "1234").Return(docker.Container{
 		ID:    "1234",
@@ -49,6 +47,10 @@ func Test_handler_streamEvents_happy(t *testing.T) {
 		Stats: utils.NewRingBuffer[docker.ContainerStat](300), // 300 seconds of stats
 	}, nil)
 
+	mockedClient.On("Host").Return(&docker.Host{
+		ID: "localhost",
+	})
+
 	clients := map[string]docker.Client{
 		"localhost": mockedClient,
 	}

internal/web/routes_test.go

@@ -40,9 +40,9 @@ func (m *MockedClient) ContainerLogs(ctx context.Context, id string, since strin
 	return args.Get(0).(io.ReadCloser), args.Error(1)
 }
 
-func (m *MockedClient) Events(ctx context.Context, events chan<- docker.ContainerEvent) <-chan error {
+func (m *MockedClient) Events(ctx context.Context, events chan<- docker.ContainerEvent) error {
 	args := m.Called(ctx, events)
-	return args.Get(0).(chan error)
+	return args.Error(0)
 }
 
 func (m *MockedClient) ContainerStats(context.Context, string, chan<- docker.ContainerStat) error {