environment(docker): cleanup code

environment/docker/container.go

@@ -309,16 +309,21 @@ func (e *Environment) followOutput() error {
 	if err != nil {
 		return err
 	}
+
 	go func(reader io.ReadCloser) {
 		defer reader.Close()
-		evts := e.Events()
+
+		events := e.Events()
+
 		err := system.ScanReader(reader, func(line string) {
-			evts.Publish(environment.ConsoleOutputEvent, line)
+			events.Publish(environment.ConsoleOutputEvent, line)
 		})
+
 		if err != nil && err != io.EOF {
 			log.WithField("error", err).WithField("container_id", e.Id).Warn("error processing scanner line in console output")
 		}
 	}(reader)
+
 	return nil
 }
 
@@ -405,9 +410,11 @@ func (e *Environment) ensureImageExists(image string) error {
 	// I'm not sure what the best approach here is, but this will block execution until the image
 	// is done being pulled, which is what we need.
 	scanner := bufio.NewScanner(out)
+
 	for scanner.Scan() {
 		s := imagePullStatus{}
 		fmt.Println(scanner.Text())
+
 		if err := json.Unmarshal(scanner.Bytes(), &s); err == nil {
 			e.Events().Publish(environment.DockerImagePullStatus, s.Status+" "+s.Progress)
 		}

environment/docker/environment.go

@@ -82,8 +82,9 @@ func (e *Environment) Type() string {
 // Set if this process is currently attached to the process.
 func (e *Environment) SetStream(s *types.HijackedResponse) {
 	e.mu.Lock()
+	defer e.mu.Unlock()
+
 	e.stream = s
-	e.mu.Unlock()
 }
 
 // Determine if the this process is currently attached to the container.
@@ -98,6 +99,7 @@ func (e *Environment) Events() *events.EventBus {
 	e.eventMu.Do(func() {
 		e.emitter = events.New()
 	})
+
 	return e.emitter
 }
 
@@ -174,12 +176,14 @@ func (e *Environment) Config() *environment.Configuration {
 // Sets the stop configuration for the environment.
 func (e *Environment) SetStopConfiguration(c api.ProcessStopConfiguration) {
 	e.mu.Lock()
+	defer e.mu.Unlock()
+
 	e.meta.Stop = c
-	e.mu.Unlock()
 }
 
 func (e *Environment) SetImage(i string) {
 	e.mu.Lock()
+	defer e.mu.Unlock()
+
 	e.meta.Image = i
-	e.mu.Unlock()
 }

environment/docker/power.go

@@ -20,10 +20,9 @@ import (
 //
 // This process will also confirm that the server environment exists and is in a bootable
 // state. This ensures that unexpected container deletion while Wings is running does
-// not result in the server becoming unbootable.
+// not result in the server becoming un-bootable.
 func (e *Environment) OnBeforeStart() error {
-	// Always destroy and re-create the server container to ensure that synced data from
+	// Always destroy and re-create the server container to ensure that synced data from the Panel is used.
-	// the Panel is usee.
 	if err := e.client.ContainerRemove(context.Background(), e.Id, types.ContainerRemoveOptions{RemoveVolumes: true}); err != nil {
 		if !client.IsErrNotFound(err) {
 			return errors.WithMessage(err, "failed to remove server docker container during pre-boot")
@@ -49,6 +48,7 @@ func (e *Environment) OnBeforeStart() error {
 // call to OnBeforeStart().
 func (e *Environment) Start() error {
 	sawError := false
+
 	// If sawError is set to true there was an error somewhere in the pipeline that
 	// got passed up, but we also want to ensure we set the server to be offline at
 	// that point.
@@ -235,7 +235,7 @@ func (e *Environment) Terminate(signal os.Signal) error {
 
 	sig := strings.TrimSuffix(strings.TrimPrefix(signal.String(), "signal "), "ed")
 
-	if err := e.client.ContainerKill(context.Background(), e.Id, sig); err != nil {
+	if err := e.client.ContainerKill(context.Background(), e.Id, sig); err != nil && !client.IsErrNotFound(err) {
 		return err
 	}
 

environment/docker/stream.go

@@ -19,8 +19,9 @@ var ErrNotAttached = errors.New("not attached to instance")
 
 func (e *Environment) setStream(s *types.HijackedResponse) {
 	e.mu.Lock()
+	defer e.mu.Unlock()
+
 	e.stream = s
-	e.mu.Unlock()
 }
 
 // Sends the specified command to the stdin of the running container instance. There is no
@@ -71,7 +72,7 @@ func (e *Environment) Readlog(lines int) ([]string, error) {
 // Docker stores the logs for server output in a JSON format. This function will iterate over the JSON
 // that was read from the log file and parse it into a more human readable format.
 func (e *Environment) parseLogToStrings(b []byte) ([]string, error) {
-	var hasError = false
+	hasError := false
 	var out []string
 
 	scanner := bufio.NewScanner(bytes.NewReader(b))