func (b *Builder) processImageFrom(img *image.Image) error {
b.image = img.ID().String()
if img.Config != nil {
b.runConfig = img.Config
}
// The default path will be blank on Windows (set by HCS)
if len(b.runConfig.Env) == 0 && container.DefaultPathEnv != "" {
b.runConfig.Env = append(b.runConfig.Env, "PATH="+container.DefaultPathEnv)
}
// Process ONBUILD triggers if they exist
if nTriggers := len(b.runConfig.OnBuild); nTriggers != 0 {
word := "trigger"
if nTriggers > 1 {
word = "triggers"
}
fmt.Fprintf(b.Stderr, "# Executing %d build %s...\n", nTriggers, word)
}
// Copy the ONBUILD triggers, and remove them from the config, since the config will be committed.
onBuildTriggers := b.runConfig.OnBuild
b.runConfig.OnBuild = []string{}
// parse the ONBUILD triggers by invoking the parser
for _, step := range onBuildTriggers {
ast, err := parser.Parse(strings.NewReader(step))
if err != nil {
return err
}
for i, n := range ast.Children {
switch strings.ToUpper(n.Value) {
case "ONBUILD":
return fmt.Errorf("Chaining ONBUILD via `ONBUILD ONBUILD` isn't allowed")
case "MAINTAINER", "FROM":
return fmt.Errorf("%s isn't allowed as an ONBUILD trigger", n.Value)
}
if err := b.dispatch(i, n); err != nil {
return err
}
}
}
return nil
}
func (ic *imageCache) GetCache(parentID string, cfg *containertypes.Config) (string, error) {
imgID, err := ic.localImageCache.GetCache(parentID, cfg)
if err != nil {
return "", err
}
if imgID != "" {
for _, s := range ic.sources {
if ic.isParent(s.ID(), image.ID(imgID)) {
return imgID, nil
}
}
}
var parent *image.Image
lenHistory := 0
if parentID != "" {
parent, err = ic.daemon.imageStore.Get(image.ID(parentID))
if err != nil {
return "", errors.Wrapf(err, "unable to find image %v", parentID)
}
lenHistory = len(parent.History)
}
for _, target := range ic.sources {
if !isValidParent(target, parent) || !isValidConfig(cfg, target.History[lenHistory]) {
continue
}
if len(target.History)-1 == lenHistory { // last
if parent != nil {
if err := ic.daemon.imageStore.SetParent(target.ID(), parent.ID()); err != nil {
return "", errors.Wrapf(err, "failed to set parent for %v to %v", target.ID(), parent.ID())
}
}
return target.ID().String(), nil
}
imgID, err := ic.restoreCachedImage(parent, target, cfg)
if err != nil {
return "", errors.Wrapf(err, "failed to restore cached image from %q to %v", parentID, target.ID())
}
ic.sources = []*image.Image{target} // avoid jumping to different target, tuned for safety atm
return imgID.String(), nil
}
return "", nil
}
func newImage(image *image.Image, size int64) *types.Image {
newImage := new(types.Image)
newImage.ParentID = image.Parent.String()
newImage.ID = image.ID().String()
newImage.Created = image.Created.Unix()
newImage.Size = size
newImage.VirtualSize = size
if image.Config != nil {
newImage.Labels = image.Config.Labels
}
return newImage
}
func newImage(image *image.Image, virtualSize int64) *types.ImageSummary {
newImage := new(types.ImageSummary)
newImage.ParentID = image.Parent.String()
newImage.ID = image.ID().String()
newImage.Created = image.Created.Unix()
newImage.Size = -1
newImage.VirtualSize = virtualSize
newImage.SharedSize = -1
newImage.Containers = -1
if image.Config != nil {
newImage.Labels = image.Config.Labels
}
return newImage
}
func (ic *imageCache) restoreCachedImage(parent, target *image.Image, cfg *containertypes.Config) (image.ID, error) {
var history []image.History
rootFS := image.NewRootFS()
lenHistory := 0
if parent != nil {
history = parent.History
rootFS = parent.RootFS
lenHistory = len(parent.History)
}
history = append(history, target.History[lenHistory])
if layer := getLayerForHistoryIndex(target, lenHistory); layer != "" {
rootFS.Append(layer)
}
config, err := json.Marshal(&image.Image{
V1Image: image.V1Image{
DockerVersion: dockerversion.Version,
Config: cfg,
Architecture: target.Architecture,
OS: target.OS,
Author: target.Author,
Created: history[len(history)-1].Created,
},
RootFS: rootFS,
History: history,
OSFeatures: target.OSFeatures,
OSVersion: target.OSVersion,
})
if err != nil {
return "", errors.Wrap(err, "failed to marshal image config")
}
imgID, err := ic.daemon.imageStore.Create(config)
if err != nil {
return "", errors.Wrap(err, "failed to create cache image")
}
if parent != nil {
if err := ic.daemon.imageStore.SetParent(imgID, parent.ID()); err != nil {
return "", errors.Wrapf(err, "failed to set parent for %v to %v", target.ID(), parent.ID())
}
}
return imgID, nil
}
// Create creates a new container from the given configuration with a given name.
func (daemon *Daemon) create(params types.ContainerCreateConfig) (retC *container.Container, retErr error) {
var (
container *container.Container
img *image.Image
imgID image.ID
err error
)
if params.Config.Image != "" {
img, err = daemon.GetImage(params.Config.Image)
if err != nil {
return nil, err
}
imgID = img.ID()
}
if err := daemon.mergeAndVerifyConfig(params.Config, img); err != nil {
return nil, err
}
if err := daemon.mergeAndVerifyLogConfig(¶ms.HostConfig.LogConfig); err != nil {
return nil, err
}
if container, err = daemon.newContainer(params.Name, params.Config, imgID); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.cleanupContainer(container, true); err != nil {
logrus.Errorf("failed to cleanup container on create error: %v", err)
}
}
}()
if err := daemon.setSecurityOptions(container, params.HostConfig); err != nil {
return nil, err
}
container.HostConfig.StorageOpt = params.HostConfig.StorageOpt
// Set RWLayer for container after mount labels have been set
if err := daemon.setRWLayer(container); err != nil {
return nil, err
}
rootUID, rootGID, err := idtools.GetRootUIDGID(daemon.uidMaps, daemon.gidMaps)
if err != nil {
return nil, err
}
if err := idtools.MkdirAs(container.Root, 0700, rootUID, rootGID); err != nil {
return nil, err
}
if err := daemon.setHostConfig(container, params.HostConfig); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.removeMountPoints(container, true); err != nil {
logrus.Error(err)
}
}
}()
if err := daemon.createContainerPlatformSpecificSettings(container, params.Config, params.HostConfig); err != nil {
return nil, err
}
var endpointsConfigs map[string]*networktypes.EndpointSettings
if params.NetworkingConfig != nil {
endpointsConfigs = params.NetworkingConfig.EndpointsConfig
}
if err := daemon.updateContainerNetworkSettings(container, endpointsConfigs); err != nil {
return nil, err
}
if err := container.ToDisk(); err != nil {
logrus.Errorf("Error saving new container to disk: %v", err)
return nil, err
}
if err := daemon.Register(container); err != nil {
return nil, err
}
daemon.LogContainerEvent(container, "create")
return container, nil
}
// Create creates a new container from the given configuration with a given name.
func (daemon *Daemon) create(params types.ContainerCreateConfig, managed bool) (retC *container.Container, retErr error) {
var (
container *container.Container
img *image.Image
imgID image.ID
err error
)
if params.Config.Image != "" {
img, err = daemon.GetImage(params.Config.Image)
if err != nil {
return nil, err
}
imgID = img.ID()
}
if err := daemon.mergeAndVerifyConfig(params.Config, img); err != nil {
return nil, err
}
if err := daemon.mergeAndVerifyLogConfig(¶ms.HostConfig.LogConfig); err != nil {
return nil, err
}
if container, err = daemon.newContainer(params.Name, params.Config, imgID, managed); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.cleanupContainer(container, true, true); err != nil {
logrus.Errorf("failed to cleanup container on create error: %v", err)
}
}
}()
if err := daemon.setSecurityOptions(container, params.HostConfig); err != nil {
return nil, err
}
container.HostConfig.StorageOpt = params.HostConfig.StorageOpt
// Set RWLayer for container after mount labels have been set
if err := daemon.setRWLayer(container); err != nil {
return nil, err
}
rootUID, rootGID, err := idtools.GetRootUIDGID(daemon.uidMaps, daemon.gidMaps)
if err != nil {
return nil, err
}
if err := idtools.MkdirAs(container.Root, 0700, rootUID, rootGID); err != nil {
return nil, err
}
if err := idtools.MkdirAs(container.CheckpointDir(), 0700, rootUID, rootGID); err != nil {
return nil, err
}
if err := daemon.setHostConfig(container, params.HostConfig); err != nil {
return nil, err
}
if err := daemon.createContainerPlatformSpecificSettings(container, params.Config, params.HostConfig); err != nil {
return nil, err
}
var endpointsConfigs map[string]*networktypes.EndpointSettings
if params.NetworkingConfig != nil {
endpointsConfigs = params.NetworkingConfig.EndpointsConfig
}
// Make sure NetworkMode has an acceptable value. We do this to ensure
// backwards API compatibility.
container.HostConfig = runconfig.SetDefaultNetModeIfBlank(container.HostConfig)
daemon.updateContainerNetworkSettings(container, endpointsConfigs)
if err := container.ToDisk(); err != nil {
logrus.Errorf("Error saving new container to disk: %v", err)
return nil, err
}
if err := daemon.Register(container); err != nil {
return nil, err
}
daemon.LogContainerEvent(container, "create")
return container, nil
}
// Create creates a new container from the given configuration with a given name.
func (daemon *Daemon) create(params *ContainerCreateConfig) (retC *container.Container, retErr error) {
var (
container *container.Container
img *image.Image
imgID image.ID
err error
)
if params.Config.Image != "" {
img, err = daemon.GetImage(params.Config.Image)
if err != nil {
return nil, err
}
imgID = img.ID()
}
if err := daemon.mergeAndVerifyConfig(params.Config, img); err != nil {
return nil, err
}
if container, err = daemon.newContainer(params.Name, params.Config, imgID); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.ContainerRm(container.ID, &ContainerRmConfig{ForceRemove: true}); err != nil {
logrus.Errorf("Clean up Error! Cannot destroy container %s: %v", container.ID, err)
}
}
}()
if err := daemon.Register(container); err != nil {
return nil, err
}
rootUID, rootGID, err := idtools.GetRootUIDGID(daemon.uidMaps, daemon.gidMaps)
if err != nil {
return nil, err
}
if err := idtools.MkdirAs(container.Root, 0700, rootUID, rootGID); err != nil {
return nil, err
}
if err := daemon.setHostConfig(container, params.HostConfig); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.removeMountPoints(container, true); err != nil {
logrus.Error(err)
}
}
}()
if err := daemon.createContainerPlatformSpecificSettings(container, params.Config, params.HostConfig, img); err != nil {
return nil, err
}
if err := container.ToDiskLocking(); err != nil {
logrus.Errorf("Error saving new container to disk: %v", err)
return nil, err
}
daemon.LogContainerEvent(container, "create")
return container, nil
}
// Create creates a new container from the given configuration with a given name.
func (daemon *Daemon) create(params types.ContainerCreateConfig) (retC *container.Container, retErr error) {
var (
container *container.Container
img *image.Image
imgID image.ID
err error
)
if params.Config.Image != "" {
img, err = daemon.GetImage(params.Config.Image)
if err != nil {
return nil, err
}
imgID = img.ID()
}
if err := daemon.mergeAndVerifyConfig(params.Config, img); err != nil {
return nil, err
}
if container, err = daemon.newContainer(params.Name, params.Config, imgID); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.ContainerRm(container.ID, &types.ContainerRmConfig{ForceRemove: true}); err != nil {
logrus.Errorf("Clean up Error! Cannot destroy container %s: %v", container.ID, err)
}
}
}()
logCfg := container.GetLogConfig(daemon.defaultLogConfig)
if err := logger.ValidateLogOpts(logCfg.Type, logCfg.Config); err != nil {
return nil, err
}
if err := daemon.setSecurityOptions(container, params.HostConfig); err != nil {
return nil, err
}
// Set RWLayer for container after mount labels have been set
if err := daemon.setRWLayer(container); err != nil {
return nil, err
}
if err := daemon.Register(container); err != nil {
return nil, err
}
rootUID, rootGID, err := idtools.GetRootUIDGID(daemon.uidMaps, daemon.gidMaps)
if err != nil {
return nil, err
}
if err := idtools.MkdirAs(container.Root, 0700, rootUID, rootGID); err != nil {
return nil, err
}
if err := daemon.setHostConfig(container, params.HostConfig); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.removeMountPoints(container, true); err != nil {
logrus.Error(err)
}
}
}()
if err := daemon.createContainerPlatformSpecificSettings(container, params.Config, params.HostConfig); err != nil {
return nil, err
}
var endpointsConfigs map[string]*networktypes.EndpointSettings
if params.NetworkingConfig != nil {
endpointsConfigs = params.NetworkingConfig.EndpointsConfig
}
if err := daemon.updateContainerNetworkSettings(container, endpointsConfigs); err != nil {
return nil, err
}
if err := container.ToDiskLocking(); err != nil {
logrus.Errorf("Error saving new container to disk: %v", err)
return nil, err
}
daemon.LogContainerEvent(container, "create")
return container, nil
}
func getImageIDAndError(img *image.Image, err error) (string, error) {
if img == nil || err != nil {
return "", err
}
return img.ID().String(), nil
}
// Create creates a new container from the given configuration with a given name.
func (daemon *Daemon) create(params types.ContainerCreateConfig) (retC *container.Container, retErr error) {
var (
container *container.Container
img *image.Image
imgID image.ID
err error
)
if params.Config.Image != "" {
//获取镜像
img, err = daemon.GetImage(params.Config.Image)
if err != nil {
return nil, err
}
//获取镜像ID号
imgID = img.ID()
}
//合并并且检查参数
if err := daemon.mergeAndVerifyConfig(params.Config, img); err != nil {
return nil, err
}
//创建一个新的容器，此时需要跟踪分析newContainer方法，该方法在daemon/daemon.go中。
//该方法返回的是container，是一个这样的结构：
/*
type Container struct {
//这是通用的参数
CommonContainer
// 这个是平台特殊的参数，只在类unix系统上有意义。
AppArmorProfile string
HostnamePath string
HostsPath string
ShmPath string
ResolvConfPath string
SeccompProfile string
NoNewPrivileges bool
}
*/
//创建容器实例，实际上只是在代码中创建，并没有创建文件系统和namespace。
//实际上，创建容器的过程中最多也就创建到文件系统，namespace只有在容器
//运行时候才会生效。
if container, err = daemon.newContainer(params.Name, params.Config, imgID); err != nil {
return nil, err
}
//如果创建容器出错，就试图删除容器。
defer func() {
if retErr != nil {
if err := daemon.ContainerRm(container.ID, &types.ContainerRmConfig{ForceRemove: true}); err != nil {
logrus.Errorf("Clean up Error! Cannot destroy container %s: %v", container.ID, err)
}
}
}()
//配置容器的安全设置，例如apparmor,selinux等。
if err := daemon.setSecurityOptions(container, params.HostConfig); err != nil {
return nil, err
}
// Set RWLayer for container after mount labels have been set
// 设置可读写层，就是获取layID等信息,包括镜像层、容器层。
//详情请见setRWLayer函数，就在本文件中。
if err := daemon.setRWLayer(container); err != nil {
return nil, err
}
//向daemon注册容器：
//daemon.containers.Add(c.ID, c)
if err := daemon.Register(container); err != nil {
return nil, err
}
rootUID, rootGID, err := idtools.GetRootUIDGID(daemon.uidMaps, daemon.gidMaps)
if err != nil {
return nil, err
}
//设置容器root目录（元数据目录/var/lib/docker/containers）的权限。
if err := idtools.MkdirAs(container.Root, 0700, rootUID, rootGID); err != nil {
return nil, err
}
//这个方法主要做两件事情：
//挂载volumes;
//设置容器之间的链接links；
if err := daemon.setHostConfig(container, params.HostConfig); err != nil {
return nil, err
}
defer func() {
if retErr != nil {
if err := daemon.removeMountPoints(container, true); err != nil {
logrus.Error(err)
}
}
}()
//这一步是处理和平台相关的操作，具体在daemon/create_unix.go文件中
/*
func (daemon *Daemon) createContainerPlatformSpecificSettings(container *container.Container, config *containertypes.Config, hostConfig *containertypes.HostConfig) error {
if err := daemon.Mount(container); err != nil {
return err
}
defer daemon.Unmount(container)
rootUID, rootGID := daemon.GetRemappedUIDGID()
if err := container.SetupWorkingDirectory(rootUID, rootGID); err != nil {
return err
}
for spec := range config.Volumes {
name := stringid.GenerateNonCryptoID()
destination := filepath.Clean(spec)
// Skip volumes for which we already have something mounted on that
// destination because of a --volume-from.
if container.IsDestinationMounted(destination) {
continue
}
path, err := container.GetResourcePath(destination)
if err != nil {
return err
}
stat, err := os.Stat(path)
if err == nil && !stat.IsDir() {
return fmt.Errorf("cannot mount volume over existing file, file exists %s", path)
}
v, err := daemon.volumes.CreateWithRef(name, hostConfig.VolumeDriver, container.ID, nil, nil)
if err != nil {
return err
}
if err := label.Relabel(v.Path(), container.MountLabel, true); err != nil {
return err
}
container.AddMountPointWithVolume(destination, v, true)
}
return daemon.populateVolumes(container)
}
*/
//在这一步骤里面进行一些跟平台相关的设置，主要为mount目录文件，以及volume挂载。
if err := daemon.createContainerPlatformSpecificSettings(container, params.Config, params.HostConfig); err != nil {
return nil, err
}
//网络endpoints的配置
var endpointsConfigs map[string]*networktypes.EndpointSettings
if params.NetworkingConfig != nil {
endpointsConfigs = params.NetworkingConfig.EndpointsConfig
}
//更新网路配置，在daemon/container_operations.go中，调用了libnetwork模块，需要仔细研究。
//这里仅仅是更新container.NetworkSettings.Networks[]数组中的网络模式。并没有真正创建网络。
if err := daemon.updateContainerNetworkSettings(container, endpointsConfigs); err != nil {
return nil, err
}
//将容器的配置保存到磁盘。但是这个和另外一个todisk的区别是什么？
if err := container.ToDiskLocking(); err != nil {
logrus.Errorf("Error saving new container to disk: %v", err)
return nil, err
}
//记录容器的事件日志。
daemon.LogContainerEvent(container, "create")
return container, nil
}