distribution/client/client.go
Stephen J Day 7b56d10076 Lock down HTTP API error codes
This commit locks down the set of http error codes that will be part of the
inital V2 specification, proposed in docker/docker#9015. The naming order has
been slightly changed and there are few tweaks to ensure all conditions are
captured but this will be set the docker core will be impleemnted against.

To support this, the errors have been moved into an api/errors package. A new
type, ErrorDescriptor, has been defined to centralize the code, message and
definitions used with each type. The information therein can be used to
generate documentation and response code mappings (yet to come...).

In addition to the refactoring that came along with this change, several tests
have been added to ensure serialization round trips are reliable. This allows
better support for using these error types on the client and server side. This
is coupled with some tweaks in the client code to fix issues with error
reporting.

Other fixes in the client include moving client-specific errors out of the base
package and ensuring that we have correct parameters for finishing uploads.
2014-12-10 11:49:04 -08:00

540 lines
15 KiB
Go

package client
import (
"bytes"
"encoding/json"
"fmt"
"io"
"net/http"
"net/url"
"regexp"
"strconv"
"github.com/docker/docker-registry/api/errors"
"github.com/docker/docker-registry/digest"
"github.com/docker/docker-registry/storage"
)
// Client implements the client interface to the registry http api
type Client interface {
// GetImageManifest returns an image manifest for the image at the given
// name, tag pair.
GetImageManifest(name, tag string) (*storage.SignedManifest, error)
// PutImageManifest uploads an image manifest for the image at the given
// name, tag pair.
PutImageManifest(name, tag string, imageManifest *storage.SignedManifest) error
// DeleteImage removes the image at the given name, tag pair.
DeleteImage(name, tag string) error
// ListImageTags returns a list of all image tags with the given repository
// name.
ListImageTags(name string) ([]string, error)
// BlobLength returns the length of the blob stored at the given name,
// digest pair.
// Returns a length value of -1 on error or if the blob does not exist.
BlobLength(name string, dgst digest.Digest) (int, error)
// GetBlob returns the blob stored at the given name, digest pair in the
// form of an io.ReadCloser with the length of this blob.
// A nonzero byteOffset can be provided to receive a partial blob beginning
// at the given offset.
GetBlob(name string, dgst digest.Digest, byteOffset int) (io.ReadCloser, int, error)
// InitiateBlobUpload starts a blob upload in the given repository namespace
// and returns a unique location url to use for other blob upload methods.
InitiateBlobUpload(name string) (string, error)
// GetBlobUploadStatus returns the byte offset and length of the blob at the
// given upload location.
GetBlobUploadStatus(location string) (int, int, error)
// UploadBlob uploads a full blob to the registry.
UploadBlob(location string, blob io.ReadCloser, length int, dgst digest.Digest) error
// UploadBlobChunk uploads a blob chunk with a given length and startByte to
// the registry.
// FinishChunkedBlobUpload must be called to finalize this upload.
UploadBlobChunk(location string, blobChunk io.ReadCloser, length, startByte int) error
// FinishChunkedBlobUpload completes a chunked blob upload at a given
// location.
FinishChunkedBlobUpload(location string, length int, dgst digest.Digest) error
// CancelBlobUpload deletes all content at the unfinished blob upload
// location and invalidates any future calls to this blob upload.
CancelBlobUpload(location string) error
}
// New returns a new Client which operates against a registry with the
// given base endpoint
// This endpoint should not include /v2/ or any part of the url after this.
func New(endpoint string) Client {
return &clientImpl{endpoint}
}
// clientImpl is the default implementation of the Client interface
type clientImpl struct {
Endpoint string
}
// TODO(bbland): use consistent route generation between server and client
func (r *clientImpl) GetImageManifest(name, tag string) (*storage.SignedManifest, error) {
response, err := http.Get(r.imageManifestURL(name, tag))
if err != nil {
return nil, err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusOK:
break
case response.StatusCode == http.StatusNotFound:
return nil, &ImageManifestNotFoundError{Name: name, Tag: tag}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return nil, err
}
return nil, &errs
default:
return nil, &UnexpectedHTTPStatusError{Status: response.Status}
}
decoder := json.NewDecoder(response.Body)
manifest := new(storage.SignedManifest)
err = decoder.Decode(manifest)
if err != nil {
return nil, err
}
return manifest, nil
}
func (r *clientImpl) PutImageManifest(name, tag string, manifest *storage.SignedManifest) error {
putRequest, err := http.NewRequest("PUT",
r.imageManifestURL(name, tag), bytes.NewReader(manifest.Raw))
if err != nil {
return err
}
response, err := http.DefaultClient.Do(putRequest)
if err != nil {
return err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusOK:
return nil
case response.StatusCode >= 400 && response.StatusCode < 500:
var errors errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errors)
if err != nil {
return err
}
return &errors
default:
return &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) DeleteImage(name, tag string) error {
deleteRequest, err := http.NewRequest("DELETE",
r.imageManifestURL(name, tag), nil)
if err != nil {
return err
}
response, err := http.DefaultClient.Do(deleteRequest)
if err != nil {
return err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusNoContent:
break
case response.StatusCode == http.StatusNotFound:
return &ImageManifestNotFoundError{Name: name, Tag: tag}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return err
}
return &errs
default:
return &UnexpectedHTTPStatusError{Status: response.Status}
}
return nil
}
func (r *clientImpl) ListImageTags(name string) ([]string, error) {
response, err := http.Get(fmt.Sprintf("%s/v2/%s/tags/list", r.Endpoint, name))
if err != nil {
return nil, err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusOK:
break
case response.StatusCode == http.StatusNotFound:
return nil, &RepositoryNotFoundError{Name: name}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return nil, err
}
return nil, &errs
default:
return nil, &UnexpectedHTTPStatusError{Status: response.Status}
}
tags := struct {
Tags []string `json:"tags"`
}{}
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&tags)
if err != nil {
return nil, err
}
return tags.Tags, nil
}
func (r *clientImpl) BlobLength(name string, dgst digest.Digest) (int, error) {
response, err := http.Head(fmt.Sprintf("%s/v2/%s/blob/%s", r.Endpoint, name, dgst))
if err != nil {
return -1, err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusOK:
lengthHeader := response.Header.Get("Content-Length")
length, err := strconv.ParseInt(lengthHeader, 10, 64)
if err != nil {
return -1, err
}
return int(length), nil
case response.StatusCode == http.StatusNotFound:
return -1, nil
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return -1, err
}
return -1, &errs
default:
response.Body.Close()
return -1, &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) GetBlob(name string, dgst digest.Digest, byteOffset int) (io.ReadCloser, int, error) {
getRequest, err := http.NewRequest("GET",
fmt.Sprintf("%s/v2/%s/blob/%s", r.Endpoint, name, dgst), nil)
if err != nil {
return nil, 0, err
}
getRequest.Header.Add("Range", fmt.Sprintf("%d-", byteOffset))
response, err := http.DefaultClient.Do(getRequest)
if err != nil {
return nil, 0, err
}
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusOK:
lengthHeader := response.Header.Get("Content-Length")
length, err := strconv.ParseInt(lengthHeader, 10, 0)
if err != nil {
return nil, 0, err
}
return response.Body, int(length), nil
case response.StatusCode == http.StatusNotFound:
response.Body.Close()
return nil, 0, &BlobNotFoundError{Name: name, Digest: dgst}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return nil, 0, err
}
return nil, 0, &errs
default:
response.Body.Close()
return nil, 0, &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) InitiateBlobUpload(name string) (string, error) {
postRequest, err := http.NewRequest("POST",
fmt.Sprintf("%s/v2/%s/blob/upload/", r.Endpoint, name), nil)
if err != nil {
return "", err
}
response, err := http.DefaultClient.Do(postRequest)
if err != nil {
return "", err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusAccepted:
return response.Header.Get("Location"), nil
// case response.StatusCode == http.StatusNotFound:
// return
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return "", err
}
return "", &errs
default:
return "", &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) GetBlobUploadStatus(location string) (int, int, error) {
response, err := http.Get(location)
if err != nil {
return 0, 0, err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusNoContent:
return parseRangeHeader(response.Header.Get("Range"))
case response.StatusCode == http.StatusNotFound:
return 0, 0, &BlobUploadNotFoundError{Location: location}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return 0, 0, err
}
return 0, 0, &errs
default:
return 0, 0, &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) UploadBlob(location string, blob io.ReadCloser, length int, dgst digest.Digest) error {
defer blob.Close()
putRequest, err := http.NewRequest("PUT", location, blob)
if err != nil {
return err
}
queryValues := url.Values{}
queryValues.Set("size", fmt.Sprint(length))
queryValues.Set("digest", dgst.String())
putRequest.URL.RawQuery = queryValues.Encode()
putRequest.Header.Set("Content-Type", "application/octet-stream")
putRequest.Header.Set("Content-Length", fmt.Sprint(length))
response, err := http.DefaultClient.Do(putRequest)
if err != nil {
return err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusCreated:
return nil
case response.StatusCode == http.StatusNotFound:
return &BlobUploadNotFoundError{Location: location}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return err
}
return &errs
default:
return &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) UploadBlobChunk(location string, blobChunk io.ReadCloser, length, startByte int) error {
defer blobChunk.Close()
putRequest, err := http.NewRequest("PUT",
fmt.Sprintf("%s%s", r.Endpoint, location), blobChunk)
if err != nil {
return err
}
endByte := startByte + length
putRequest.Header.Set("Content-Type", "application/octet-stream")
putRequest.Header.Set("Content-Length", fmt.Sprint(length))
putRequest.Header.Set("Content-Range",
fmt.Sprintf("%d-%d/%d", startByte, endByte, endByte))
response, err := http.DefaultClient.Do(putRequest)
if err != nil {
return err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusAccepted:
return nil
case response.StatusCode == http.StatusRequestedRangeNotSatisfiable:
lastValidRange, blobSize, err := parseRangeHeader(response.Header.Get("Range"))
if err != nil {
return err
}
return &BlobUploadInvalidRangeError{
Location: location,
LastValidRange: lastValidRange,
BlobSize: blobSize,
}
case response.StatusCode == http.StatusNotFound:
return &BlobUploadNotFoundError{Location: location}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return err
}
return &errs
default:
return &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) FinishChunkedBlobUpload(location string, length int, dgst digest.Digest) error {
putRequest, err := http.NewRequest("PUT",
fmt.Sprintf("%s%s", r.Endpoint, location), nil)
if err != nil {
return err
}
queryValues := new(url.Values)
queryValues.Set("size", fmt.Sprint(length))
queryValues.Set("digest", dgst.String())
putRequest.URL.RawQuery = queryValues.Encode()
putRequest.Header.Set("Content-Type", "application/octet-stream")
putRequest.Header.Set("Content-Length", "0")
putRequest.Header.Set("Content-Range",
fmt.Sprintf("%d-%d/%d", length, length, length))
response, err := http.DefaultClient.Do(putRequest)
if err != nil {
return err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusCreated:
return nil
case response.StatusCode == http.StatusNotFound:
return &BlobUploadNotFoundError{Location: location}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return err
}
return &errs
default:
return &UnexpectedHTTPStatusError{Status: response.Status}
}
}
func (r *clientImpl) CancelBlobUpload(location string) error {
deleteRequest, err := http.NewRequest("DELETE",
fmt.Sprintf("%s%s", r.Endpoint, location), nil)
if err != nil {
return err
}
response, err := http.DefaultClient.Do(deleteRequest)
if err != nil {
return err
}
defer response.Body.Close()
// TODO(bbland): handle other status codes, like 5xx errors
switch {
case response.StatusCode == http.StatusNoContent:
return nil
case response.StatusCode == http.StatusNotFound:
return &BlobUploadNotFoundError{Location: location}
case response.StatusCode >= 400 && response.StatusCode < 500:
var errs errors.Errors
decoder := json.NewDecoder(response.Body)
err = decoder.Decode(&errs)
if err != nil {
return err
}
return &errs
default:
return &UnexpectedHTTPStatusError{Status: response.Status}
}
}
// imageManifestURL is a helper method for returning the full url to an image
// manifest
func (r *clientImpl) imageManifestURL(name, tag string) string {
return fmt.Sprintf("%s/v2/%s/manifest/%s", r.Endpoint, name, tag)
}
// parseRangeHeader parses out the offset and length from a returned Range
// header
func parseRangeHeader(byteRangeHeader string) (int, int, error) {
r := regexp.MustCompile("bytes=0-(\\d+)/(\\d+)")
submatches := r.FindStringSubmatch(byteRangeHeader)
offset, err := strconv.ParseInt(submatches[1], 10, 0)
if err != nil {
return 0, 0, err
}
length, err := strconv.ParseInt(submatches[2], 10, 0)
if err != nil {
return 0, 0, err
}
return int(offset), int(length), nil
}