resolve service reference into container based on observed state

Signed-off-by: Nicolas De Loof <[email protected]>

pkg/compose/convergence.go

@@ -102,71 +102,13 @@ func (c *convergence) apply(ctx context.Context, project *types.Project, options
 			if utils.StringContains(options.Services, name) {
 				strategy = options.Recreate
 			}
-			err = c.ensureService(ctx, project, service, strategy, options.Inherit, options.Timeout)
-			if err != nil {
-				return err
-			}
-
-			c.updateProject(project, name)
-			return nil
+			return c.ensureService(ctx, project, service, strategy, options.Inherit, options.Timeout)
 		})(ctx)
 	})
 }
 
 var mu sync.Mutex
 
-// updateProject updates project after service converged, so dependent services relying on `service:xx` can refer to actual containers.
-func (c *convergence) updateProject(project *types.Project, serviceName string) {
-	// operation is protected by a Mutex so that we can safely update project.Services while running concurrent convergence on services
-	mu.Lock()
-	defer mu.Unlock()
-
-	cnts := c.getObservedState(serviceName)
-	for i, s := range project.Services {
-		updateServices(&s, cnts)
-		project.Services[i] = s
-	}
-}
-
-func updateServices(service *types.ServiceConfig, cnts Containers) {
-	if len(cnts) == 0 {
-		return
-	}
-
-	for _, str := range []*string{&service.NetworkMode, &service.Ipc, &service.Pid} {
-		if d := getDependentServiceFromMode(*str); d != "" {
-			if serviceContainers := cnts.filter(isService(d)); len(serviceContainers) > 0 {
-				*str = types.NetworkModeContainerPrefix + serviceContainers[0].ID
-			}
-		}
-	}
-	var links []string
-	for _, serviceLink := range service.Links {
-		parts := strings.Split(serviceLink, ":")
-		serviceName := serviceLink
-		serviceAlias := ""
-		if len(parts) == 2 {
-			serviceName = parts[0]
-			serviceAlias = parts[1]
-		}
-		if serviceName != service.Name {
-			links = append(links, serviceLink)
-			continue
-		}
-		for _, container := range cnts {
-			name := getCanonicalContainerName(container)
-			if serviceAlias != "" {
-				links = append(links,
-					fmt.Sprintf("%s:%s", name, serviceAlias))
-			}
-			links = append(links,
-				fmt.Sprintf("%s:%s", name, name),
-				fmt.Sprintf("%s:%s", name, getContainerNameWithoutProject(container)))
-		}
-		service.Links = links
-	}
-}
-
 func (c *convergence) ensureService(ctx context.Context, project *types.Project, service types.ServiceConfig, recreate string, inherit bool, timeout *time.Duration) error {
 	expected, err := getScale(service)
 	if err != nil {
@@ -178,7 +120,7 @@ func (c *convergence) ensureService(ctx context.Context, project *types.Project,
 
 	eg, _ := errgroup.WithContext(ctx)
 
-	err = c.resolveVolumeFrom(&service)
+	err = c.resolveServiceReferences(&service)
 	if err != nil {
 		return err
 	}
@@ -263,6 +205,25 @@ func (c *convergence) ensureService(ctx context.Context, project *types.Project,
 	return err
 }
 
+// resolveServiceReferences replaces reference to another service with reference to an actual container
+func (c *convergence) resolveServiceReferences(service *types.ServiceConfig) error {
+	err := c.resolveVolumeFrom(service)
+	if err != nil {
+		return err
+	}
+
+	err = c.resolveLinks(service)
+	if err != nil {
+		return err
+	}
+
+	err = c.resolveSharedNamespaces(service)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func (c *convergence) resolveVolumeFrom(service *types.ServiceConfig) error {
 	for i, vol := range service.VolumesFrom {
 		spec := strings.Split(vol, ":")
@@ -283,6 +244,66 @@ func (c *convergence) resolveVolumeFrom(service *types.ServiceConfig) error {
 	return nil
 }
 
+func (c *convergence) resolveLinks(service *types.ServiceConfig) error {
+	var links []string
+	for _, serviceLink := range service.Links {
+		parts := strings.Split(serviceLink, ":")
+		serviceName := serviceLink
+		serviceAlias := ""
+		if len(parts) == 2 {
+			serviceName = parts[0]
+			serviceAlias = parts[1]
+		}
+		dependencies := c.getObservedState(serviceName)
+		if len(dependencies) == 0 {
+			return fmt.Errorf("cannot link to service %s: container missing", serviceName)
+		}
+		for _, container := range dependencies {
+			name := getCanonicalContainerName(container)
+			if serviceAlias != "" {
+				links = append(links,
+					fmt.Sprintf("%s:%s", name, serviceAlias))
+			}
+			links = append(links,
+				fmt.Sprintf("%s:%s", name, name),
+				fmt.Sprintf("%s:%s", name, getContainerNameWithoutProject(container)))
+		}
+	}
+	service.Links = links
+	return nil
+}
+
+func (c *convergence) resolveSharedNamespaces(service *types.ServiceConfig) error {
+	str := service.NetworkMode
+	if name := getDependentServiceFromMode(str); name != "" {
+		dependencies := c.getObservedState(name)
+		if len(dependencies) == 0 {
+			return fmt.Errorf("cannot share network namespace with service %s: container missing", name)
+		}
+		service.NetworkMode = types.ContainerPrefix + dependencies.sorted()[0].ID
+	}
+
+	str = service.Ipc
+	if name := getDependentServiceFromMode(str); name != "" {
+		dependencies := c.getObservedState(name)
+		if len(dependencies) == 0 {
+			return fmt.Errorf("cannot share IPC namespace with service %s: container missing", name)
+		}
+		service.Ipc = types.ContainerPrefix + dependencies.sorted()[0].ID
+	}
+
+	str = service.Pid
+	if name := getDependentServiceFromMode(str); name != "" {
+		dependencies := c.getObservedState(name)
+		if len(dependencies) == 0 {
+			return fmt.Errorf("cannot share PID namespace with service %s: container missing", name)
+		}
+		service.Pid = types.ContainerPrefix + dependencies.sorted()[0].ID
+	}
+
+	return nil
+}
+
 func mustRecreate(expected types.ServiceConfig, actual moby.Container, policy string) (bool, error) {
 	if policy == api.RecreateNever {
 		return false, nil

pkg/compose/run.go

@@ -90,7 +90,6 @@ func (s *composeService) prepareRun(ctx context.Context, project *types.Project,
 	if err != nil {
 		return "", err
 	}
-	updateServices(&service, observedState)
 
 	if !opts.NoDeps {
 		if err := s.waitDependencies(ctx, project, service.DependsOn, observedState); err != nil {
@@ -104,6 +103,11 @@ func (s *composeService) prepareRun(ctx context.Context, project *types.Project,
 		Labels:            mergeLabels(service.Labels, service.CustomLabels),
 	}
 
+	err = newConvergence(project.ServiceNames(), observedState, s).resolveServiceReferences(&service)
+	if err != nil {
+		return "", err
+	}
+
 	created, err := s.createContainer(ctx, project, service, service.ContainerName, 1, createOpts)
 	if err != nil {
 		return "", err

pkg/e2e/fixtures/no-deps/links.yaml

@@ -0,0 +1,8 @@
+services:
+  app:
+    image: nginx:alpine
+    links:
+      - db
+
+  db:
+    image: nginx:alpine

pkg/e2e/fixtures/no-deps/network-mode.yaml

@@ -0,0 +1,7 @@
+services:
+  app:
+    image: nginx:alpine
+    network_mode: service:db
+
+  db:
+    image: nginx:alpine

pkg/e2e/noDeps_test.go

@@ -42,3 +42,37 @@ func TestNoDepsVolumeFrom(t *testing.T) {
 	res := c.RunDockerComposeCmdNoCheck(t, "-f", "fixtures/no-deps/volume-from.yaml", "--project-name", projectName, "up", "--no-deps", "-d", "app")
 	res.Assert(t, icmd.Expected{ExitCode: 1, Err: "cannot share volume with service db: container missing"})
 }
+
+func TestNoDepsLinks(t *testing.T) {
+	c := NewParallelCLI(t)
+	const projectName = "e2e-no-deps-links"
+	t.Cleanup(func() {
+		c.RunDockerComposeCmd(t, "--project-name", projectName, "down")
+	})
+
+	c.RunDockerComposeCmd(t, "-f", "fixtures/no-deps/links.yaml", "--project-name", projectName, "up", "-d")
+
+	c.RunDockerComposeCmd(t, "-f", "fixtures/no-deps/links.yaml", "--project-name", projectName, "up", "--no-deps", "-d", "app")
+
+	c.RunDockerCmd(t, "rm", "-f", fmt.Sprintf("%s-db-1", projectName))
+
+	res := c.RunDockerComposeCmdNoCheck(t, "-f", "fixtures/no-deps/links.yaml", "--project-name", projectName, "up", "--no-deps", "-d", "app")
+	res.Assert(t, icmd.Expected{ExitCode: 1, Err: "cannot link to service db: container missing"})
+}
+
+func TestNoDepsNetworkMode(t *testing.T) {
+	c := NewParallelCLI(t)
+	const projectName = "e2e-no-deps-network-mode"
+	t.Cleanup(func() {
+		c.RunDockerComposeCmd(t, "--project-name", projectName, "down")
+	})
+
+	c.RunDockerComposeCmd(t, "-f", "fixtures/no-deps/network-mode.yaml", "--project-name", projectName, "up", "-d")
+
+	c.RunDockerComposeCmd(t, "-f", "fixtures/no-deps/network-mode.yaml", "--project-name", projectName, "up", "--no-deps", "-d", "app")
+
+	c.RunDockerCmd(t, "rm", "-f", fmt.Sprintf("%s-db-1", projectName))
+
+	res := c.RunDockerComposeCmdNoCheck(t, "-f", "fixtures/no-deps/network-mode.yaml", "--project-name", projectName, "up", "--no-deps", "-d", "app")
+	res.Assert(t, icmd.Expected{ExitCode: 1, Err: "cannot share network namespace with service db: container missing"})
+}