Include pre-start hook images in pull and config

cmd/compose/config.go

@@ -513,7 +513,9 @@ func runConfigImages(ctx context.Context, dockerCli command.Cli, opts configOpti
 	}
 
 	for _, s := range project.Services {
-		_, _ = fmt.Fprintln(dockerCli.Out(), api.GetImageNameOrDefault(s, project.Name))
+		for _, imageName := range api.GetImageNamesForService(s, project.Name) {
+			_, _ = fmt.Fprintln(dockerCli.Out(), imageName)
+		}
 	}
 	return nil
 }

cmd/compose/pull.go

@@ -88,7 +88,7 @@ func (opts pullOptions) apply(project *types.Project, services []string) (*types
 
 	if opts.policy != "" {
 		for i, service := range project.Services {
-			if service.Image == "" {
+			if service.Image == "" && !hasPreStartHookImage(service) {
 				continue
 			}
 			service.PullPolicy = opts.policy
@@ -98,6 +98,15 @@ func (opts pullOptions) apply(project *types.Project, services []string) (*types
 	return project, nil
 }
 
+func hasPreStartHookImage(service types.ServiceConfig) bool {
+	for _, hook := range service.PreStart {
+		if hook.Image != "" {
+			return true
+		}
+	}
+	return false
+}
+
 func runPull(ctx context.Context, dockerCli command.Cli, backendOptions *BackendOptions, opts pullOptions, services []string) error {
 	backend, err := compose.NewComposeService(dockerCli, backendOptions.Options...)
 	if err != nil {

cmd/compose/pullOptions_test.go

@@ -44,6 +44,13 @@ func TestApplyPullOptions(t *testing.T) {
 				Name:  "must-pull",
 				Image: "registry.example.com/another-service",
 			},
+			"hook-only": {
+				Name: "hook-only",
+				Build: &types.BuildConfig{
+					Context: ".",
+				},
+				PreStart: []types.ServiceHook{{Image: "registry.example.com/hook"}},
+			},
 		},
 	}
 	project, err := pullOptions{
@@ -54,4 +61,5 @@ func TestApplyPullOptions(t *testing.T) {
 	assert.Equal(t, project.Services["must-build"].PullPolicy, "") // still default
 	assert.Equal(t, project.Services["has-build"].PullPolicy, types.PullPolicyMissing)
 	assert.Equal(t, project.Services["must-pull"].PullPolicy, types.PullPolicyMissing)
+	assert.Equal(t, project.Services["hook-only"].PullPolicy, types.PullPolicyMissing)
 }

pkg/api/api.go

@@ -760,3 +760,27 @@ func GetImageNameOrDefault(service types.ServiceConfig, projectName string) stri
 	}
 	return imageName
 }
+
+// GetImageNamesForService returns the image names required by a service.
+//
+// This includes the service image (or its default build image name), plus any
+// distinct image explicitly referenced by pre_start lifecycle hooks. post_start
+// and pre_stop hooks are intentionally excluded because Compose executes those
+// hooks inside the service container instead of creating a container from the
+// hook image field.
+func GetImageNamesForService(service types.ServiceConfig, projectName string) []string {
+	imageNames := []string{GetImageNameOrDefault(service, projectName)}
+	seen := map[string]struct{}{imageNames[0]: {}}
+
+	for _, hook := range service.PreStart {
+		if hook.Image == "" {
+			continue
+		}
+		if _, ok := seen[hook.Image]; ok {
+			continue
+		}
+		imageNames = append(imageNames, hook.Image)
+		seen[hook.Image] = struct{}{}
+	}
+	return imageNames
+}

pkg/api/api_test.go

@@ -36,3 +36,20 @@ func TestRunOptionsEnvironmentMap(t *testing.T) {
 	assert.Equal(t, *env["ZOT"], "")
 	assert.Check(t, env["QIX"] == nil)
 }
+
+func TestGetImageNamesForServiceIncludesPreStartHooks(t *testing.T) {
+	service := types.ServiceConfig{
+		Name:  "demo",
+		Image: "alpine:3.20",
+		PreStart: []types.ServiceHook{
+			{Image: "alpine:3.20"},
+			{Image: "alpine:3.19"},
+			{Image: "alpine:3.19"},
+			{},
+		},
+		PostStart: []types.ServiceHook{{Image: "unused-post-start"}},
+		PreStop:   []types.ServiceHook{{Image: "unused-pre-stop"}},
+	}
+
+	assert.DeepEqual(t, GetImageNamesForService(service, "hooktest"), []string{"alpine:3.20", "alpine:3.19"})
+}

pkg/compose/build.go

@@ -192,7 +192,9 @@ func resolveImageVolumes(service *types.ServiceConfig, images map[string]api.Ima
 func (s *composeService) getLocalImagesDigests(ctx context.Context, project *types.Project) (map[string]api.ImageSummary, error) {
 	imageNames := utils.Set[string]{}
 	for _, s := range project.Services {
-		imageNames.Add(api.GetImageNameOrDefault(s, project.Name))
+		for _, imageName := range api.GetImageNamesForService(s, project.Name) {
+			imageNames.Add(imageName)
+		}
 		for _, volume := range s.Volumes {
 			if volume.Type == types.VolumeTypeImage {
 				imageNames.Add(volume.Source)

pkg/compose/pull.go

@@ -56,35 +56,29 @@ func (s *composeService) pull(ctx context.Context, project *types.Project, opts
 		return err
 	}
 
-	eg, ctx := errgroup.WithContext(ctx)
-	eg.SetLimit(s.maxConcurrency)
-
 	var (
 		mustBuild         []string
-		pullErrors        = make([]error, len(project.Services))
 		imagesBeingPulled = map[string]string{}
+		targets           []types.ServiceConfig
 	)
 
-	i := 0
-	for name, service := range project.Services {
-		if service.Image == "" {
-			s.events.On(api.Resource{
-				ID:      name,
-				Status:  api.Done,
-				Text:    "Skipped",
-				Details: "No image to be pulled",
-			})
-			continue
+	queuePull := func(service types.ServiceConfig) {
+		if _, ok := imagesBeingPulled[service.Image]; ok {
+			return
 		}
+		imagesBeingPulled[service.Image] = service.Name
+		targets = append(targets, service)
+	}
 
+	maybePull := func(service types.ServiceConfig) {
 		switch service.PullPolicy {
 		case types.PullPolicyNever, types.PullPolicyBuild:
 			s.events.On(api.Resource{
 				ID:     "Image " + service.Image,
 				Status: api.Done,
 				Text:   "Skipped",
 			})
-			continue
+			return
 		case types.PullPolicyMissing, types.PullPolicyIfNotPresent:
 			if imageAlreadyPresent(service.Image, images) {
 				s.events.On(api.Resource{
@@ -93,7 +87,7 @@ func (s *composeService) pull(ctx context.Context, project *types.Project, opts
 					Text:    "Skipped",
 					Details: "Image is already present locally",
 				})
-				continue
+				return
 			}
 		}
 
@@ -104,16 +98,44 @@ func (s *composeService) pull(ctx context.Context, project *types.Project, opts
 				Text:    "Skipped",
 				Details: "Image can be built",
 			})
-			continue
+			return
 		}
 
-		if _, ok := imagesBeingPulled[service.Image]; ok {
-			continue
+		queuePull(service)
+	}
+
+	for name, service := range project.Services {
+		if service.Image == "" {
+			s.events.On(api.Resource{
+				ID:      name,
+				Status:  api.Done,
+				Text:    "Skipped",
+				Details: "No image to be pulled",
+			})
+		} else {
+			maybePull(service)
 		}
 
-		imagesBeingPulled[service.Image] = service.Name
+		preStartImages := map[string]struct{}{}
+		for i, hook := range service.PreStart {
+			hookService, ok := preStartHookImageService(service, i, hook)
+			if !ok || hookService.Image == service.Image {
+				continue
+			}
+			if _, ok := preStartImages[hookService.Image]; ok {
+				continue
+			}
+			preStartImages[hookService.Image] = struct{}{}
+			maybePull(hookService)
+		}
+	}
 
+	eg, ctx := errgroup.WithContext(ctx)
+	eg.SetLimit(s.maxConcurrency)
+	pullErrors := make([]error, len(targets))
+	for i, service := range targets {
 		idx := i
+		service := service
 		eg.Go(func() error {
 			_, err := s.pullServiceImage(ctx, service, opts.Quiet, project.Environment["DOCKER_DEFAULT_PLATFORM"])
 			if err != nil {
@@ -132,11 +154,9 @@ func (s *composeService) pull(ctx context.Context, project *types.Project, opts
 			}
 			return nil
 		})
-		i++
 	}
 
 	err = eg.Wait()
-
 	if len(mustBuild) > 0 {
 		logrus.Warnf("WARNING: Some service image(s) must be built from source by running:\n    docker compose build %s", strings.Join(mustBuild, " "))
 	}
@@ -313,6 +333,24 @@ func (s *composeService) pullRequiredImages(ctx context.Context, project *types.
 			}
 		}
 
+		preStartImages := map[string]struct{}{}
+		for i, hook := range service.PreStart {
+			hookService, ok := preStartHookImageService(service, i, hook)
+			if !ok || hookService.Image == service.Image {
+				continue
+			}
+			if _, ok := preStartImages[hookService.Image]; ok || pullTargetForImageExists(needPull, hookService.Image) {
+				continue
+			}
+			preStartImages[hookService.Image] = struct{}{}
+			pull, err := mustPull(hookService, images)
+			if err != nil {
+				return err
+			}
+			if pull {
+				needPull[hookService.Name] = hookService
+			}
+		}
 	}
 	if len(needPull) == 0 {
 		return nil
@@ -348,6 +386,28 @@ func (s *composeService) pullRequiredImages(ctx context.Context, project *types.
 	return err
 }
 
+func preStartHookImageService(service types.ServiceConfig, index int, hook types.ServiceHook) (types.ServiceConfig, bool) {
+	if hook.Image == "" {
+		return types.ServiceConfig{}, false
+	}
+	hookName := fmt.Sprintf("%s:pre_start %d", service.Name, index)
+	return types.ServiceConfig{
+		Name:       hookName,
+		Image:      hook.Image,
+		PullPolicy: service.PullPolicy,
+		Platform:   service.Platform,
+	}, true
+}
+
+func pullTargetForImageExists(targets map[string]types.ServiceConfig, imageName string) bool {
+	for _, target := range targets {
+		if target.Image == imageName {
+			return true
+		}
+	}
+	return false
+}
+
 func mustPull(service types.ServiceConfig, images map[string]api.ImageSummary) (bool, error) {
 	if service.Provider != nil {
 		return false, nil