| package docker |
| |
| import ( |
| "container/list" |
| "fmt" |
| "github.com/dotcloud/docker/auth" |
| "io" |
| "io/ioutil" |
| "log" |
| "os" |
| "os/exec" |
| "path" |
| "sort" |
| "strings" |
| "time" |
| ) |
| |
| type Capabilities struct { |
| MemoryLimit bool |
| SwapLimit bool |
| } |
| |
| type Runtime struct { |
| root string |
| repository string |
| containers *list.List |
| networkManager *NetworkManager |
| graph *Graph |
| repositories *TagStore |
| authConfig *auth.AuthConfig |
| idIndex *TruncIndex |
| capabilities *Capabilities |
| kernelVersion *KernelVersionInfo |
| autoRestart bool |
| volumes *Graph |
| } |
| |
| var sysInitPath string |
| |
| func init() { |
| sysInitPath = SelfPath() |
| } |
| |
| func (runtime *Runtime) List() []*Container { |
| containers := new(History) |
| for e := runtime.containers.Front(); e != nil; e = e.Next() { |
| containers.Add(e.Value.(*Container)) |
| } |
| return *containers |
| } |
| |
| func (runtime *Runtime) getContainerElement(id string) *list.Element { |
| for e := runtime.containers.Front(); e != nil; e = e.Next() { |
| container := e.Value.(*Container) |
| if container.Id == id { |
| return e |
| } |
| } |
| return nil |
| } |
| |
| func (runtime *Runtime) Get(name string) *Container { |
| id, err := runtime.idIndex.Get(name) |
| if err != nil { |
| return nil |
| } |
| e := runtime.getContainerElement(id) |
| if e == nil { |
| return nil |
| } |
| return e.Value.(*Container) |
| } |
| |
| func (runtime *Runtime) Exists(id string) bool { |
| return runtime.Get(id) != nil |
| } |
| |
| func (runtime *Runtime) containerRoot(id string) string { |
| return path.Join(runtime.repository, id) |
| } |
| |
| func (runtime *Runtime) mergeConfig(userConf, imageConf *Config) { |
| if userConf.Hostname == "" { |
| userConf.Hostname = imageConf.Hostname |
| } |
| if userConf.User == "" { |
| userConf.User = imageConf.User |
| } |
| if userConf.Memory == 0 { |
| userConf.Memory = imageConf.Memory |
| } |
| if userConf.MemorySwap == 0 { |
| userConf.MemorySwap = imageConf.MemorySwap |
| } |
| if userConf.PortSpecs == nil || len(userConf.PortSpecs) == 0 { |
| userConf.PortSpecs = imageConf.PortSpecs |
| } |
| if !userConf.Tty { |
| userConf.Tty = userConf.Tty |
| } |
| if !userConf.OpenStdin { |
| userConf.OpenStdin = imageConf.OpenStdin |
| } |
| if !userConf.StdinOnce { |
| userConf.StdinOnce = imageConf.StdinOnce |
| } |
| if userConf.Env == nil || len(userConf.Env) == 0 { |
| userConf.Env = imageConf.Env |
| } |
| if userConf.Cmd == nil || len(userConf.Cmd) == 0 { |
| userConf.Cmd = imageConf.Cmd |
| } |
| if userConf.Dns == nil || len(userConf.Dns) == 0 { |
| userConf.Dns = imageConf.Dns |
| } |
| } |
| |
| func (runtime *Runtime) Create(config *Config) (*Container, error) { |
| |
| // Lookup image |
| img, err := runtime.repositories.LookupImage(config.Image) |
| if err != nil { |
| return nil, err |
| } |
| |
| if img.Config != nil { |
| runtime.mergeConfig(config, img.Config) |
| } |
| |
| if config.Cmd == nil || len(config.Cmd) == 0 { |
| return nil, fmt.Errorf("No command specified") |
| } |
| |
| // Generate id |
| id := GenerateId() |
| // Generate default hostname |
| // FIXME: the lxc template no longer needs to set a default hostname |
| if config.Hostname == "" { |
| config.Hostname = id[:12] |
| } |
| |
| container := &Container{ |
| // FIXME: we should generate the ID here instead of receiving it as an argument |
| Id: id, |
| Created: time.Now(), |
| Path: config.Cmd[0], |
| Args: config.Cmd[1:], //FIXME: de-duplicate from config |
| Config: config, |
| Image: img.Id, // Always use the resolved image id |
| NetworkSettings: &NetworkSettings{}, |
| // FIXME: do we need to store this in the container? |
| SysInitPath: sysInitPath, |
| } |
| |
| container.root = runtime.containerRoot(container.Id) |
| // Step 1: create the container directory. |
| // This doubles as a barrier to avoid race conditions. |
| if err := os.Mkdir(container.root, 0700); err != nil { |
| return nil, err |
| } |
| |
| // If custom dns exists, then create a resolv.conf for the container |
| if len(config.Dns) > 0 { |
| container.ResolvConfPath = path.Join(container.root, "resolv.conf") |
| f, err := os.Create(container.ResolvConfPath) |
| if err != nil { |
| return nil, err |
| } |
| defer f.Close() |
| for _, dns := range config.Dns { |
| if _, err := f.Write([]byte("nameserver " + dns + "\n")); err != nil { |
| return nil, err |
| } |
| } |
| } else { |
| container.ResolvConfPath = "/etc/resolv.conf" |
| } |
| |
| // Step 2: save the container json |
| if err := container.ToDisk(); err != nil { |
| return nil, err |
| } |
| // Step 3: register the container |
| if err := runtime.Register(container); err != nil { |
| return nil, err |
| } |
| return container, nil |
| } |
| |
| func (runtime *Runtime) Load(id string) (*Container, error) { |
| container := &Container{root: runtime.containerRoot(id)} |
| if err := container.FromDisk(); err != nil { |
| return nil, err |
| } |
| if container.Id != id { |
| return container, fmt.Errorf("Container %s is stored at %s", container.Id, id) |
| } |
| if container.State.Running { |
| container.State.Ghost = true |
| } |
| if err := runtime.Register(container); err != nil { |
| return nil, err |
| } |
| return container, nil |
| } |
| |
| // Register makes a container object usable by the runtime as <container.Id> |
| func (runtime *Runtime) Register(container *Container) error { |
| if container.runtime != nil || runtime.Exists(container.Id) { |
| return fmt.Errorf("Container is already loaded") |
| } |
| if err := validateId(container.Id); err != nil { |
| return err |
| } |
| |
| // init the wait lock |
| container.waitLock = make(chan struct{}) |
| |
| // Even if not running, we init the lock (prevents races in start/stop/kill) |
| container.State.initLock() |
| |
| container.runtime = runtime |
| |
| // Attach to stdout and stderr |
| container.stderr = newWriteBroadcaster() |
| container.stdout = newWriteBroadcaster() |
| // Attach to stdin |
| if container.Config.OpenStdin { |
| container.stdin, container.stdinPipe = io.Pipe() |
| } else { |
| container.stdinPipe = NopWriteCloser(ioutil.Discard) // Silently drop stdin |
| } |
| // done |
| runtime.containers.PushBack(container) |
| runtime.idIndex.Add(container.Id) |
| |
| // When we actually restart, Start() do the monitoring. |
| // However, when we simply 'reattach', we have to restart a monitor |
| nomonitor := false |
| |
| // FIXME: if the container is supposed to be running but is not, auto restart it? |
| // if so, then we need to restart monitor and init a new lock |
| // If the container is supposed to be running, make sure of it |
| if container.State.Running { |
| if output, err := exec.Command("lxc-info", "-n", container.Id).CombinedOutput(); err != nil { |
| return err |
| } else { |
| if !strings.Contains(string(output), "RUNNING") { |
| Debugf("Container %s was supposed to be running be is not.", container.Id) |
| if runtime.autoRestart { |
| Debugf("Restarting") |
| container.State.Ghost = false |
| container.State.setStopped(0) |
| if err := container.Start(); err != nil { |
| return err |
| } |
| nomonitor = true |
| } else { |
| Debugf("Marking as stopped") |
| container.State.setStopped(-127) |
| if err := container.ToDisk(); err != nil { |
| return err |
| } |
| } |
| } |
| } |
| } |
| |
| // If the container is not running or just has been flagged not running |
| // then close the wait lock chan (will be reset upon start) |
| if !container.State.Running { |
| close(container.waitLock) |
| } else if !nomonitor { |
| container.allocateNetwork() |
| go container.monitor() |
| } |
| return nil |
| } |
| |
| func (runtime *Runtime) LogToDisk(src *writeBroadcaster, dst string) error { |
| log, err := os.OpenFile(dst, os.O_RDWR|os.O_APPEND|os.O_CREATE, 0600) |
| if err != nil { |
| return err |
| } |
| src.AddWriter(log) |
| return nil |
| } |
| |
| func (runtime *Runtime) Destroy(container *Container) error { |
| element := runtime.getContainerElement(container.Id) |
| if element == nil { |
| return fmt.Errorf("Container %v not found - maybe it was already destroyed?", container.Id) |
| } |
| |
| if err := container.Stop(10); err != nil { |
| return err |
| } |
| if mounted, err := container.Mounted(); err != nil { |
| return err |
| } else if mounted { |
| if err := container.Unmount(); err != nil { |
| return fmt.Errorf("Unable to unmount container %v: %v", container.Id, err) |
| } |
| } |
| // Deregister the container before removing its directory, to avoid race conditions |
| runtime.idIndex.Delete(container.Id) |
| runtime.containers.Remove(element) |
| if err := os.RemoveAll(container.root); err != nil { |
| return fmt.Errorf("Unable to remove filesystem for %v: %v", container.Id, err) |
| } |
| return nil |
| } |
| |
| // Commit creates a new filesystem image from the current state of a container. |
| // The image can optionally be tagged into a repository |
| func (runtime *Runtime) Commit(id, repository, tag, comment, author string, config *Config) (*Image, error) { |
| container := runtime.Get(id) |
| if container == nil { |
| return nil, fmt.Errorf("No such container: %s", id) |
| } |
| // FIXME: freeze the container before copying it to avoid data corruption? |
| // FIXME: this shouldn't be in commands. |
| rwTar, err := container.ExportRw() |
| if err != nil { |
| return nil, err |
| } |
| // Create a new image from the container's base layers + a new layer from container changes |
| img, err := runtime.graph.Create(rwTar, container, comment, author, config) |
| if err != nil { |
| return nil, err |
| } |
| // Register the image if needed |
| if repository != "" { |
| if err := runtime.repositories.Set(repository, tag, img.Id, true); err != nil { |
| return img, err |
| } |
| } |
| return img, nil |
| } |
| |
| func (runtime *Runtime) restore() error { |
| dir, err := ioutil.ReadDir(runtime.repository) |
| if err != nil { |
| return err |
| } |
| for _, v := range dir { |
| id := v.Name() |
| container, err := runtime.Load(id) |
| if err != nil { |
| Debugf("Failed to load container %v: %v", id, err) |
| continue |
| } |
| Debugf("Loaded container %v", container.Id) |
| } |
| return nil |
| } |
| |
| func (runtime *Runtime) UpdateCapabilities(quiet bool) { |
| if cgroupMemoryMountpoint, err := FindCgroupMountpoint("memory"); err != nil { |
| if !quiet { |
| log.Printf("WARNING: %s\n", err) |
| } |
| } else { |
| _, err1 := ioutil.ReadFile(path.Join(cgroupMemoryMountpoint, "memory.limit_in_bytes")) |
| _, err2 := ioutil.ReadFile(path.Join(cgroupMemoryMountpoint, "memory.soft_limit_in_bytes")) |
| runtime.capabilities.MemoryLimit = err1 == nil && err2 == nil |
| if !runtime.capabilities.MemoryLimit && !quiet { |
| log.Printf("WARNING: Your kernel does not support cgroup memory limit.") |
| } |
| |
| _, err = ioutil.ReadFile(path.Join(cgroupMemoryMountpoint, "memory.memsw.limit_in_bytes")) |
| runtime.capabilities.SwapLimit = err == nil |
| if !runtime.capabilities.SwapLimit && !quiet { |
| log.Printf("WARNING: Your kernel does not support cgroup swap limit.") |
| } |
| } |
| } |
| |
| // FIXME: harmonize with NewGraph() |
| func NewRuntime(autoRestart bool) (*Runtime, error) { |
| runtime, err := NewRuntimeFromDirectory("/var/lib/docker", autoRestart) |
| if err != nil { |
| return nil, err |
| } |
| |
| if k, err := GetKernelVersion(); err != nil { |
| log.Printf("WARNING: %s\n", err) |
| } else { |
| runtime.kernelVersion = k |
| if CompareKernelVersion(k, &KernelVersionInfo{Kernel: 3, Major: 8, Minor: 0}) < 0 { |
| log.Printf("WARNING: You are running linux kernel version %s, which might be unstable running docker. Please upgrade your kernel to 3.8.0.", k.String()) |
| } |
| } |
| runtime.UpdateCapabilities(false) |
| return runtime, nil |
| } |
| |
| func NewRuntimeFromDirectory(root string, autoRestart bool) (*Runtime, error) { |
| runtimeRepo := path.Join(root, "containers") |
| |
| if err := os.MkdirAll(runtimeRepo, 0700); err != nil && !os.IsExist(err) { |
| return nil, err |
| } |
| |
| g, err := NewGraph(path.Join(root, "graph")) |
| if err != nil { |
| return nil, err |
| } |
| volumes, err := NewGraph(path.Join(root, "volumes")) |
| if err != nil { |
| return nil, err |
| } |
| repositories, err := NewTagStore(path.Join(root, "repositories"), g) |
| if err != nil { |
| return nil, fmt.Errorf("Couldn't create Tag store: %s", err) |
| } |
| if NetworkBridgeIface == "" { |
| NetworkBridgeIface = DefaultNetworkBridge |
| } |
| netManager, err := newNetworkManager(NetworkBridgeIface) |
| if err != nil { |
| return nil, err |
| } |
| authConfig, err := auth.LoadConfig(root) |
| if err != nil && authConfig == nil { |
| // If the auth file does not exist, keep going |
| return nil, err |
| } |
| runtime := &Runtime{ |
| root: root, |
| repository: runtimeRepo, |
| containers: list.New(), |
| networkManager: netManager, |
| graph: g, |
| repositories: repositories, |
| authConfig: authConfig, |
| idIndex: NewTruncIndex(), |
| capabilities: &Capabilities{}, |
| autoRestart: autoRestart, |
| volumes: volumes, |
| } |
| |
| if err := runtime.restore(); err != nil { |
| return nil, err |
| } |
| return runtime, nil |
| } |
| |
| type History []*Container |
| |
| func (history *History) Len() int { |
| return len(*history) |
| } |
| |
| func (history *History) Less(i, j int) bool { |
| containers := *history |
| return containers[j].When().Before(containers[i].When()) |
| } |
| |
| func (history *History) Swap(i, j int) { |
| containers := *history |
| tmp := containers[i] |
| containers[i] = containers[j] |
| containers[j] = tmp |
| } |
| |
| func (history *History) Add(container *Container) { |
| *history = append(*history, container) |
| sort.Sort(history) |
| } |
