moby/layer/filestore.go
Derek McGowan caef48f4e2 Add more robust error handling on layer store creation
Add continue when layer fails on store creation
Trim whitespace from layerstore files to keep trailing space from failing a layer load

Fixes #19449

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)
2016-01-19 11:17:08 -08:00

326 lines
8.1 KiB
Go

package layer
import (
"compress/gzip"
"errors"
"fmt"
"io"
"io/ioutil"
"os"
"path/filepath"
"regexp"
"strconv"
"strings"
"github.com/Sirupsen/logrus"
"github.com/docker/distribution/digest"
"github.com/docker/docker/pkg/ioutils"
)
var (
stringIDRegexp = regexp.MustCompile(`^[a-f0-9]{64}(-init)?$`)
supportedAlgorithms = []digest.Algorithm{
digest.SHA256,
// digest.SHA384, // Currently not used
// digest.SHA512, // Currently not used
}
)
type fileMetadataStore struct {
root string
}
type fileMetadataTransaction struct {
store *fileMetadataStore
root string
}
// NewFSMetadataStore returns an instance of a metadata store
// which is backed by files on disk using the provided root
// as the root of metadata files.
func NewFSMetadataStore(root string) (MetadataStore, error) {
if err := os.MkdirAll(root, 0700); err != nil {
return nil, err
}
return &fileMetadataStore{
root: root,
}, nil
}
func (fms *fileMetadataStore) getLayerDirectory(layer ChainID) string {
dgst := digest.Digest(layer)
return filepath.Join(fms.root, string(dgst.Algorithm()), dgst.Hex())
}
func (fms *fileMetadataStore) getLayerFilename(layer ChainID, filename string) string {
return filepath.Join(fms.getLayerDirectory(layer), filename)
}
func (fms *fileMetadataStore) getMountDirectory(mount string) string {
return filepath.Join(fms.root, "mounts", mount)
}
func (fms *fileMetadataStore) getMountFilename(mount, filename string) string {
return filepath.Join(fms.getMountDirectory(mount), filename)
}
func (fms *fileMetadataStore) StartTransaction() (MetadataTransaction, error) {
tmpDir := filepath.Join(fms.root, "tmp")
if err := os.MkdirAll(tmpDir, 0755); err != nil {
return nil, err
}
td, err := ioutil.TempDir(tmpDir, "layer-")
if err != nil {
return nil, err
}
// Create a new tempdir
return &fileMetadataTransaction{
store: fms,
root: td,
}, nil
}
func (fm *fileMetadataTransaction) SetSize(size int64) error {
content := fmt.Sprintf("%d", size)
return ioutil.WriteFile(filepath.Join(fm.root, "size"), []byte(content), 0644)
}
func (fm *fileMetadataTransaction) SetParent(parent ChainID) error {
return ioutil.WriteFile(filepath.Join(fm.root, "parent"), []byte(digest.Digest(parent).String()), 0644)
}
func (fm *fileMetadataTransaction) SetDiffID(diff DiffID) error {
return ioutil.WriteFile(filepath.Join(fm.root, "diff"), []byte(digest.Digest(diff).String()), 0644)
}
func (fm *fileMetadataTransaction) SetCacheID(cacheID string) error {
return ioutil.WriteFile(filepath.Join(fm.root, "cache-id"), []byte(cacheID), 0644)
}
func (fm *fileMetadataTransaction) TarSplitWriter(compressInput bool) (io.WriteCloser, error) {
f, err := os.OpenFile(filepath.Join(fm.root, "tar-split.json.gz"), os.O_TRUNC|os.O_CREATE|os.O_WRONLY, 0644)
if err != nil {
return nil, err
}
var wc io.WriteCloser
if compressInput {
wc = gzip.NewWriter(f)
} else {
wc = f
}
return ioutils.NewWriteCloserWrapper(wc, func() error {
wc.Close()
return f.Close()
}), nil
}
func (fm *fileMetadataTransaction) Commit(layer ChainID) error {
finalDir := fm.store.getLayerDirectory(layer)
if err := os.MkdirAll(filepath.Dir(finalDir), 0755); err != nil {
return err
}
return os.Rename(fm.root, finalDir)
}
func (fm *fileMetadataTransaction) Cancel() error {
return os.RemoveAll(fm.root)
}
func (fm *fileMetadataTransaction) String() string {
return fm.root
}
func (fms *fileMetadataStore) GetSize(layer ChainID) (int64, error) {
content, err := ioutil.ReadFile(fms.getLayerFilename(layer, "size"))
if err != nil {
return 0, err
}
size, err := strconv.ParseInt(string(content), 10, 64)
if err != nil {
return 0, err
}
return size, nil
}
func (fms *fileMetadataStore) GetParent(layer ChainID) (ChainID, error) {
content, err := ioutil.ReadFile(fms.getLayerFilename(layer, "parent"))
if err != nil {
if os.IsNotExist(err) {
return "", nil
}
return "", err
}
dgst, err := digest.ParseDigest(strings.TrimSpace(string(content)))
if err != nil {
return "", err
}
return ChainID(dgst), nil
}
func (fms *fileMetadataStore) GetDiffID(layer ChainID) (DiffID, error) {
content, err := ioutil.ReadFile(fms.getLayerFilename(layer, "diff"))
if err != nil {
return "", err
}
dgst, err := digest.ParseDigest(strings.TrimSpace(string(content)))
if err != nil {
return "", err
}
return DiffID(dgst), nil
}
func (fms *fileMetadataStore) GetCacheID(layer ChainID) (string, error) {
contentBytes, err := ioutil.ReadFile(fms.getLayerFilename(layer, "cache-id"))
if err != nil {
return "", err
}
content := strings.TrimSpace(string(contentBytes))
if !stringIDRegexp.MatchString(content) {
return "", errors.New("invalid cache id value")
}
return content, nil
}
func (fms *fileMetadataStore) TarSplitReader(layer ChainID) (io.ReadCloser, error) {
fz, err := os.Open(fms.getLayerFilename(layer, "tar-split.json.gz"))
if err != nil {
return nil, err
}
f, err := gzip.NewReader(fz)
if err != nil {
return nil, err
}
return ioutils.NewReadCloserWrapper(f, func() error {
f.Close()
return fz.Close()
}), nil
}
func (fms *fileMetadataStore) SetMountID(mount string, mountID string) error {
if err := os.MkdirAll(fms.getMountDirectory(mount), 0755); err != nil {
return err
}
return ioutil.WriteFile(fms.getMountFilename(mount, "mount-id"), []byte(mountID), 0644)
}
func (fms *fileMetadataStore) SetInitID(mount string, init string) error {
if err := os.MkdirAll(fms.getMountDirectory(mount), 0755); err != nil {
return err
}
return ioutil.WriteFile(fms.getMountFilename(mount, "init-id"), []byte(init), 0644)
}
func (fms *fileMetadataStore) SetMountParent(mount string, parent ChainID) error {
if err := os.MkdirAll(fms.getMountDirectory(mount), 0755); err != nil {
return err
}
return ioutil.WriteFile(fms.getMountFilename(mount, "parent"), []byte(digest.Digest(parent).String()), 0644)
}
func (fms *fileMetadataStore) GetMountID(mount string) (string, error) {
contentBytes, err := ioutil.ReadFile(fms.getMountFilename(mount, "mount-id"))
if err != nil {
return "", err
}
content := strings.TrimSpace(string(contentBytes))
if !stringIDRegexp.MatchString(content) {
return "", errors.New("invalid mount id value")
}
return content, nil
}
func (fms *fileMetadataStore) GetInitID(mount string) (string, error) {
contentBytes, err := ioutil.ReadFile(fms.getMountFilename(mount, "init-id"))
if err != nil {
if os.IsNotExist(err) {
return "", nil
}
return "", err
}
content := strings.TrimSpace(string(contentBytes))
if !stringIDRegexp.MatchString(content) {
return "", errors.New("invalid init id value")
}
return content, nil
}
func (fms *fileMetadataStore) GetMountParent(mount string) (ChainID, error) {
content, err := ioutil.ReadFile(fms.getMountFilename(mount, "parent"))
if err != nil {
if os.IsNotExist(err) {
return "", nil
}
return "", err
}
dgst, err := digest.ParseDigest(strings.TrimSpace(string(content)))
if err != nil {
return "", err
}
return ChainID(dgst), nil
}
func (fms *fileMetadataStore) List() ([]ChainID, []string, error) {
var ids []ChainID
for _, algorithm := range supportedAlgorithms {
fileInfos, err := ioutil.ReadDir(filepath.Join(fms.root, string(algorithm)))
if err != nil {
if os.IsNotExist(err) {
continue
}
return nil, nil, err
}
for _, fi := range fileInfos {
if fi.IsDir() && fi.Name() != "mounts" {
dgst := digest.NewDigestFromHex(string(algorithm), fi.Name())
if err := dgst.Validate(); err != nil {
logrus.Debugf("Ignoring invalid digest %s:%s", algorithm, fi.Name())
} else {
ids = append(ids, ChainID(dgst))
}
}
}
}
fileInfos, err := ioutil.ReadDir(filepath.Join(fms.root, "mounts"))
if err != nil {
if os.IsNotExist(err) {
return ids, []string{}, nil
}
return nil, nil, err
}
var mounts []string
for _, fi := range fileInfos {
if fi.IsDir() {
mounts = append(mounts, fi.Name())
}
}
return ids, mounts, nil
}
func (fms *fileMetadataStore) Remove(layer ChainID) error {
return os.RemoveAll(fms.getLayerDirectory(layer))
}
func (fms *fileMetadataStore) RemoveMount(mount string) error {
return os.RemoveAll(fms.getMountDirectory(mount))
}