Merge pull request #416 from arnested/harden-entrygroups

harden entrygroups

Author: arnested

container.go

@@ -24,7 +24,7 @@ func handleContainer(
 	docker *client.Client,
 	containerID string,
 	egs *entryGroups,
-	status string,
+	status events.Action,
 	config Config,
 ) error {
 	entryGroup, commit, err := egs.get(containerID)
@@ -140,7 +140,7 @@ func listen(ctx context.Context, config Config, docker *client.Client, egs *entr
 		case err := <-errs:
 			panic(fmt.Errorf("go error reading docker events: %w", err))
 		case msg := <-msgs:
-			err := handleContainer(ctx, docker, msg.ID, egs, msg.Status, config)
+			err := handleContainer(ctx, docker, msg.Actor.ID, egs, msg.Action, config)
 			if err != nil {
 				log.Logf(log.PriErr, "handling container: %v", err)
 			}

entry_groups.go

@@ -24,6 +24,8 @@ func newEntryGroups(avahiServer *avahi.Server) *entryGroups {
 
 func (e *entryGroups) get(containerID string) (*avahi.EntryGroup, func(), error) {
 	commit := func() {
+		defer e.mutex.Unlock()
+
 		empty, err := e.groups[containerID].IsEmpty()
 		if err != nil {
 			log.Logf(log.PriErr, "checking whether Avahi entry group is empty: %v", err)
@@ -35,18 +37,18 @@ func (e *entryGroups) get(containerID string) (*avahi.EntryGroup, func(), error)
 				log.Logf(log.PriErr, "error committing: %v", err)
 			}
 		}
-
-		e.mutex.Unlock()
 	}
 
 	e.mutex.Lock()
 	if _, ok := e.groups[containerID]; !ok {
-		eg, err := e.avahiServer.EntryGroupNew()
+		entryGroup, err := e.avahiServer.EntryGroupNew()
 		if err != nil {
-			return nil, commit, fmt.Errorf("error creating new entry group: %w", err)
+			e.mutex.Unlock()
+
+			return nil, func() {}, fmt.Errorf("error creating new entry group: %w", err)
 		}
 
-		e.groups[containerID] = eg
+		e.groups[containerID] = entryGroup
 	}
 
 	return e.groups[containerID], commit, nil

internal/container/container.go

@@ -56,7 +56,7 @@ func (c Container) Services() map[string]uint16 {
 			continue
 		}
 
-		//nolint:mnd,gomnd
+		//nolint:mnd
 		if portNumber > 65535 {
 			log.Logf(log.PriErr, "Port number %d is too large", portNumber)
 

internal/container/container_test.go

@@ -7,11 +7,11 @@ import (
 	"os"
 	"testing"
 
-	"github.com/docker/docker/api/types"
+	docker_container "github.com/docker/docker/api/types/container"
 	"ldddns.arnested.dk/internal/container"
 )
 
-func containerJSON() (*types.ContainerJSON, error) {
+func containerJSON() (*docker_container.InspectResponse, error) {
 	jsonFile, err := os.Open("../../testdata/container.json")
 	if err != nil {
 		return nil, fmt.Errorf("opening JSON test data: %w", err)
@@ -25,7 +25,7 @@ func containerJSON() (*types.ContainerJSON, error) {
 	}
 
 	// we initialize our Users array
-	var containerJSON *types.ContainerJSON
+	var containerJSON *docker_container.InspectResponse
 
 	err = json.Unmarshal(byteValue, &containerJSON)
 	if err != nil {

internal/hostname/hostname_test.go

@@ -7,12 +7,12 @@ import (
 	"os"
 	"testing"
 
-	"github.com/docker/docker/api/types"
+	docker_container "github.com/docker/docker/api/types/container"
 	"ldddns.arnested.dk/internal/container"
 	"ldddns.arnested.dk/internal/hostname"
 )
 
-func containerJSON() (*types.ContainerJSON, error) {
+func containerJSON() (*docker_container.InspectResponse, error) {
 	jsonFile, err := os.Open("../../testdata/container.json")
 	if err != nil {
 		return nil, fmt.Errorf("opening JSON test data: %w", err)
@@ -26,7 +26,7 @@ func containerJSON() (*types.ContainerJSON, error) {
 	}
 
 	// we initialize our Users array
-	var containerJSON *types.ContainerJSON
+	var containerJSON *docker_container.InspectResponse
 
 	err = json.Unmarshal(byteValue, &containerJSON)
 	if err != nil {