commit 36b58e5abf2fc632a6481348ad52a9ecb055715c
Author: Guillaume J. Charmes <charmes.guillaume@gmail.com>
Date:   Wed May 15 01:41:39 2013 +0000

    Split registry into subpackage

diff --git a/docs/registry.go b/docs/registry.go
new file mode 100644
index 00000000..8900f275
--- /dev/null
+++ b/docs/registry.go
@@ -0,0 +1,659 @@
+package registry
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/dotcloud/docker/auth"
+	"github.com/dotcloud/docker/utils"
+	"github.com/shin-/cookiejar"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+func doWithCookies(c *http.Client, req *http.Request) (*http.Response, error) {
+	for _, cookie := range c.Jar.Cookies(req.URL) {
+		req.AddCookie(cookie)
+	}
+	return c.Do(req)
+}
+
+// Retrieve the history of a given image from the Registry.
+// Return a list of the parent's json (requested image included)
+func (r *Registry) GetRemoteHistory(imgId, registry string, token []string) ([]string, error) {
+	client := r.getHttpClient()
+
+	req, err := http.NewRequest("GET", registry+"/images/"+imgId+"/ancestry", nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Authorization", "Token "+strings.Join(token, ", "))
+	res, err := client.Do(req)
+	if err != nil || res.StatusCode != 200 {
+		if res != nil {
+			return nil, fmt.Errorf("Internal server error: %d trying to fetch remote history for %s", res.StatusCode, imgId)
+		}
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	jsonString, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, fmt.Errorf("Error while reading the http response: %s\n", err)
+	}
+
+	utils.Debugf("Ancestry: %s", jsonString)
+	history := new([]string)
+	if err := json.Unmarshal(jsonString, history); err != nil {
+		return nil, err
+	}
+	return *history, nil
+}
+
+func (r *Registry) getHttpClient() *http.Client {
+	if r.httpClient == nil {
+		r.httpClient = &http.Client{}
+		r.httpClient.Jar = cookiejar.NewCookieJar()
+	}
+	return r.httpClient
+}
+
+// Check if an image exists in the Registry
+func (r *Registry) LookupRemoteImage(imgId, registry string, authConfig *auth.AuthConfig) bool {
+	rt := &http.Transport{Proxy: http.ProxyFromEnvironment}
+
+	req, err := http.NewRequest("GET", registry+"/images/"+imgId+"/json", nil)
+	if err != nil {
+		return false
+	}
+	req.SetBasicAuth(authConfig.Username, authConfig.Password)
+	res, err := rt.RoundTrip(req)
+	return err == nil && res.StatusCode == 307
+}
+
+func (r *Registry) getImagesInRepository(repository string, authConfig *auth.AuthConfig) ([]map[string]string, error) {
+	u := auth.IndexServerAddress() + "/repositories/" + repository + "/images"
+	req, err := http.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, err
+	}
+	if authConfig != nil && len(authConfig.Username) > 0 {
+		req.SetBasicAuth(authConfig.Username, authConfig.Password)
+	}
+	res, err := r.getHttpClient().Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	// Repository doesn't exist yet
+	if res.StatusCode == 404 {
+		return nil, nil
+	}
+
+	jsonData, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	imageList := []map[string]string{}
+
+	err = json.Unmarshal(jsonData, &imageList)
+	if err != nil {
+		utils.Debugf("Body: %s (%s)\n", res.Body, u)
+		return nil, err
+	}
+
+	return imageList, nil
+}
+
+// Retrieve an image from the Registry.
+// Returns the Image object as well as the layer as an Archive (io.Reader)
+func (r *Registry) GetRemoteImageJson(stdout io.Writer, imgId, registry string, token []string) ([]byte, error) {
+	client := r.getHttpClient()
+
+	fmt.Fprintf(stdout, "Pulling %s metadata\r\n", imgId)
+	// Get the Json
+	req, err := http.NewRequest("GET", registry+"/images/"+imgId+"/json", nil)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to download json: %s", err)
+	}
+	req.Header.Set("Authorization", "Token "+strings.Join(token, ", "))
+	res, err := client.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to download json: %s", err)
+	}
+	defer res.Body.Close()
+	if res.StatusCode != 200 {
+		return nil, fmt.Errorf("HTTP code %d", res.StatusCode)
+	}
+	jsonString, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to parse downloaded json: %s (%s)", err, jsonString)
+	}
+	return jsonString, nil
+}
+
+func (r *Registry) GetRemoteImageLayer(stdout io.Writer, imgId, registry string, token []string) (io.Reader, error) {
+	client := r.getHttpClient()
+
+	req, err := http.NewRequest("GET", registry+"/images/"+imgId+"/layer", nil)
+	if err != nil {
+		return nil, fmt.Errorf("Error while getting from the server: %s\n", err)
+	}
+	req.Header.Set("Authorization", "Token "+strings.Join(token, ", "))
+	res, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	return utils.ProgressReader(res.Body, int(res.ContentLength), stdout, "Downloading %v/%v (%v)"), nil
+}
+
+func (r *Registry) GetRemoteTags(stdout io.Writer, registries []string, repository string, token []string) (map[string]string, error) {
+	client := r.getHttpClient()
+	if strings.Count(repository, "/") == 0 {
+		// This will be removed once the Registry supports auto-resolution on
+		// the "library" namespace
+		repository = "library/" + repository
+	}
+	for _, host := range registries {
+		endpoint := fmt.Sprintf("https://%s/v1/repositories/%s/tags", host, repository)
+		req, err := http.NewRequest("GET", endpoint, nil)
+		if err != nil {
+			return nil, err
+		}
+		req.Header.Set("Authorization", "Token "+strings.Join(token, ", "))
+		res, err := client.Do(req)
+		defer res.Body.Close()
+		utils.Debugf("Got status code %d from %s", res.StatusCode, endpoint)
+		if err != nil || (res.StatusCode != 200 && res.StatusCode != 404) {
+			continue
+		} else if res.StatusCode == 404 {
+			return nil, fmt.Errorf("Repository not found")
+		}
+
+		result := make(map[string]string)
+
+		rawJson, err := ioutil.ReadAll(res.Body)
+		if err != nil {
+			return nil, err
+		}
+		if err := json.Unmarshal(rawJson, &result); err != nil {
+			return nil, err
+		}
+		return result, nil
+	}
+	return nil, fmt.Errorf("Could not reach any registry endpoint")
+}
+
+func (r *Registry) getImageForTag(stdout io.Writer, tag, remote, registry string, token []string) (string, error) {
+	client := r.getHttpClient()
+
+	if !strings.Contains(remote, "/") {
+		remote = "library/" + remote
+	}
+
+	registryEndpoint := "https://" + registry + "/v1"
+	repositoryTarget := registryEndpoint + "/repositories/" + remote + "/tags/" + tag
+
+	req, err := http.NewRequest("GET", repositoryTarget, nil)
+	if err != nil {
+		return "", err
+	}
+	req.Header.Set("Authorization", "Token "+strings.Join(token, ", "))
+	res, err := client.Do(req)
+	if err != nil {
+		return "", fmt.Errorf("Error while retrieving repository info: %v", err)
+	}
+	defer res.Body.Close()
+	if res.StatusCode == 403 {
+		return "", fmt.Errorf("You aren't authorized to access this resource")
+	} else if res.StatusCode != 200 {
+		return "", fmt.Errorf("HTTP code: %d", res.StatusCode)
+	}
+
+	var imgId string
+	rawJson, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return "", err
+	}
+	if err = json.Unmarshal(rawJson, &imgId); err != nil {
+		return "", err
+	}
+	return imgId, nil
+}
+
+func (r *Registry) GetRepositoryData(remote string) (*RepositoryData, error) {
+	client := r.getHttpClient()
+
+	utils.Debugf("Pulling repository %s from %s\r\n", remote, auth.IndexServerAddress())
+	repositoryTarget := auth.IndexServerAddress() + "/repositories/" + remote + "/images"
+
+	req, err := http.NewRequest("GET", repositoryTarget, nil)
+	if err != nil {
+		return nil, err
+	}
+	if r.authConfig != nil && len(r.authConfig.Username) > 0 {
+		req.SetBasicAuth(r.authConfig.Username, r.authConfig.Password)
+	}
+	req.Header.Set("X-Docker-Token", "true")
+
+	res, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	if res.StatusCode == 401 {
+		return nil, fmt.Errorf("Please login first (HTTP code %d)", res.StatusCode)
+	}
+	// TODO: Right now we're ignoring checksums in the response body.
+	// In the future, we need to use them to check image validity.
+	if res.StatusCode != 200 {
+		return nil, fmt.Errorf("HTTP code: %d", res.StatusCode)
+	}
+
+	var tokens []string
+	if res.Header.Get("X-Docker-Token") != "" {
+		tokens = res.Header["X-Docker-Token"]
+	}
+
+	var endpoints []string
+	if res.Header.Get("X-Docker-Endpoints") != "" {
+		endpoints = res.Header["X-Docker-Endpoints"]
+	} else {
+		return nil, fmt.Errorf("Index response didn't contain any endpoints")
+	}
+
+	checksumsJson, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, err
+	}
+	remoteChecksums := []*ImgData{}
+	if err := json.Unmarshal(checksumsJson, &remoteChecksums); err != nil {
+		return nil, err
+	}
+
+	// Forge a better object from the retrieved data
+	imgsData := make(map[string]*ImgData)
+	for _, elem := range remoteChecksums {
+		imgsData[elem.Id] = elem
+	}
+
+	return &RepositoryData{
+		ImgList:   imgsData,
+		Endpoints: endpoints,
+		Tokens:    tokens,
+	}, nil
+}
+
+// // Push a local image to the registry
+// func (r *Registry) PushImage(stdout io.Writer, img *Image, registry string, token []string) error {
+// 	registry = "https://" + registry + "/v1"
+
+// 	client := graph.getHttpClient()
+// 	jsonRaw, err := ioutil.ReadFile(path.Join(graph.Root, img.Id, "json"))
+// 	if err != nil {
+// 		return fmt.Errorf("Error while retreiving the path for {%s}: %s", img.Id, err)
+// 	}
+
+// 	fmt.Fprintf(stdout, "Pushing %s metadata\r\n", img.Id)
+
+// 	// FIXME: try json with UTF8
+// 	jsonData := strings.NewReader(string(jsonRaw))
+// 	req, err := http.NewRequest("PUT", registry+"/images/"+img.Id+"/json", jsonData)
+// 	if err != nil {
+// 		return err
+// 	}
+// 	req.Header.Add("Content-type", "application/json")
+// 	req.Header.Set("Authorization", "Token "+strings.Join(token, ","))
+
+// 	checksum, err := img.Checksum()
+// 	if err != nil {
+// 		return fmt.Errorf("Error while retrieving checksum for %s: %v", img.Id, err)
+// 	}
+// 	req.Header.Set("X-Docker-Checksum", checksum)
+// 	utils.Debugf("Setting checksum for %s: %s", img.ShortId(), checksum)
+// 	res, err := doWithCookies(client, req)
+// 	if err != nil {
+// 		return fmt.Errorf("Failed to upload metadata: %s", err)
+// 	}
+// 	defer res.Body.Close()
+// 	if len(res.Cookies()) > 0 {
+// 		client.Jar.SetCookies(req.URL, res.Cookies())
+// 	}
+// 	if res.StatusCode != 200 {
+// 		errBody, err := ioutil.ReadAll(res.Body)
+// 		if err != nil {
+// 			return fmt.Errorf("HTTP code %d while uploading metadata and error when"+
+// 				" trying to parse response body: %v", res.StatusCode, err)
+// 		}
+// 		var jsonBody map[string]string
+// 		if err := json.Unmarshal(errBody, &jsonBody); err != nil {
+// 			errBody = []byte(err.Error())
+// 		} else if jsonBody["error"] == "Image already exists" {
+// 			fmt.Fprintf(stdout, "Image %v already uploaded ; skipping\n", img.Id)
+// 			return nil
+// 		}
+// 		return fmt.Errorf("HTTP code %d while uploading metadata: %s", res.StatusCode, errBody)
+// 	}
+
+// 	fmt.Fprintf(stdout, "Pushing %s fs layer\r\n", img.Id)
+// 	root, err := img.root()
+// 	if err != nil {
+// 		return err
+// 	}
+
+// 	var layerData *TempArchive
+// 	// If the archive exists, use it
+// 	file, err := os.Open(layerArchivePath(root))
+// 	if err != nil {
+// 		if os.IsNotExist(err) {
+// 			// If the archive does not exist, create one from the layer
+// 			layerData, err = graph.TempLayerArchive(img.Id, Xz, stdout)
+// 			if err != nil {
+// 				return fmt.Errorf("Failed to generate layer archive: %s", err)
+// 			}
+// 		} else {
+// 			return err
+// 		}
+// 	} else {
+// 		defer file.Close()
+// 		st, err := file.Stat()
+// 		if err != nil {
+// 			return err
+// 		}
+// 		layerData = &TempArchive{file, st.Size()}
+// 	}
+
+// 	req3, err := http.NewRequest("PUT", registry+"/images/"+img.Id+"/layer", utils.ProgressReader(layerData, int(layerData.Size), stdout, ""))
+// 	if err != nil {
+// 		return err
+// 	}
+
+// 	req3.ContentLength = -1
+// 	req3.TransferEncoding = []string{"chunked"}
+// 	req3.Header.Set("Authorization", "Token "+strings.Join(token, ","))
+// 	res3, err := doWithCookies(client, req3)
+// 	if err != nil {
+// 		return fmt.Errorf("Failed to upload layer: %s", err)
+// 	}
+// 	defer res3.Body.Close()
+
+// 	if res3.StatusCode != 200 {
+// 		errBody, err := ioutil.ReadAll(res3.Body)
+// 		if err != nil {
+// 			return fmt.Errorf("HTTP code %d while uploading metadata and error when"+
+// 				" trying to parse response body: %v", res.StatusCode, err)
+// 		}
+// 		return fmt.Errorf("Received HTTP code %d while uploading layer: %s", res3.StatusCode, errBody)
+// 	}
+// 	return nil
+// }
+
+// // push a tag on the registry.
+// // Remote has the format '<user>/<repo>
+// func (r *Registry) pushTag(remote, revision, tag, registry string, token []string) error {
+// 	// "jsonify" the string
+// 	revision = "\"" + revision + "\""
+// 	registry = "https://" + registry + "/v1"
+
+// 	utils.Debugf("Pushing tags for rev [%s] on {%s}\n", revision, registry+"/users/"+remote+"/"+tag)
+
+// 	client := graph.getHttpClient()
+// 	req, err := http.NewRequest("PUT", registry+"/repositories/"+remote+"/tags/"+tag, strings.NewReader(revision))
+// 	if err != nil {
+// 		return err
+// 	}
+// 	req.Header.Add("Content-type", "application/json")
+// 	req.Header.Set("Authorization", "Token "+strings.Join(token, ","))
+// 	req.ContentLength = int64(len(revision))
+// 	res, err := doWithCookies(client, req)
+// 	if err != nil {
+// 		return err
+// 	}
+// 	res.Body.Close()
+// 	if res.StatusCode != 200 && res.StatusCode != 201 {
+// 		return fmt.Errorf("Internal server error: %d trying to push tag %s on %s", res.StatusCode, tag, remote)
+// 	}
+// 	return nil
+// }
+
+// // FIXME: this should really be PushTag
+// func (r *Registry) pushPrimitive(stdout io.Writer, remote, tag, imgId, registry string, token []string) error {
+// 	// Check if the local impage exists
+// 	img, err := graph.Get(imgId)
+// 	if err != nil {
+// 		fmt.Fprintf(stdout, "Skipping tag %s:%s: %s does not exist\r\n", remote, tag, imgId)
+// 		return nil
+// 	}
+// 	fmt.Fprintf(stdout, "Pushing image %s:%s\r\n", remote, tag)
+// 	// Push the image
+// 	if err = graph.PushImage(stdout, img, registry, token); err != nil {
+// 		return err
+// 	}
+// 	fmt.Fprintf(stdout, "Registering tag %s:%s\r\n", remote, tag)
+// 	// And then the tag
+// 	if err = graph.pushTag(remote, imgId, tag, registry, token); err != nil {
+// 		return err
+// 	}
+// 	return nil
+// }
+
+// // Retrieve the checksum of an image
+// // Priority:
+// // - Check on the stored checksums
+// // - Check if the archive exists, if it does not, ask the registry
+// // - If the archive does exists, process the checksum from it
+// // - If the archive does not exists and not found on registry, process checksum from layer
+// func (r *Registry) getChecksum(imageId string) (string, error) {
+// 	// FIXME: Use in-memory map instead of reading the file each time
+// 	if sums, err := graph.getStoredChecksums(); err != nil {
+// 		return "", err
+// 	} else if checksum, exists := sums[imageId]; exists {
+// 		return checksum, nil
+// 	}
+
+// 	img, err := graph.Get(imageId)
+// 	if err != nil {
+// 		return "", err
+// 	}
+
+// 	if _, err := os.Stat(layerArchivePath(graph.imageRoot(imageId))); err != nil {
+// 		if os.IsNotExist(err) {
+// 			// TODO: Ask the registry for the checksum
+// 			//       As the archive is not there, it is supposed to come from a pull.
+// 		} else {
+// 			return "", err
+// 		}
+// 	}
+
+// 	checksum, err := img.Checksum()
+// 	if err != nil {
+// 		return "", err
+// 	}
+// 	return checksum, nil
+// }
+
+// // Push a repository to the registry.
+// // Remote has the format '<user>/<repo>
+// func (r *Registry) PushRepository(stdout io.Writer, remote string, localRepo Repository, authConfig *auth.AuthConfig) error {
+// 	client := graph.getHttpClient()
+// 	// FIXME: Do not reset the cookie each time? (need to reset it in case updating latest of a repo and repushing)
+// 	client.Jar = cookiejar.NewCookieJar()
+// 	var imgList []*ImgListJson
+
+// 	fmt.Fprintf(stdout, "Processing checksums\n")
+// 	imageSet := make(map[string]struct{})
+
+// 	for tag, id := range localRepo {
+// 		img, err := graph.Get(id)
+// 		if err != nil {
+// 			return err
+// 		}
+// 		img.WalkHistory(func(img *Image) error {
+// 			if _, exists := imageSet[img.Id]; exists {
+// 				return nil
+// 			}
+// 			imageSet[img.Id] = struct{}{}
+// 			checksum, err := graph.getChecksum(img.Id)
+// 			if err != nil {
+// 				return err
+// 			}
+// 			imgList = append([]*ImgListJson{{
+// 				Id:       img.Id,
+// 				Checksum: checksum,
+// 				tag:      tag,
+// 			}}, imgList...)
+// 			return nil
+// 		})
+// 	}
+
+// 	imgListJson, err := json.Marshal(imgList)
+// 	if err != nil {
+// 		return err
+// 	}
+
+// 	utils.Debugf("json sent: %s\n", imgListJson)
+
+// 	fmt.Fprintf(stdout, "Sending image list\n")
+// 	req, err := http.NewRequest("PUT", auth.IndexServerAddress()+"/repositories/"+remote+"/", bytes.NewReader(imgListJson))
+// 	if err != nil {
+// 		return err
+// 	}
+// 	req.SetBasicAuth(authConfig.Username, authConfig.Password)
+// 	req.ContentLength = int64(len(imgListJson))
+// 	req.Header.Set("X-Docker-Token", "true")
+
+// 	res, err := client.Do(req)
+// 	if err != nil {
+// 		return err
+// 	}
+// 	defer res.Body.Close()
+
+// 	for res.StatusCode >= 300 && res.StatusCode < 400 {
+// 		utils.Debugf("Redirected to %s\n", res.Header.Get("Location"))
+// 		req, err = http.NewRequest("PUT", res.Header.Get("Location"), bytes.NewReader(imgListJson))
+// 		if err != nil {
+// 			return err
+// 		}
+// 		req.SetBasicAuth(authConfig.Username, authConfig.Password)
+// 		req.ContentLength = int64(len(imgListJson))
+// 		req.Header.Set("X-Docker-Token", "true")
+
+// 		res, err = client.Do(req)
+// 		if err != nil {
+// 			return err
+// 		}
+// 		defer res.Body.Close()
+// 	}
+
+// 	if res.StatusCode != 200 && res.StatusCode != 201 {
+// 		errBody, err := ioutil.ReadAll(res.Body)
+// 		if err != nil {
+// 			return err
+// 		}
+// 		return fmt.Errorf("Error: Status %d trying to push repository %s: %s", res.StatusCode, remote, errBody)
+// 	}
+
+// 	var token, endpoints []string
+// 	if res.Header.Get("X-Docker-Token") != "" {
+// 		token = res.Header["X-Docker-Token"]
+// 		utils.Debugf("Auth token: %v", token)
+// 	} else {
+// 		return fmt.Errorf("Index response didn't contain an access token")
+// 	}
+// 	if res.Header.Get("X-Docker-Endpoints") != "" {
+// 		endpoints = res.Header["X-Docker-Endpoints"]
+// 	} else {
+// 		return fmt.Errorf("Index response didn't contain any endpoints")
+// 	}
+
+// 	// FIXME: Send only needed images
+// 	for _, registry := range endpoints {
+// 		fmt.Fprintf(stdout, "Pushing repository %s to %s (%d tags)\r\n", remote, registry, len(localRepo))
+// 		// For each image within the repo, push them
+// 		for _, elem := range imgList {
+// 			if err := graph.pushPrimitive(stdout, remote, elem.tag, elem.Id, registry, token); err != nil {
+// 				// FIXME: Continue on error?
+// 				return err
+// 			}
+// 		}
+// 	}
+
+// 	req2, err := http.NewRequest("PUT", auth.IndexServerAddress()+"/repositories/"+remote+"/images", bytes.NewReader(imgListJson))
+// 	if err != nil {
+// 		return err
+// 	}
+// 	req2.SetBasicAuth(authConfig.Username, authConfig.Password)
+// 	req2.Header["X-Docker-Endpoints"] = endpoints
+// 	req2.ContentLength = int64(len(imgListJson))
+// 	res2, err := client.Do(req2)
+// 	if err != nil {
+// 		return err
+// 	}
+// 	defer res2.Body.Close()
+// 	if res2.StatusCode != 204 {
+// 		if errBody, err := ioutil.ReadAll(res2.Body); err != nil {
+// 			return err
+// 		} else {
+// 			return fmt.Errorf("Error: Status %d trying to push checksums %s: %s", res2.StatusCode, remote, errBody)
+// 		}
+// 	}
+
+// 	return nil
+// }
+
+func (r *Registry) SearchRepositories(stdout io.Writer, term string) (*SearchResults, error) {
+	client := r.getHttpClient()
+	u := auth.IndexServerAddress() + "/search?q=" + url.QueryEscape(term)
+	req, err := http.NewRequest("GET", u, nil)
+	if err != nil {
+		return nil, err
+	}
+	res, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+	if res.StatusCode != 200 {
+		return nil, fmt.Errorf("Unexepected status code %d", res.StatusCode)
+	}
+	rawData, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return nil, err
+	}
+	result := new(SearchResults)
+	err = json.Unmarshal(rawData, result)
+	return result, err
+}
+
+type SearchResults struct {
+	Query      string              `json:"query"`
+	NumResults int                 `json:"num_results"`
+	Results    []map[string]string `json:"results"`
+}
+
+type RepositoryData struct {
+	ImgList   map[string]*ImgData
+	Endpoints []string
+	Tokens    []string
+}
+
+type ImgData struct {
+	Id       string `json:"id"`
+	Checksum string `json:"checksum,omitempty"`
+	Tag      string `json:",omitempty"`
+}
+
+type Registry struct {
+	httpClient *http.Client
+	authConfig *auth.AuthConfig
+}
+
+func NewRegistry(authConfig *auth.AuthConfig) *Registry {
+	return &Registry{
+		authConfig: authConfig,
+	}
+}
diff --git a/docs/registry_test.go b/docs/registry_test.go
new file mode 100644
index 00000000..cead591a
--- /dev/null
+++ b/docs/registry_test.go
@@ -0,0 +1,151 @@
+package registry
+
+import (
+	"crypto/rand"
+	"encoding/hex"
+	"github.com/dotcloud/docker/auth"
+	"io/ioutil"
+	"os"
+	"path"
+	"testing"
+)
+
+func TestPull(t *testing.T) {
+	os.Setenv("DOCKER_INDEX_URL", "")
+	runtime, err := newTestRuntime()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer nuke(runtime)
+
+	err = runtime.graph.PullRepository(ioutil.Discard, "busybox", "", runtime.repositories, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	img, err := runtime.repositories.LookupImage("busybox")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Try to run something on this image to make sure the layer's been downloaded properly.
+	config, _, err := ParseRun([]string{img.Id, "echo", "Hello World"}, runtime.capabilities)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	b := NewBuilder(runtime)
+	container, err := b.Create(config)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := container.Start(); err != nil {
+		t.Fatal(err)
+	}
+
+	if status := container.Wait(); status != 0 {
+		t.Fatalf("Expected status code 0, found %d instead", status)
+	}
+}
+
+func TestPullTag(t *testing.T) {
+	os.Setenv("DOCKER_INDEX_URL", "")
+	runtime, err := newTestRuntime()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer nuke(runtime)
+
+	err = runtime.graph.PullRepository(ioutil.Discard, "ubuntu", "12.04", runtime.repositories, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	_, err = runtime.repositories.LookupImage("ubuntu:12.04")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	img2, err := runtime.repositories.LookupImage("ubuntu:12.10")
+	if img2 != nil {
+		t.Fatalf("Expected nil image but found %v instead", img2.Id)
+	}
+}
+
+func login(runtime *Runtime) error {
+	authConfig := auth.NewAuthConfig("unittester", "surlautrerivejetattendrai", "noise+unittester@dotcloud.com", runtime.root)
+	runtime.authConfig = authConfig
+	_, err := auth.Login(authConfig)
+	return err
+}
+
+func TestPush(t *testing.T) {
+	os.Setenv("DOCKER_INDEX_URL", "https://indexstaging-docker.dotcloud.com")
+	defer os.Setenv("DOCKER_INDEX_URL", "")
+	runtime, err := newTestRuntime()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer nuke(runtime)
+
+	err = login(runtime)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = runtime.graph.PullRepository(ioutil.Discard, "joffrey/busybox", "", runtime.repositories, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	tokenBuffer := make([]byte, 16)
+	_, err = rand.Read(tokenBuffer)
+	if err != nil {
+		t.Fatal(err)
+	}
+	token := hex.EncodeToString(tokenBuffer)[:29]
+	config, _, err := ParseRun([]string{"joffrey/busybox", "touch", "/" + token}, runtime.capabilities)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	b := NewBuilder(runtime)
+	container, err := b.Create(config)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := container.Start(); err != nil {
+		t.Fatal(err)
+	}
+
+	if status := container.Wait(); status != 0 {
+		t.Fatalf("Expected status code 0, found %d instead", status)
+	}
+
+	img, err := b.Commit(container, "unittester/"+token, "", "", "", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	repo := runtime.repositories.Repositories["unittester/"+token]
+	err = runtime.graph.PushRepository(ioutil.Discard, "unittester/"+token, repo, runtime.authConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Remove image so we can pull it again
+	if err := runtime.graph.Delete(img.Id); err != nil {
+		t.Fatal(err)
+	}
+
+	err = runtime.graph.PullRepository(ioutil.Discard, "unittester/"+token, "", runtime.repositories, runtime.authConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	layerPath, err := img.layer()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := os.Stat(path.Join(layerPath, token)); err != nil {
+		t.Fatalf("Error while trying to retrieve token file: %v", err)
+	}
+}