moby/daemon/commit.go
John Howard afd305c4b5 LCOW: Refactor to multiple layer-stores based on feedback
Signed-off-by: John Howard <jhoward@microsoft.com>
2018-01-18 08:31:05 -08:00

285 lines
7.5 KiB
Go

package daemon
import (
"encoding/json"
"fmt"
"io"
"runtime"
"strings"
"time"
"github.com/docker/distribution/reference"
"github.com/docker/docker/api/types/backend"
containertypes "github.com/docker/docker/api/types/container"
"github.com/docker/docker/builder/dockerfile"
"github.com/docker/docker/container"
"github.com/docker/docker/errdefs"
"github.com/docker/docker/image"
"github.com/docker/docker/layer"
"github.com/docker/docker/pkg/ioutils"
"github.com/pkg/errors"
)
// merge merges two Config, the image container configuration (defaults values),
// and the user container configuration, either passed by the API or generated
// by the cli.
// It will mutate the specified user configuration (userConf) with the image
// configuration where the user configuration is incomplete.
func merge(userConf, imageConf *containertypes.Config) error {
if userConf.User == "" {
userConf.User = imageConf.User
}
if len(userConf.ExposedPorts) == 0 {
userConf.ExposedPorts = imageConf.ExposedPorts
} else if imageConf.ExposedPorts != nil {
for port := range imageConf.ExposedPorts {
if _, exists := userConf.ExposedPorts[port]; !exists {
userConf.ExposedPorts[port] = struct{}{}
}
}
}
if len(userConf.Env) == 0 {
userConf.Env = imageConf.Env
} else {
for _, imageEnv := range imageConf.Env {
found := false
imageEnvKey := strings.Split(imageEnv, "=")[0]
for _, userEnv := range userConf.Env {
userEnvKey := strings.Split(userEnv, "=")[0]
if runtime.GOOS == "windows" {
// Case insensitive environment variables on Windows
imageEnvKey = strings.ToUpper(imageEnvKey)
userEnvKey = strings.ToUpper(userEnvKey)
}
if imageEnvKey == userEnvKey {
found = true
break
}
}
if !found {
userConf.Env = append(userConf.Env, imageEnv)
}
}
}
if userConf.Labels == nil {
userConf.Labels = map[string]string{}
}
for l, v := range imageConf.Labels {
if _, ok := userConf.Labels[l]; !ok {
userConf.Labels[l] = v
}
}
if len(userConf.Entrypoint) == 0 {
if len(userConf.Cmd) == 0 {
userConf.Cmd = imageConf.Cmd
userConf.ArgsEscaped = imageConf.ArgsEscaped
}
if userConf.Entrypoint == nil {
userConf.Entrypoint = imageConf.Entrypoint
}
}
if imageConf.Healthcheck != nil {
if userConf.Healthcheck == nil {
userConf.Healthcheck = imageConf.Healthcheck
} else {
if len(userConf.Healthcheck.Test) == 0 {
userConf.Healthcheck.Test = imageConf.Healthcheck.Test
}
if userConf.Healthcheck.Interval == 0 {
userConf.Healthcheck.Interval = imageConf.Healthcheck.Interval
}
if userConf.Healthcheck.Timeout == 0 {
userConf.Healthcheck.Timeout = imageConf.Healthcheck.Timeout
}
if userConf.Healthcheck.StartPeriod == 0 {
userConf.Healthcheck.StartPeriod = imageConf.Healthcheck.StartPeriod
}
if userConf.Healthcheck.Retries == 0 {
userConf.Healthcheck.Retries = imageConf.Healthcheck.Retries
}
}
}
if userConf.WorkingDir == "" {
userConf.WorkingDir = imageConf.WorkingDir
}
if len(userConf.Volumes) == 0 {
userConf.Volumes = imageConf.Volumes
} else {
for k, v := range imageConf.Volumes {
userConf.Volumes[k] = v
}
}
if userConf.StopSignal == "" {
userConf.StopSignal = imageConf.StopSignal
}
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 (daemon *Daemon) Commit(name string, c *backend.ContainerCommitConfig) (string, error) {
start := time.Now()
container, err := daemon.GetContainer(name)
if err != nil {
return "", err
}
// It is not possible to commit a running container on Windows
if (runtime.GOOS == "windows") && container.IsRunning() {
return "", errors.Errorf("%+v does not support commit of a running container", runtime.GOOS)
}
if container.IsDead() {
err := fmt.Errorf("You cannot commit container %s which is Dead", container.ID)
return "", errdefs.Conflict(err)
}
if container.IsRemovalInProgress() {
err := fmt.Errorf("You cannot commit container %s which is being removed", container.ID)
return "", errdefs.Conflict(err)
}
if c.Pause && !container.IsPaused() {
daemon.containerPause(container)
defer daemon.containerUnpause(container)
}
if c.MergeConfigs && c.Config == nil {
c.Config = container.Config
}
newConfig, err := dockerfile.BuildFromConfig(c.Config, c.Changes, container.OS)
if err != nil {
return "", err
}
if c.MergeConfigs {
if err := merge(newConfig, container.Config); err != nil {
return "", err
}
}
rwTar, err := daemon.exportContainerRw(container)
if err != nil {
return "", err
}
defer func() {
if rwTar != nil {
rwTar.Close()
}
}()
var parent *image.Image
if container.ImageID == "" {
parent = new(image.Image)
parent.RootFS = image.NewRootFS()
} else {
parent, err = daemon.imageStore.Get(container.ImageID)
if err != nil {
return "", err
}
}
l, err := daemon.layerStores[container.OS].Register(rwTar, parent.RootFS.ChainID())
if err != nil {
return "", err
}
defer layer.ReleaseAndLog(daemon.layerStores[container.OS], l)
containerConfig := c.ContainerConfig
if containerConfig == nil {
containerConfig = container.Config
}
cc := image.ChildConfig{
ContainerID: container.ID,
Author: c.Author,
Comment: c.Comment,
ContainerConfig: containerConfig,
Config: newConfig,
DiffID: l.DiffID(),
}
config, err := json.Marshal(image.NewChildImage(parent, cc, container.OS))
if err != nil {
return "", err
}
id, err := daemon.imageStore.Create(config)
if err != nil {
return "", err
}
if container.ImageID != "" {
if err := daemon.imageStore.SetParent(id, container.ImageID); err != nil {
return "", err
}
}
imageRef := ""
if c.Repo != "" {
newTag, err := reference.ParseNormalizedNamed(c.Repo) // todo: should move this to API layer
if err != nil {
return "", err
}
if !reference.IsNameOnly(newTag) {
return "", errors.Errorf("unexpected repository name: %s", c.Repo)
}
if c.Tag != "" {
if newTag, err = reference.WithTag(newTag, c.Tag); err != nil {
return "", err
}
}
if err := daemon.TagImageWithReference(id, newTag); err != nil {
return "", err
}
imageRef = reference.FamiliarString(newTag)
}
attributes := map[string]string{
"comment": c.Comment,
"imageID": id.String(),
"imageRef": imageRef,
}
daemon.LogContainerEventWithAttributes(container, "commit", attributes)
containerActions.WithValues("commit").UpdateSince(start)
return id.String(), nil
}
func (daemon *Daemon) exportContainerRw(container *container.Container) (arch io.ReadCloser, err error) {
rwlayer, err := daemon.layerStores[container.OS].GetRWLayer(container.ID)
if err != nil {
return nil, err
}
defer func() {
if err != nil {
daemon.layerStores[container.OS].ReleaseRWLayer(rwlayer)
}
}()
// TODO: this mount call is not necessary as we assume that TarStream() should
// mount the layer if needed. But the Diff() function for windows requests that
// the layer should be mounted when calling it. So we reserve this mount call
// until windows driver can implement Diff() interface correctly.
_, err = rwlayer.Mount(container.GetMountLabel())
if err != nil {
return nil, err
}
archive, err := rwlayer.TarStream()
if err != nil {
rwlayer.Unmount()
return nil, err
}
return ioutils.NewReadCloserWrapper(archive, func() error {
archive.Close()
err = rwlayer.Unmount()
daemon.layerStores[container.OS].ReleaseRWLayer(rwlayer)
return err
}),
nil
}