Move client package under registry package

Signed-off-by: Stephen J Day <stephen.day@docker.com>

docs/client/client.go

@@ -0,0 +1,574 @@
+package client
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"regexp"
+	"strconv"
+
+	"github.com/docker/distribution/registry/api/v2"
+	"github.com/docker/distribution/digest"
+	"github.com/docker/distribution/manifest"
+)
+
+// 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) (*manifest.SignedManifest, error)
+
+	// PutImageManifest uploads an image manifest for the image at the given
+	// name, tag pair.
+	PutImageManifest(name, tag string, imageManifest *manifest.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
+}
+
+var (
+	patternRangeHeader = regexp.MustCompile("bytes=0-(\\d+)/(\\d+)")
+)
+
+// 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, error) {
+	ub, err := v2.NewURLBuilderFromString(endpoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return &clientImpl{
+		endpoint: endpoint,
+		ub:       ub,
+	}, nil
+}
+
+// clientImpl is the default implementation of the Client interface
+type clientImpl struct {
+	endpoint string
+	ub       *v2.URLBuilder
+}
+
+// TODO(bbland): use consistent route generation between server and client
+
+func (r *clientImpl) GetImageManifest(name, tag string) (*manifest.SignedManifest, error) {
+	manifestURL, err := r.ub.BuildManifestURL(name, tag)
+	if err != nil {
+		return nil, err
+	}
+
+	response, err := http.Get(manifestURL)
+	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 v2.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(manifest.SignedManifest)
+	err = decoder.Decode(manifest)
+	if err != nil {
+		return nil, err
+	}
+	return manifest, nil
+}
+
+func (r *clientImpl) PutImageManifest(name, tag string, manifest *manifest.SignedManifest) error {
+	manifestURL, err := r.ub.BuildManifestURL(name, tag)
+	if err != nil {
+		return err
+	}
+
+	putRequest, err := http.NewRequest("PUT", manifestURL, 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 || response.StatusCode == http.StatusAccepted:
+		return nil
+	case response.StatusCode >= 400 && response.StatusCode < 500:
+		var errors v2.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 {
+	manifestURL, err := r.ub.BuildManifestURL(name, tag)
+	if err != nil {
+		return err
+	}
+
+	deleteRequest, err := http.NewRequest("DELETE", manifestURL, 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 v2.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) {
+	tagsURL, err := r.ub.BuildTagsURL(name)
+	if err != nil {
+		return nil, err
+	}
+
+	response, err := http.Get(tagsURL)
+	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 v2.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) {
+	blobURL, err := r.ub.BuildBlobURL(name, dgst)
+	if err != nil {
+		return -1, err
+	}
+
+	response, err := http.Head(blobURL)
+	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 v2.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) {
+	blobURL, err := r.ub.BuildBlobURL(name, dgst)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	getRequest, err := http.NewRequest("GET", blobURL, 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 v2.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) {
+	uploadURL, err := r.ub.BuildBlobUploadURL(name)
+	if err != nil {
+		return "", err
+	}
+
+	postRequest, err := http.NewRequest("POST", uploadURL, 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 v2.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 v2.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
+	}
+
+	values := putRequest.URL.Query()
+	values.Set("digest", dgst.String())
+	putRequest.URL.RawQuery = values.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 v2.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", 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 v2.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", location, nil)
+	if err != nil {
+		return err
+	}
+
+	values := putRequest.URL.Query()
+	values.Set("digest", dgst.String())
+	putRequest.URL.RawQuery = values.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 v2.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", 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 v2.Errors
+		decoder := json.NewDecoder(response.Body)
+		err = decoder.Decode(&errs)
+		if err != nil {
+			return err
+		}
+		return &errs
+	default:
+		return &UnexpectedHTTPStatusError{Status: response.Status}
+	}
+}
+
+// parseRangeHeader parses out the offset and length from a returned Range
+// header
+func parseRangeHeader(byteRangeHeader string) (int, int, error) {
+	submatches := patternRangeHeader.FindStringSubmatch(byteRangeHeader)
+	if submatches == nil || len(submatches) < 3 {
+		return 0, 0, fmt.Errorf("Malformed Range header")
+	}
+
+	offset, err := strconv.Atoi(submatches[1])
+	if err != nil {
+		return 0, 0, err
+	}
+	length, err := strconv.Atoi(submatches[2])
+	if err != nil {
+		return 0, 0, err
+	}
+	return offset, length, nil
+}