Add logger to container and factory

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

cgroups.go

@@ -7,6 +7,7 @@ import (
 )
 
 type CgroupManager interface {
+	String() string
 	GetPids(*cgroups.Cgroup) ([]int, error)
 	GetStats(*cgroups.Cgroup) (*cgroups.Stats, error)
 }
@@ -29,6 +30,10 @@ func (m *systemdCgroupManager) GetStats(config *cgroups.Cgroup) (*cgroups.Stats,
 	return systemd.GetStats(config)
 }
 
+func (m *systemdCgroupManager) String() string {
+	return "systemd"
+}
+
 type fsCgroupsManager struct {
 }
 
@@ -39,3 +44,7 @@ func (m *fsCgroupsManager) GetPids(config *cgroups.Cgroup) ([]int, error) {
 func (m *fsCgroupsManager) GetStats(config *cgroups.Cgroup) (*cgroups.Stats, error) {
 	return fs.GetStats(config)
 }
+
+func (m *fsCgroupsManager) String() string {
+	return "fs"
+}

linux_container.go

@@ -2,14 +2,18 @@
 
 package libcontainer
 
-import "github.com/docker/libcontainer/network"
+import (
+	"github.com/Sirupsen/logrus"
+	"github.com/docker/libcontainer/network"
+)
 
 type linuxContainer struct {
 	id            string
 	root          string
 	config        *Config
 	state         *State
 	cgroupManager CgroupManager
+	logger        *logrus.Logger
 }
 
 func (c *linuxContainer) ID() string {
@@ -25,6 +29,7 @@ func (c *linuxContainer) RunState() (RunState, error) {
 }
 
 func (c *linuxContainer) Processes() ([]int, error) {
+	c.logger.Debug("fetch container processes")
 	pids, err := c.cgroupManager.GetPids(c.config.Cgroups)
 	if err != nil {
 		return nil, newGenericError(err, SystemError)
@@ -33,6 +38,7 @@ func (c *linuxContainer) Processes() ([]int, error) {
 }
 
 func (c *linuxContainer) Stats() (*ContainerStats, error) {
+	c.logger.Debug("fetch container stats")
 	var (
 		err   error
 		stats = &ContainerStats{}
@@ -48,29 +54,36 @@ func (c *linuxContainer) Stats() (*ContainerStats, error) {
 }
 
 func (c *linuxContainer) StartProcess(config *ProcessConfig) (int, error) {
+	c.logger.Debug("start new container process")
 	panic("not implemented")
 }
 
 func (c *linuxContainer) Destroy() error {
+	c.logger.Debug("destroy container")
 	panic("not implemented")
 }
 
 func (c *linuxContainer) Pause() error {
+	c.logger.Debug("pause container")
 	panic("not implemented")
 }
 
 func (c *linuxContainer) Resume() error {
+	c.logger.Debug("resume container")
 	panic("not implemented")
 }
 
 func (c *linuxContainer) Signal(pid, signal int) error {
+	c.logger.Debugf("sending signal %d to pid %d", signal, pid)
 	panic("not implemented")
 }
 
 func (c *linuxContainer) Wait() (int, error) {
+	c.logger.Debug("wait container")
 	panic("not implemented")
 }
 
 func (c *linuxContainer) WaitProcess(pid int) (int, error) {
+	c.logger.Debugf("wait process %d", pid)
 	panic("not implemented")
 }

linux_factory.go

@@ -6,6 +6,8 @@ import (
 	"encoding/json"
 	"os"
 	"path/filepath"
+
+	"github.com/Sirupsen/logrus"
 )
 
 const (
@@ -14,20 +16,24 @@ const (
 )
 
 // New returns a linux based container factory based in the root directory.
-func New(root string) (Factory, error) {
+func New(root string, logger *logrus.Logger) (Factory, error) {
 	if err := os.MkdirAll(root, 0700); err != nil {
 		return nil, newGenericError(err, SystemError)
 	}
 
 	return &linuxFactory{
-		root: root,
+		root:   root,
+		logger: logger,
 	}, nil
 }
 
 // linuxFactory implements the default factory interface for linux based systems.
 type linuxFactory struct {
 	// root is the root directory
 	root string
+
+	// standard logger for all packages
+	logger *logrus.Logger
 }
 
 func (l *linuxFactory) Create(id string, config *Config) (Container, error) {
@@ -36,22 +42,27 @@ func (l *linuxFactory) Create(id string, config *Config) (Container, error) {
 
 func (l *linuxFactory) Load(id string) (Container, error) {
 	containerRoot := filepath.Join(l.root, id)
+	l.logger.Debugf("loading container config from %s", containerRoot)
 	config, err := l.loadContainerConfig(containerRoot)
 	if err != nil {
 		return nil, err
 	}
 
+	l.logger.Debugf("loading container state from %s", containerRoot)
 	state, err := l.loadContainerState(containerRoot)
 	if err != nil {
 		return nil, err
 	}
 
+	cgroupManager := newCgroupsManager()
+	l.logger.Debugf("using %s as cgroup manager", cgroupManager)
 	return &linuxContainer{
 		id:            id,
 		root:          containerRoot,
 		config:        config,
 		state:         state,
-		cgroupManager: newCgroupsManager(),
+		cgroupManager: cgroupManager,
+		logger:        l.logger,
 	}, nil
 }
 

nsinit/main.go

@@ -5,11 +5,13 @@ import (
 	"os"
 	"strings"
 
+	"github.com/Sirupsen/logrus"
 	"github.com/codegangsta/cli"
 )
 
 var (
 	logPath = os.Getenv("log")
+	logger  = logrus.New()
 	argvs   = make(map[string]*rFunc)
 )
 

nsinit/stats.go

@@ -16,7 +16,7 @@ var statsCommand = cli.Command{
 }
 
 func statsAction(context *cli.Context) {
-	factory, err := libcontainer.New(context.GlobalString("root"))
+	factory, err := libcontainer.New(context.GlobalString("root"), logger)
 	if err != nil {
 		log.Fatal(err)
 	}