From 06ebc514a70a1f8f1e63402373be395f008353be Mon Sep 17 00:00:00 2001 From: Stephen J Day Date: Thu, 18 Dec 2014 18:21:57 -0800 Subject: [PATCH] Automatically generate V2 API specification This changeset provides data structures and definitions describing the routes available in the V2 registry API. These route descriptors are structured to provide automated registration, for creating routers, in addition to complete documentation duty. It's also a possibility that this could be used to enumerate test coverage for server implementation. Using this functionality, we've also developed a template to automatically generate and API specification for submission into docker core. --- api/v2/descriptors.go | 855 ++++++++++++++++++- api/v2/errors_test.go | 2 +- api/v2/routes.go | 41 +- api/v2/routes_test.go | 8 +- cmd/registry-api-descriptor-template/main.go | 118 +++ cmd/registry-api-doctable-gen/main.go | 95 --- digest/digest.go | 6 + doc/SPEC.md.tmpl | 733 ++++++++++++++++ 8 files changed, 1717 insertions(+), 141 deletions(-) create mode 100644 cmd/registry-api-descriptor-template/main.go delete mode 100644 cmd/registry-api-doctable-gen/main.go create mode 100644 doc/SPEC.md.tmpl diff --git a/api/v2/descriptors.go b/api/v2/descriptors.go index 68d182411..f7b9de4b8 100644 --- a/api/v2/descriptors.go +++ b/api/v2/descriptors.go @@ -1,9 +1,246 @@ package v2 -import "net/http" +import ( + "net/http" + "regexp" -// TODO(stevvooe): Add route descriptors for each named route, along with -// accepted methods, parameters, returned status codes and error codes. + "github.com/docker/docker-registry/common" + "github.com/docker/docker-registry/digest" +) + +var ( + nameParameterDescriptor = ParameterDescriptor{ + Name: "name", + Type: "string", + Format: common.RepositoryNameRegexp.String(), + Required: true, + Description: `Name of the target repository.`, + } + + tagParameterDescriptor = ParameterDescriptor{ + Name: "tag", + Type: "string", + Format: common.TagNameRegexp.String(), + Required: true, + Description: `Tag of the target manifiest.`, + } + + uuidParameterDescriptor = ParameterDescriptor{ + Name: "uuid", + Type: "opaque", + Required: true, + Description: `A uuid identifying the upload. This field can accept almost anything.`, + } + + digestPathParameter = ParameterDescriptor{ + Name: "digest", + Type: "path", + Required: true, + Format: digest.DigestRegexp.String(), + Description: `Digest of desired blob.`, + } + + authHeader = ParameterDescriptor{ + Name: "Authorization", + Type: "string", + Description: "rfc7235 compliant authorization header.", + Format: " ", + Examples: []string{"Bearer dGhpcyBpcyBhIGZha2UgYmVhcmVyIHRva2VuIQ=="}, + } + + authChallengeHeader = ParameterDescriptor{ + Name: "WWW-Authenticate", + Type: "string", + Description: "An RFC7235 compliant authentication challenge header.", + Format: ` realm="", ..."`, + Examples: []string{ + `Bearer realm="https://auth.docker.com/", service="registry.docker.com", scopes="repository:library/ubuntu:pull"`, + }, + } + + contentLengthZeroHeader = ParameterDescriptor{ + Name: "Content-Length", + Description: "The `Content-Length` header must be zero and the body must be empty.", + Type: "integer", + Format: "0", + } +) + +const ( + manifestBody = `{ + "name": , + "tag": , + "fsLayers": [ + { + "blobSum": + }, + ... + ] + ], + "history": , + "signature": +}` + + errorsBody = `{ + "errors:" [{ + "code": , + "message": "", + "detail": ... + }, + ... + ] +}` +) + +// APIDescriptor exports descriptions of the layout of the v2 registry API. +var APIDescriptor = struct { + // RouteDescriptors provides a list of the routes available in the API. + RouteDescriptors []RouteDescriptor + + // ErrorDescriptors provides a list of the error codes and their + // associated documentation and metadata. + ErrorDescriptors []ErrorDescriptor +}{ + RouteDescriptors: routeDescriptors, + ErrorDescriptors: errorDescriptors, +} + +// RouteDescriptor describes a route specified by name. +type RouteDescriptor struct { + // Name is the name of the route, as specified in RouteNameXXX exports. + // These names a should be considered a unique reference for a route. If + // the route is registered with gorilla, this is the name that will be + // used. + Name string + + // Path is a gorilla/mux-compatible regexp that can be used to match the + // route. For any incoming method and path, only one route descriptor + // should match. + Path string + + // Entity should be a short, human-readalbe description of the object + // targeted by the endpoint. + Entity string + + // Description should provide an accurate overview of the functionality + // provided by the route. + Description string + + // Methods should describe the various HTTP methods that may be used on + // this route, including request and response formats. + Methods []MethodDescriptor +} + +// MethodDescriptor provides a description of the requests that may be +// conducted with the target method. +type MethodDescriptor struct { + + // Method is an HTTP method, such as GET, PUT or POST. + Method string + + // Description should provide an overview of the functionality provided by + // the covered method, suitable for use in documentation. Use of markdown + // here is encouraged. + Description string + + // Requests is a slice of request descriptors enumerating how this + // endpoint may be used. + Requests []RequestDescriptor +} + +// RequestDescriptor covers a particular set of headers and parameters that +// can be carried out with the parent method. Its most helpful to have one +// RequestDescriptor per API use case. +type RequestDescriptor struct { + // Name provides a short identifier for the request, usable as a title or + // to provide quick context for the particalar request. + Name string + + // Description should cover the requests purpose, covering any details for + // this particular use case. + Description string + + // Headers describes headers that must be used with the HTTP request. + Headers []ParameterDescriptor + + // PathParameters enumerate the parameterized path components for the + // given request, as defined in the route's regular expression. + PathParameters []ParameterDescriptor + + // QueryParameters provides a list of query parameters for the given + // request. + QueryParameters []ParameterDescriptor + + // Body describes the format of the request body. + Body BodyDescriptor + + // Successes enumerates the possible responses that are considered to be + // the result of a successful request. + Successes []ResponseDescriptor + + // Failures covers the possible failures from this particular request. + Failures []ResponseDescriptor +} + +// ResponseDescriptor describes the components of an API response. +type ResponseDescriptor struct { + // Name provides a short identifier for the response, usable as a title or + // to provide quick context for the particalar response. + Name string + + // Description should provide a brief overview of the role of the + // response. + Description string + + // StatusCode specifies the status recieved by this particular response. + StatusCode int + + // Headers covers any headers that may be returned from the response. + Headers []ParameterDescriptor + + // ErrorCodes enumerates the error codes that may be returned along with + // the response. + ErrorCodes []ErrorCode + + // Body describes the body of the response, if any. + Body BodyDescriptor +} + +// BodyDescriptor describes a request body and its expected content type. For +// the most part, it should be example json or some placeholder for body +// data in documentation. +type BodyDescriptor struct { + ContentType string + Format string +} + +// ParameterDescriptor describes the format of a request parameter, which may +// be a header, path parameter or query parameter. +type ParameterDescriptor struct { + // Name is the name of the parameter, either of the path component or + // query parameter. + Name string + + // Type specifies the type of the parameter, such as string, integer, etc. + Type string + + // Description provides a human-readable description of the parameter. + Description string + + // Required means the field is required when set. + Required bool + + // Format is a specifying the string format accepted by this parameter. + Format string + + // Regexp is a compiled regular expression that can be used to validate + // the contents of the parameter. + Regexp *regexp.Regexp + + // Examples provides multiple examples for the values that might be valid + // for this parameter. + Examples []string +} // ErrorDescriptor provides relevant information about a given error code. type ErrorDescriptor struct { @@ -29,9 +266,613 @@ type ErrorDescriptor struct { HTTPStatusCodes []int } +var routeDescriptors = []RouteDescriptor{ + { + Name: RouteNameBase, + Path: "/v2/", + Entity: "Base", + Description: `Base V2 API route. Typically, this can be used for lightweight version checks and to validate registry authorization.`, + Methods: []MethodDescriptor{ + { + Method: "GET", + Description: "Check that the endpoint implements Docker Registry API V2.", + Requests: []RequestDescriptor{ + { + Headers: []ParameterDescriptor{ + authHeader, + }, + Successes: []ResponseDescriptor{ + { + Description: "The API implements V2 protocol and is accessible.", + StatusCode: http.StatusOK, + }, + }, + Failures: []ResponseDescriptor{ + { + Description: "The client is not authorized to access the registry.", + StatusCode: http.StatusUnauthorized, + Headers: []ParameterDescriptor{ + authChallengeHeader, + }, + }, + { + Description: "The registry does not implement the V2 API.", + StatusCode: http.StatusNotFound, + }, + }, + }, + }, + }, + }, + }, + { + Name: RouteNameTags, + Path: "/v2/{name:" + common.RepositoryNameRegexp.String() + "}/tags/list", + Entity: "Tags", + Description: "Retrieve information about tags.", + Methods: []MethodDescriptor{ + { + Method: "GET", + Description: "Fetch the tags under the repository identified by `name`.", + Requests: []RequestDescriptor{ + { + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusOK, + Description: "A list of tags for the named repository.", + Body: BodyDescriptor{ + ContentType: "application/json", + Format: `{ + "name": , + "tags": [ + , + ... + ] +}`, + }, + }, + }, + Failures: []ResponseDescriptor{ + { + StatusCode: http.StatusNotFound, + Description: "The repository is not known to the registry.", + }, + { + StatusCode: http.StatusUnauthorized, + Description: "The client doesn't have access to repository.", + }, + }, + }, + }, + }, + }, + }, + { + Name: RouteNameManifest, + Path: "/v2/{name:" + common.RepositoryNameRegexp.String() + "}/manifests/{tag:" + common.TagNameRegexp.String() + "}", + Entity: "Manifest", + Description: "Create, update and retrieve manifests.", + Methods: []MethodDescriptor{ + { + Method: "GET", + Description: "Fetch the manifest identified by `name` and `tag`.", + Requests: []RequestDescriptor{ + { + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + tagParameterDescriptor, + }, + Successes: []ResponseDescriptor{ + { + Description: "The manifest idenfied by `name` and `tag`.", + StatusCode: http.StatusOK, + Body: BodyDescriptor{ + ContentType: "application/json", + Format: manifestBody, + }, + }, + }, + Failures: []ResponseDescriptor{ + { + Description: "The name or tag was invalid.", + StatusCode: http.StatusBadRequest, + ErrorCodes: []ErrorCode{ + ErrorCodeNameInvalid, + ErrorCodeTagInvalid, + }, + Body: BodyDescriptor{ + ContentType: "application/json", + Format: errorsBody, + }, + }, + { + Description: "The named manifest is not known to the registry.", + StatusCode: http.StatusNotFound, + ErrorCodes: []ErrorCode{ + ErrorCodeNameUnknown, + ErrorCodeManifestUnknown, + }, + Body: BodyDescriptor{ + ContentType: "application/json", + Format: errorsBody, + }, + }, + }, + }, + }, + }, + { + Method: "PUT", + Description: "Put the manifest identified by `name` and `tag`.", + Requests: []RequestDescriptor{ + { + Headers: []ParameterDescriptor{ + authHeader, + }, + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + tagParameterDescriptor, + }, + Body: BodyDescriptor{ + ContentType: "application/json", + Format: manifestBody, + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusAccepted, + }, + }, + Failures: []ResponseDescriptor{ + { + StatusCode: http.StatusBadRequest, + ErrorCodes: []ErrorCode{ + ErrorCodeNameInvalid, + ErrorCodeTagInvalid, + ErrorCodeManifestInvalid, + ErrorCodeManifestUnverified, + ErrorCodeBlobUnknown, + }, + }, + { + Description: "One or more layers may be missing during a manifest upload. If so, the missing layers will be enumerated in the error response.", + StatusCode: http.StatusBadRequest, + ErrorCodes: []ErrorCode{ + ErrorCodeBlobUnknown, + }, + Body: BodyDescriptor{ + ContentType: "application/json", + Format: `{ + "errors:" [{ + "code": "BLOB_UNKNOWN", + "message": "blob unknown to registry", + "detail": { + "digest": + } + }, + ... + ] +}`, + }, + }, + { + StatusCode: http.StatusUnauthorized, + Headers: []ParameterDescriptor{ + authChallengeHeader, + }, + }, + }, + }, + }, + }, + { + Method: "DELETE", + Description: "Delete the manifest identified by `name` and `tag`.", + Requests: []RequestDescriptor{ + { + Headers: []ParameterDescriptor{ + authHeader, + }, + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + tagParameterDescriptor, + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusAccepted, + }, + }, + Failures: []ResponseDescriptor{ + { + StatusCode: http.StatusBadRequest, + ErrorCodes: []ErrorCode{ + ErrorCodeNameInvalid, + ErrorCodeTagInvalid, + }, + }, + { + StatusCode: http.StatusUnauthorized, + Headers: []ParameterDescriptor{ + authChallengeHeader, + }, + }, + { + StatusCode: http.StatusNotFound, + ErrorCodes: []ErrorCode{ + ErrorCodeNameUnknown, + ErrorCodeManifestUnknown, + }, + }, + }, + }, + }, + }, + }, + }, + + { + Name: RouteNameBlob, + Path: "/v2/{name:" + common.RepositoryNameRegexp.String() + "}/blobs/{digest:" + digest.DigestRegexp.String() + "}", + Entity: "Blob", + Description: "Fetch the blob identified by `name` and `digest`. Used to fetch layers by tarsum digest.", + Methods: []MethodDescriptor{ + + { + Method: "GET", + Description: "Retrieve the blob from the registry identified by `digest`.", + Requests: []RequestDescriptor{ + { + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + digestPathParameter, + }, + Successes: []ResponseDescriptor{ + { + Description: "The blob identified by `digest` is available. The blob content will be present in the body of the request.", + StatusCode: http.StatusOK, + Body: BodyDescriptor{ + ContentType: "application/octet-stream", + Format: "", + }, + }, + { + Description: "The blob identified by `digest` is available at the provided location.", + StatusCode: http.StatusTemporaryRedirect, + Headers: []ParameterDescriptor{ + { + Name: "Location", + Type: "url", + Description: "The location where the layer should be accessible.", + Format: "", + }, + }, + }, + }, + Failures: []ResponseDescriptor{ + { + StatusCode: http.StatusBadRequest, + ErrorCodes: []ErrorCode{ + ErrorCodeNameInvalid, + ErrorCodeDigestInvalid, + }, + }, + { + StatusCode: http.StatusUnauthorized, + }, + { + StatusCode: http.StatusNotFound, + ErrorCodes: []ErrorCode{ + ErrorCodeNameUnknown, + ErrorCodeBlobUnknown, + }, + }, + }, + }, + }, + }, + { + Method: "HEAD", + Description: "Check if the blob is known to the registry.", + Requests: []RequestDescriptor{ + { + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + digestPathParameter, + }, + }, + }, + }, + // TODO(stevvooe): We may want to add a PUT request here to + // kickoff an upload of a blob, integrated with the blob upload + // API. + }, + }, + + { + Name: RouteNameBlobUpload, + Path: "/v2/{name:" + common.RepositoryNameRegexp.String() + "}/blobs/uploads/", + Entity: "Intiate Blob Upload", + Description: "Initiate a blob upload. This endpoint can be used to create resumable uploads or monolithic uploads.", + Methods: []MethodDescriptor{ + { + Method: "POST", + Description: "Initiate a resumable blob upload. If successful, an upload location will be provided to complete the upload. Optionally, if the `digest` parameter is present, the request body will be used to complete the upload in a single request.", + Requests: []RequestDescriptor{ + { + Name: "Initiate Monolithic Blob Upload", + Description: "Upload a blob identified by the `digest` parameter in single request. This upload will not be resumable unless a recoverable error is returned.", + Headers: []ParameterDescriptor{ + authHeader, + { + Name: "Content-Length", + Type: "integer", + Format: "", + }, + }, + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + }, + QueryParameters: []ParameterDescriptor{ + ParameterDescriptor{ + Name: "digest", + Type: "query", + Format: "", + Regexp: digest.DigestRegexp, + Description: `Digest of uploaded blob. If present, the upload will be completed, in a single request, with contents of the request body as the resulting blob.`, + }, + }, + Body: BodyDescriptor{ + ContentType: "application/octect-stream", + Format: "", + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusCreated, + Headers: []ParameterDescriptor{ + { + Name: "Location", + Type: "url", + Format: "", + }, + contentLengthZeroHeader, + }, + }, + }, + Failures: []ResponseDescriptor{ + { + Name: "Invalid Name or Digest", + StatusCode: http.StatusBadRequest, + ErrorCodes: []ErrorCode{ + ErrorCodeDigestInvalid, + ErrorCodeNameInvalid, + }, + }, + { + Name: "Unauthorized", + StatusCode: http.StatusUnauthorized, + Headers: []ParameterDescriptor{ + authChallengeHeader, + }, + ErrorCodes: []ErrorCode{ + ErrorCodeDigestInvalid, + ErrorCodeNameInvalid, + }, + }, + }, + }, + { + Name: "Initiate Resumable Blob Upload", + Description: "Initiate a resumable blob upload with an empty request body.", + Headers: []ParameterDescriptor{ + authHeader, + contentLengthZeroHeader, + }, + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + }, + Successes: []ResponseDescriptor{ + { + Description: "The upload has been created. The `Location` header must be used to complete the upload. The response should identical to a `GET` request on the contents of the returned `Location` header.", + StatusCode: http.StatusAccepted, + Headers: []ParameterDescriptor{ + contentLengthZeroHeader, + { + Name: "Location", + Type: "url", + Format: "/v2//blobs/uploads/", + Description: "The location of the created upload. Clients should use the contents verbatim to complete the upload, adding parameters where required.", + }, + { + Name: "Range", + Format: "0-0", + Description: "Range header indicating the progress of the upload. When starting an upload, it will return an empty range, since no content has been received.", + }, + }, + }, + }, + }, + }, + }, + }, + }, + + { + Name: RouteNameBlobUploadChunk, + Path: "/v2/{name:" + common.RepositoryNameRegexp.String() + "}/blobs/uploads/{uuid}", + Entity: "Blob Upload", + Description: "Interact with blob uploads. Clients should never assemble URLs for this endpoint and should only take it through the `Location` header on related API requests.", + Methods: []MethodDescriptor{ + { + Method: "GET", + Description: "Retrieve status of upload identified by `uuid`. The primary purpose of this endpoint is to resolve the current status of a resumable upload.", + Requests: []RequestDescriptor{ + { + Description: "Retrieve the progress of the current upload, as reported by the `Range` header.", + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + uuidParameterDescriptor, + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusNoContent, + Headers: []ParameterDescriptor{ + { + Name: "Range", + Type: "header", + Format: "0-", + Description: "Range indicating the current progress of the upload.", + }, + }, + }, + }, + }, + }, + }, + { + Method: "HEAD", + Description: "Retrieve status of upload identified by `uuid`. This is identical to the GET request.", + Requests: []RequestDescriptor{ + { + Description: "Retrieve the progress of the current upload, as reported by the `Range` header.", + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + uuidParameterDescriptor, + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusNoContent, + Headers: []ParameterDescriptor{ + { + Name: "Range", + Type: "header", + Format: "0-", + Description: "Range indicating the current progress of the upload.", + }, + }, + }, + }, + }, + }, + }, + { + Method: "PATCH", + Description: "Upload a chunk of data for the specified upload.", + Requests: []RequestDescriptor{ + { + Description: "Upload a chunk of data to specified upload without completing the upload.", + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + uuidParameterDescriptor, + }, + Headers: []ParameterDescriptor{ + { + Name: "Content-Range", + Type: "header", + Format: "-", + Required: true, + Description: "Range of bytes identifying the desired block of content represented by the body. Start must the end offset retrieved via status check plus one. Note that this is a non-standard use of the `Content-Range` header.", + }, + { + Name: "Content-Length", + Type: "integer", + Format: "", + Description: "Length of the chunk being uploaded, corresponding the length of the request body.", + }, + }, + Body: BodyDescriptor{ + ContentType: "application/octet-stream", + Format: "", + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusNoContent, + Headers: []ParameterDescriptor{ + { + Name: "Range", + Type: "header", + Format: "0-", + Description: "Range indicating the current progress of the upload.", + }, + contentLengthZeroHeader, + }, + }, + }, + }, + }, + }, + { + Method: "PUT", + Description: "Complete the upload specified by `uuid`, optionally appending the body as the final chunk.", + Requests: []RequestDescriptor{ + { + // TODO(stevvooe): Break this down into three separate requests: + // 1. Complete an upload where all data has already been sent. + // 2. Complete an upload where the entire body is in the PUT. + // 3. Complete an upload where the final, partial chunk is the body. + + Description: "Upload the _final_ chunk of data.", + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + uuidParameterDescriptor, + }, + QueryParameters: []ParameterDescriptor{ + ParameterDescriptor{ + Name: "digest", + Type: "string", + Format: "", + Regexp: digest.DigestRegexp, + Required: true, + Description: `Digest of uploaded blob.`, + }, + }, + Successes: []ResponseDescriptor{ + { + StatusCode: http.StatusNoContent, + Headers: []ParameterDescriptor{ + { + Name: "Content-Range", + Type: "header", + Format: "-", + Description: "Range of bytes identifying the desired block of content represented by the body. Start must match the end of offset retrieved via status check. Note that this is a non-standard use of the `Content-Range` header.", + }, + { + Name: "Content-Length", + Type: "integer", + Format: "", + Description: "Length of the chunk being uploaded, corresponding the length of the request body.", + }, + }, + Body: BodyDescriptor{ + ContentType: "application/octet-stream", + Format: "", + }, + }, + }, + }, + }, + }, + { + Method: "DELETE", + Description: "Cancel outstanding upload processes, releasing associated resources. If this is not called, the unfinished uploads will eventually timeout.", + Requests: []RequestDescriptor{ + { + Description: "Cancel the upload specified by `uuid`.", + PathParameters: []ParameterDescriptor{ + nameParameterDescriptor, + uuidParameterDescriptor, + }, + }, + }, + }, + }, + }, +} + // ErrorDescriptors provides a list of HTTP API Error codes that may be // encountered when interacting with the registry API. -var ErrorDescriptors = []ErrorDescriptor{ +var errorDescriptors = []ErrorDescriptor{ { Code: ErrorCodeUnknown, Value: "UNKNOWN", @@ -134,10 +975,10 @@ var errorCodeToDescriptors map[ErrorCode]ErrorDescriptor var idToDescriptors map[string]ErrorDescriptor func init() { - errorCodeToDescriptors = make(map[ErrorCode]ErrorDescriptor, len(ErrorDescriptors)) - idToDescriptors = make(map[string]ErrorDescriptor, len(ErrorDescriptors)) + errorCodeToDescriptors = make(map[ErrorCode]ErrorDescriptor, len(errorDescriptors)) + idToDescriptors = make(map[string]ErrorDescriptor, len(errorDescriptors)) - for _, descriptor := range ErrorDescriptors { + for _, descriptor := range errorDescriptors { errorCodeToDescriptors[descriptor.Code] = descriptor idToDescriptors[descriptor.Value] = descriptor } diff --git a/api/v2/errors_test.go b/api/v2/errors_test.go index d2fc091ac..70f3c2a95 100644 --- a/api/v2/errors_test.go +++ b/api/v2/errors_test.go @@ -11,7 +11,7 @@ import ( // TestErrorCodes ensures that error code format, mappings and // marshaling/unmarshaling. round trips are stable. func TestErrorCodes(t *testing.T) { - for _, desc := range ErrorDescriptors { + for _, desc := range errorDescriptors { if desc.Code.String() != desc.Value { t.Fatalf("error code string incorrect: %q != %q", desc.Code.String(), desc.Value) } diff --git a/api/v2/routes.go b/api/v2/routes.go index 7ebe61d66..ef9336009 100644 --- a/api/v2/routes.go +++ b/api/v2/routes.go @@ -1,9 +1,6 @@ package v2 -import ( - "github.com/docker/docker-registry/common" - "github.com/gorilla/mux" -) +import "github.com/gorilla/mux" // The following are definitions of the name under which all V2 routes are // registered. These symbols can be used to look up a route based on the name. @@ -31,39 +28,9 @@ func Router() *mux.Router { router := mux.NewRouter(). StrictSlash(true) - // GET /v2/ Check Check that the registry implements API version 2(.1) - router. - Path("/v2/"). - Name(RouteNameBase) - - // GET /v2//manifest/ Image Manifest Fetch the image manifest identified by name and tag. - // PUT /v2//manifest/ Image Manifest Upload the image manifest identified by name and tag. - // DELETE /v2//manifest/ Image Manifest Delete the image identified by name and tag. - router. - Path("/v2/{name:" + common.RepositoryNameRegexp.String() + "}/manifests/{tag:" + common.TagNameRegexp.String() + "}"). - Name(RouteNameManifest) - - // GET /v2//tags/list Tags Fetch the tags under the repository identified by name. - router. - Path("/v2/{name:" + common.RepositoryNameRegexp.String() + "}/tags/list"). - Name(RouteNameTags) - - // GET /v2//blob/ Layer Fetch the blob identified by digest. - router. - Path("/v2/{name:" + common.RepositoryNameRegexp.String() + "}/blobs/{digest:[a-zA-Z0-9-_+.]+:[a-zA-Z0-9-_+.=]+}"). - Name(RouteNameBlob) - - // POST /v2//blob/upload/ Layer Upload Initiate an upload of the layer identified by tarsum. - router. - Path("/v2/{name:" + common.RepositoryNameRegexp.String() + "}/blobs/uploads/"). - Name(RouteNameBlobUpload) - - // GET /v2//blob/upload/ Layer Upload Get the status of the upload identified by tarsum and uuid. - // PUT /v2//blob/upload/ Layer Upload Upload all or a chunk of the upload identified by tarsum and uuid. - // DELETE /v2//blob/upload/ Layer Upload Cancel the upload identified by layer and uuid - router. - Path("/v2/{name:" + common.RepositoryNameRegexp.String() + "}/blobs/uploads/{uuid}"). - Name(RouteNameBlobUploadChunk) + for _, descriptor := range routeDescriptors { + router.Path(descriptor.Path).Name(descriptor.Name) + } return router } diff --git a/api/v2/routes_test.go b/api/v2/routes_test.go index 9969ebcc4..29cd81064 100644 --- a/api/v2/routes_test.go +++ b/api/v2/routes_test.go @@ -140,7 +140,13 @@ func TestRouter(t *testing.T) { }, } { // Register the endpoint - router.GetRoute(testcase.RouteName).Handler(testHandler) + route := router.GetRoute(testcase.RouteName) + if route == nil { + t.Fatalf("route for name %q not found", testcase.RouteName) + } + + route.Handler(testHandler) + u := server.URL + testcase.RequestURI resp, err := http.Get(u) diff --git a/cmd/registry-api-descriptor-template/main.go b/cmd/registry-api-descriptor-template/main.go new file mode 100644 index 000000000..07b955a2e --- /dev/null +++ b/cmd/registry-api-descriptor-template/main.go @@ -0,0 +1,118 @@ +// registry-api-descriptor-template uses the APIDescriptor defined in the +// api/v2 package to execute templates passed to the command line. +// +// For example, to generate a new API specification, one would execute the +// following command from the repo root: +// +// $ registry-api-descriptor-template doc/SPEC.md.tmpl > doc/SPEC.md +// +// The templates are passed in the api/v2.APIDescriptor object. Please see the +// package documentation for fields available on that object. The template +// syntax is from Go's standard library text/template package. For information +// on Go's template syntax, please see golang.org/pkg/text/template. +package main + +import ( + "log" + "net/http" + "os" + "path/filepath" + "regexp" + "text/template" + + "github.com/docker/docker-registry/api/v2" +) + +var spaceRegex = regexp.MustCompile(`\n\s*`) + +func main() { + + if len(os.Args) != 2 { + log.Fatalln("please specify a template to execute.") + } + + path := os.Args[1] + filename := filepath.Base(path) + + funcMap := template.FuncMap{ + "removenewlines": func(s string) string { + return spaceRegex.ReplaceAllString(s, " ") + }, + "statustext": http.StatusText, + "prettygorilla": prettyGorillaMuxPath, + } + + tmpl := template.Must(template.New(filename).Funcs(funcMap).ParseFiles(path)) + + if err := tmpl.Execute(os.Stdout, v2.APIDescriptor); err != nil { + log.Fatalln(err) + } +} + +// prettyGorillaMuxPath removes the regular expressions from a gorilla/mux +// route string, making it suitable for documentation. +func prettyGorillaMuxPath(s string) string { + // Stateful parser that removes regular expressions from gorilla + // routes. It correctly handles balanced bracket pairs. + + var output string + var label string + var level int + +start: + if s[0] == '{' { + s = s[1:] + level++ + goto capture + } + + output += string(s[0]) + s = s[1:] + + goto end +capture: + switch s[0] { + case '{': + level++ + case '}': + level-- + + if level == 0 { + s = s[1:] + goto label + } + case ':': + s = s[1:] + goto skip + default: + label += string(s[0]) + } + s = s[1:] + goto capture +skip: + switch s[0] { + case '{': + level++ + case '}': + level-- + } + s = s[1:] + + if level == 0 { + goto label + } + + goto skip +label: + if label != "" { + output += "<" + label + ">" + label = "" + } +end: + if s != "" { + goto start + } + + return output + +} diff --git a/cmd/registry-api-doctable-gen/main.go b/cmd/registry-api-doctable-gen/main.go deleted file mode 100644 index a9e71ffff..000000000 --- a/cmd/registry-api-doctable-gen/main.go +++ /dev/null @@ -1,95 +0,0 @@ -// registry-api-doctable-gen uses various descriptors within the registry code -// base to generate markdown tables for use in documentation. This is only -// meant to facilitate updates to documentation and not as an automated tool. -// -// For now, this only includes support for error codes: -// -// $ registry-api-doctable-gen errors -// -package main - -import ( - "fmt" - "io" - "log" - "os" - "reflect" - "strings" - "text/tabwriter" - - "github.com/docker/docker-registry/api/v2" -) - -func main() { - - if len(os.Args) < 2 { - log.Fatalln("please specify a table to generate: (errors)") - } - - switch os.Args[1] { - case "errors": - dumpErrors(os.Stdout) - default: - log.Fatalln("unknown descriptor table:", os.Args[1]) - } - -} - -func dumpErrors(wr io.Writer) { - writer := tabwriter.NewWriter(os.Stdout, 8, 8, 0, '\t', 0) - defer writer.Flush() - - fmt.Fprint(writer, "|") - dtype := reflect.TypeOf(v2.ErrorDescriptor{}) - var fieldsPrinted int - for i := 0; i < dtype.NumField(); i++ { - field := dtype.Field(i) - if field.Name == "Value" { - continue - } - - fmt.Fprint(writer, field.Name, "|") - fieldsPrinted++ - } - - divider := strings.Repeat("-", 8) - var parts []string - for i := 0; i < fieldsPrinted; i++ { - parts = append(parts, divider) - } - divider = strings.Join(parts, "|") - - fmt.Fprintln(writer, "\n"+divider) - - for _, descriptor := range v2.ErrorDescriptors { - fmt.Fprint(writer, "|") - - v := reflect.ValueOf(descriptor) - for i := 0; i < dtype.NumField(); i++ { - value := v.Field(i).Interface() - field := v.Type().Field(i) - if field.Name == "Value" { - continue - } else if field.Name == "Description" { - value = strings.Replace(value.(string), "\n", " ", -1) - } else if field.Name == "Code" { - value = fmt.Sprintf("`%s`", value) - } else if field.Name == "HTTPStatusCodes" { - if len(value.([]int)) > 0 { - var codes []string - for _, code := range value.([]int) { - codes = append(codes, fmt.Sprint(code)) - } - value = strings.Join(codes, ", ") - } else { - value = "Any" - } - - } - - fmt.Fprint(writer, value, "|") - } - - fmt.Fprint(writer, "\n") - } -} diff --git a/digest/digest.go b/digest/digest.go index 6a3fdfd55..08abba5ca 100644 --- a/digest/digest.go +++ b/digest/digest.go @@ -7,6 +7,7 @@ import ( "hash" "io" "io/ioutil" + "regexp" "strings" "github.com/docker/docker-registry/common" @@ -36,6 +37,9 @@ func NewDigest(alg string, h hash.Hash) Digest { return Digest(fmt.Sprintf("%s:%x", alg, h.Sum(nil))) } +// DigestRegexp matches valid digest types. +var DigestRegexp = regexp.MustCompile(`[a-zA-Z0-9-_+.]+:[a-zA-Z0-9-_+.=]+`) + var ( // ErrDigestInvalidFormat returned when digest format invalid. ErrDigestInvalidFormat = fmt.Errorf("invalid checksum digest format") @@ -125,6 +129,8 @@ func (d Digest) Validate() error { return ErrDigestUnsupported } + // TODO(stevvooe): Use DigestRegexp to validate digest here. + return nil } diff --git a/doc/SPEC.md.tmpl b/doc/SPEC.md.tmpl new file mode 100644 index 000000000..cf2fbb2cf --- /dev/null +++ b/doc/SPEC.md.tmpl @@ -0,0 +1,733 @@ +# Docker Registry API V2.1 + +> **Note**: This specification has been ported over from the proposal on +> docker/docker#9015. Much of the language in this document is still written +> in the proposal tense and needs to be converted. + +## Abstract + +> **TODO**: Merge this section into the overview/introduction. + +The docker registry is a service to manage information about docker images and +enable their distribution. While the current registry is usable, there are +several problems with the architecture that have led to this proposal. For +relevant details, please see the following issues: + +- docker/docker#8093 +- docker/docker-registry#612 + +The main driver of this proposal are changes to the docker the image format, +covered in docker/docker#8093. The new, self-contained image manifest +simplifies the image definition and the underlying backend layout. To reduce +bandwidth usage, the new registry will be architected to avoid uploading +existing layers and will support resumable layer uploads. + +While out of scope for this specification, the URI layout of the new API will +be structured to support a rich Authentication and Authorization model by +leveraging namespaces. + +Furthermore, to bring docker registry in line with docker core, the registry is written in Go. + +## Scope + +> **TODO**: Merge this section into the overview/introduction. + +This proposal covers the URL layout and protocols of the Docker Registry V2 +JSON API. This will affect the docker core registry API and the rewrite of +docker-registry. + +This includes the following features: + +- Namespace-oriented URI Layout +- PUSH/PULL registry server for V2 image manifest format +- Resumable layer PUSH support +- V2 Client library implementation + +While authentication and authorization support will influence this +specification, details of the protocol will be left to a future specification. +Other features marked as next generation will be incorporated when the initial +support is complete. Please see the road map for details. + +## Use Cases + +> **TODO**: Merge this section into the overview/introduction. + +For the most part, the use cases of the former registry API apply to the new +version. Differentiating uses cases are covered below. + +### Resumable Push + +Company X's build servers lose connectivity to docker registry before +completing an image layer transfer. After connectivity returns, the build +server attempts to re-upload the image. The registry notifies the build server +that the upload has already been partially attempted. The build server +responds by only sending the remaining data to complete the image file. + +### Resumable Pull + +Company X is having more connectivity problems but this time in their +deployment datacenter. When downloading an image, the connection is +interrupted before completion. The client keeps the partial data and uses http +`Range` requests to avoid downloading repeated data. + +### Layer Upload De-duplication + +Company Y's build system creates two identical docker layers from build +processes A and B. Build process A completes uploading the layer before B. +When process B attempts to upload the layer, the registry indicates that its +not necessary because the layer is already known. + +If process A and B upload the same layer at the same time, both operations +will proceed and the first to complete will be stored in the registry (Note: +we may modify this to prevent dogpile with some locking mechanism). + +## Overview + +This section covers client flows and details of the API endpoints. All +endpoints will be prefixed by the API version and the repository name: + + /v2// + +For example, an API endpoint that will work with the `library/ubuntu` +repository, the URI prefix will be: + + /v2/library/ubuntu/ + +This scheme provides rich access control over various operations and methods +using the URI prefix and http methods that can be controlled in variety of +ways. + +Classically, repository names have always been two path components where each +path component is less than 30 characters. The V2 registry API does not +enforce this. The rules for a repository name are as follows: + +1. A repository name is broken up into _path components_. A component of a + repository name must be at least two characters, optionally separated by + periods, dashes or underscores. More strictly, it must match the regular + expression `[a-z0-9]+(?:[._-][a-z0-9]+)*` and the matched result must be 2 + or more characters in length. +2. The name of a repository must have at least two path components, separated + by a forward slash. +3. The total length of a repository name, including slashes, must be less the + 256 characters. + +These name requirements _only_ apply to the registry API and should accept a +superset of what is supported by other docker ecosystem components. + +All endpoints should support aggressive http caching, compression and range +headers, where appropriate. The new API attempts to leverage HTTP semantics +where possible but may break from standards to implement targeted features. + +For detail on individual endpoints, please see the _Detail_ section. + +### Errors + +Actionable failure conditions, covered in detail in their relevant sections, +are reported as part of 4xx responses, in a json response body. One or more +errors will be returned in the following format: + + { + "errors:" [{ + "code": , + "message": , + "detail": + }, + ... + ] + } + +The `code` field will be a unique identifier, all caps with underscores by +convention. The `message` field will be a human readable string. The optional +`detail` field may contain arbitrary json data providing information the +client can use to resolve the issue. + +While the client can take action on certain error codes, the registry may add +new error codes over time. All client implementations should treat unknown +error codes as `UNKNOWN`, allowing future error codes to be added without +breaking API compatibility. For the purposes of the specification error codes +will only be added and never removed. + +For a complete account of all error codes, please see the _Detail_ section. + +### API Version Check + +A minimal endpoint, mounted at `/v2/` will provide version support information +based on its response statuses. The request format is as follows: + + GET /v2/ + +If a `200 OK` response is returned, the registry implements the V2(.1) +registry API and the client may proceed safely with other V2 operations. +Optionally, the response may contain information about the supported paths in +the response body. The client should be prepared to ignore this data. + +If a `401 Unauthorized` response is returned, the client should take action +based on the contents of the "WWW-Authenticate" header and try the endpoint +again. Depending on access control setup, the client may still have to +authenticate against different resources, even if this check succeeds. + +If `404 Not Found` response status, or other unexpected status, is returned, +the client should proceed with the assumption that the registry does not +implement V2 of the API. + +### Pulling An Image + +An "image" is a combination of a JSON manifest and individual layer files. The +process of pulling an image centers around retrieving these two components. + +The first step in pulling an image is to retrieve the manifest. For reference, +the relevant manifest fields for the registry are the following: + + field | description | +----------|------------------------------------------------| +name | The name of the image. | +tag | The tag for this version of the image. | +fsLayers | A list of layer descriptors (including tarsum) | +signature | A JWS used to verify the manifest content | + +For more information about the manifest format, please see +[docker/docker#8093](https://github.com/docker/docker/issues/8093). + +When the manifest is in hand, the client must verify the signature to ensure +the names and layers are valid. Once confirmed, the client will then use the +tarsums to download the individual layers. Layers are stored in as blobs in +the V2 registry API, keyed by their tarsum digest. + +#### Pulling an Image Manifest + +The image manifest can be fetched with the following url: + +``` +GET /v2//manifests/ +``` + +The "name" and "tag" parameter identify the image and are required. + +A `404 Not Found` response will be returned if the image is unknown to the +registry. If the image exists and the response is successful, the image +manifest will be returned, with the following format (see docker/docker#8093 +for details): + + { + "name": , + "tag": , + "fsLayers": [ + { + "blobSum": + }, + ... + ] + ], + "history": , + "signature": + } + +The client should verify the returned manifest signature for authenticity +before fetching layers. + +#### Pulling a Layer + +Layers are stored in the blob portion of the registry, keyed by tarsum digest. +Pulling a layer is carried out by a standard http request. The URL is as +follows: + + GET /v2//blobs/ + +Access to a layer will be gated by the `name` of the repository but is +identified uniquely in the registry by `tarsum`. The `tarsum` parameter is an +opaque field, to be interpreted by the tarsum library. + +This endpoint may issue a 307 (302 for /blobs/uploads/ +``` + +The parameters of this request are the image namespace under which the layer +will be linked. Responses to this request are covered below. + +##### Existing Layers + +The existence of a layer can be checked via a `HEAD` request to the blob store +API. The request should be formatted as follows: + +``` +HEAD /v2//blobs/ +``` + +If the layer with the tarsum specified in `digest` is available, a 200 OK +response will be received, with no actual body content (this is according to +http specification). The response will look as follows: + +``` +200 OK +Content-Length: +``` + +When this response is received, the client can assume that the layer is +already available in the registry under the given name and should take no +further action to upload the layer. Note that the binary digests may differ +for the existing registry layer, but the tarsums will be guaranteed to match. + +##### Uploading the Layer + +If the POST request is successful, a `202 Accepted` response will be returned +with the upload URL in the `Location` header: + +``` +202 Accepted +Location: /v2//blobs/uploads/ +Range: bytes=0- +Content-Length: 0 +``` + +The rest of the upload process can be carried out with the returned url, +called the "Upload URL" from the `Location` header. All responses to the +upload url, whether sending data or getting status, will be in this format. +Though the URI format (`/v2//blobs/uploads/`) for the `Location` +header is specified, clients should treat it as an opaque url and should never +try to assemble the it. While the `uuid` parameter may be an actual UUID, this +proposal imposes no constraints on the format and clients should never impose +any. + +##### Upload Progress + +The progress and chunk coordination of the upload process will be coordinated +through the `Range` header. While this is a non-standard use of the `Range` +header, there are examples of [similar approaches](https://developers.google.c +om/youtube/v3/guides/using_resumable_upload_protocol) in APIs with heavy use. +For an upload that just started, for an example with a 1000 byte layer file, +the `Range` header would be as follows: + +``` +Range: bytes=0-0 +``` + +To get the status of an upload, issue a GET request to the upload URL: + +``` +GET /v2//blobs/uploads/ +Host: +``` + +The response will be similar to the above, except will return 204 status: + +``` +204 No Content +Location: /v2//blobs/uploads/ +Range: bytes=0- +``` + +Note that the HTTP `Range` header byte ranges are inclusive and that will be +honored, even in non-standard use cases. + +##### Monolithic Upload + +A monolithic upload is simply a chunked upload with a single chunk and may be +favored by clients that would like to avoided the complexity of chunking. To +carry out a "monolithic" upload, one can simply put the entire content blob to +the provided URL: + +``` +PUT /v2//blobs/uploads/?digest=[&digest=sha256:] +Content-Length: +Content-Type: application/octet-stream + + +``` + +The "digest" parameter must be included with the PUT request. Please see the +_Completed Upload_ section for details on the parameters and expected +responses. + +Additionally, the download can be completed with a single `POST` request to +the uploads endpoint, including the "size" and "digest" parameters: + +``` +POST /v2//blobs/uploads/?digest=[&digest=sha256:] +Content-Length: +Content-Type: application/octet-stream + + +``` + +On the registry service, this should allocate a download, accept and verify +the data and return the same response as the final chunk of an upload. If the +POST request fails collecting the data in any way, the registry should attempt +to return an error response to the client with the `Location` header providing +a place to continue the download. + +The single `POST` method is provided for convenience and most clients should +implement `POST` + `PUT` to support reliable resume of uploads. + +##### Chunked Upload + +To carry out an upload of a chunk, the client can specify a range header and +only include that part of the layer file: + +``` +PATCH /v2//blobs/uploads/ +Content-Length: +Content-Range: - +Content-Type: application/octet-stream + + +``` + +There is no enforcement on layer chunk splits other than that the server must +receive them in order. The server may enforce a minimum chunk size. If the +server cannot accept the chunk, a `416 Requested Range Not Satisfiable` +response will be returned and will include a `Range` header indicating the +current status: + +``` +416 Requested Range Not Satisfiable +Location: /v2//blobs/uploads/ +Range: 0- +Content-Length: 0 +``` + +If this response is received, the client should resume from the "last valid +range" and upload the subsequent chunk. A 416 will be returned under the +following conditions: + +- Invalid Content-Range header format +- Out of order chunk: the range of the next chunk must start immediately after + the "last valid range" from the previous response. + +When a chunk is accepted as part of the upload, a `202 Accepted` response will +be returned, including a `Range` header with the current upload status: + +``` +202 Accepted +Location: /v2//blobs/uploads/ +Range: bytes=0- +Content-Length: 0 +``` + +##### Completed Upload + +For an upload to be considered complete, the client must submit a `PUT` +request on the upload endpoint with a digest parameter. If it is not provided, +the download will not be considered complete. The format for the final chunk +will be as follows: + +``` +PUT /v2//blob/uploads/?digest=[&digest=sha256:] +Content-Length: +Content-Range: - +Content-Type: application/octet-stream + + +``` + +Optionally, if all chunks have already been uploaded, a `PUT` request with a +`digest` parameter and zero-length body may be sent to complete and validated +the upload. Multiple "digest" parameters may be provided with different +digests. The server may verify none or all of them but _must_ notify the +client if the content is rejected. + +When the last chunk is received and the layer has been validated, the client +will receive a `201 Created` response: + +``` +201 Created +Location: /v2//blobs/ +Content-Length: 0 +``` + +The `Location` header will contain the registry URL to access the accepted +layer file. + +###### Digest Parameter + +The "digest" parameter is designed as an opaque parameter to support +verification of a successful transfer. The initial version of the registry API +will support a tarsum digest, in the standard tarsum format. For example, a +HTTP URI parameter might be as follows: + +``` +tarsum.v1+sha256:6c3c624b58dbbcd3c0dd82b4c53f04194d1247c6eebdaab7c610cf7d66709b3b +``` + +Given this parameter, the registry will verify that the provided content does +result in this tarsum. Optionally, the registry can support other other digest +parameters for non-tarfile content stored as a layer. A regular hash digest +might be specified as follows: + +``` +sha256:6c3c624b58dbbcd3c0dd82b4c53f04194d1247c6eebdaab7c610cf7d66709b3b +``` + +Such a parameter would be used to verify that the binary content (as opposed +to the tar content) would be verified at the end of the upload process. + +For the initial version, registry servers are only required to support the +tarsum format. + +##### Canceling an Upload + +An upload can be cancelled by issuing a DELETE request to the upload endpoint. +The format will be as follows: + +``` +DELETE /v2//blobs/uploads/ +``` + +After this request is issued, the upload uuid will no longer be valid and the +registry server will dump all intermediate data. While uploads will time out +if not completed, clients should issue this request if they encounter a fatal +error but still have the ability to issue an http request. + +##### Errors + +If an 502, 503 or 504 error is received, the client should assume that the +download can proceed due to a temporary condition, honoring the appropriate +retry mechanism. Other 5xx errors should be treated as terminal. + +If there is a problem with the upload, a 4xx error will be returned indicating +the problem. After receiving a 4xx response (except 416, as called out above), +the upload will be considered failed and the client should take appropriate +action. + +Note that the upload url will not be available forever. If the upload uuid is +unknown to the registry, a `404 Not Found` response will be returned and the +client must restart the upload process. + +#### Pushing an Image Manifest + +Once all of the layers for an image are uploaded, the client can upload the +image manifest. An image can be pushed using the following request format: + + PUT /v2//manifests/ + + { + "name": , + "tag": , + "fsLayers": [ + { + "blobSum": + }, + ... + ] + ], + "history": , + "signature": , + ... + } + +The `name` and `tag` fields of the response body must match those specified in +the URL. + +If there is a problem with pushing the manifest, a relevant 4xx response will +be returned with a JSON error message. Please see the _PUT Manifest section +for details on possible error codes that may be returned. + +If one or more layers are unknown to the registry, `BLOB_UNKNOWN` errors are +returned. The `detail` field of the error response will have a `digest` field +identifying the missing blob, which will be a tarsum. An error is returned for +each unknown blob. The response format is as follows: + + { + "errors:" [{ + "code": "BLOB_UNKNOWN", + "message": "blob unknown to registry", + "detail": { + "digest": + } + }, + ... + ] + } + +#### Listing Image Tags + +It may be necessary to list all of the tags under a given repository. The tags +for an image repository can be retrieved with the following request: + + GET /v2//tags/list + +The response will be in the following format: + + 200 OK + Content-Type: application/json + + { + "name": , + "tags": [ + , + ... + ] + } + +For repositories with a large number of tags, this response may be quite +large, so care should be taken by the client when parsing the response to +reduce copying. + +### Deleting an Image + +An image may be deleted from the registry via its `name` and `tag`. A delete +may be issued with the following request format: + + DELETE /v2//manifests/ + +If the image exists and has been successfully deleted, the following response +will be issued: + + 202 Accepted + Content-Length: None + +If the image had already been deleted or did not exist, a `404 Not Found` +response will be issued instead. + +## Detail + +> **Note**: This section is still under construction. For the purposes of +> implementation, if any details below differ from the described request flows +> above, the section below should be corrected. When they match, this note +> should be removed. + +The behavior of the endpoints are covered in detail in this section, organized +by route and entity. All aspects of the request and responses are covered, +including headers, parameters and body formats. Examples of requests and their +corresponding responses, with success and failure, are enumerated. + +> **Note**: The sections on endpoint detail are arranged with an example +> request, a description of the request, followed by information about that +> request. + +A list of methods and URIs are covered in the table below: + +|Method|Path|Entity|Description| +-------|----|------|------------ +{{range $route := .RouteDescriptors}}{{range $method := .Methods}}| {{$method.Method}} | `{{$route.Path|prettygorilla}}` | {{$route.Entity}} | {{$method.Description}} | +{{end}}{{end}} + +The detail for each endpoint is covered in the following sections. + +### Errors + +The error codes encountered via the API are enumerated in the following table: + +|Code|Message|Description| +-------|----|------|------------ +{{range $err := .ErrorDescriptors}} `{{$err.Value}}` | {{$err.Message}} | {{$err.Description|removenewlines}} +{{end}} + +{{range $route := .RouteDescriptors}} +### {{.Entity}} + +{{.Description}} + +{{range $method := $route.Methods}} + +#### {{.Method}} {{$route.Entity}} + +{{.Description}} + +{{if .Requests}}{{range .Requests}} +##### {{.Name}} + +``` +{{$method.Method}} {{$route.Path|prettygorilla}}{{if .QueryParameters}}?{{range .QueryParameters}}{{.Name}}={{.Format}}{{end}}{{end}}{{range .Headers}} +{{.Name}}: {{.Format}}{{end}}{{if .Body.ContentType}} +Content-Type: {{.Body.ContentType}}{{end}}{{if .Body.Format}} + +{{.Body.Format}}{{end}} +``` + +{{.Description}} + +{{if or .Headers .PathParameters .QueryParameters}} +The following parameters should be specified on the request: + +|Name|Kind|Description| +|----|----|-----------| +{{range .Headers}}|`{{.Name}}`|header|{{.Description}}| +{{end}}{{range .PathParameters}}|`{{.Name}}`|path|{{.Description}}| +{{end}}{{range .QueryParameters}}|`{{.Name}}`|query|{{.Description}}| +{{end}}{{end}} + +{{if .Successes}} +{{range .Successes}} +###### On Success: {{if .Name}}{{.Name}}{{else}}{{.StatusCode | statustext}}{{end}} + +``` +{{.StatusCode}} {{.StatusCode | statustext}}{{range .Headers}} +{{.Name}}: {{.Format}}{{end}}{{if .Body.ContentType}} +Content-Type: {{.Body.ContentType}}{{end}}{{if .Body.Format}} + +{{.Body.Format}}{{end}} +``` + +{{.Description}}{{if .Headers}} +The following headers will be returned on the response: + +|Name|Description| +|----|-----------| +{{range .Headers}}|`{{.Name}}`|{{.Description}}| +{{end}}{{end}}{{end}}{{end}} + +{{if .Failures}} +{{range .Failures}} +###### On Failure: {{if .Name}}{{.Name}}{{else}}{{.StatusCode | statustext}}{{end}} + +``` +{{.StatusCode}} {{.StatusCode | statustext}}{{range .Headers}} +{{.Name}}: {{.Format}}{{end}}{{if .Body.ContentType}} +Content-Type: {{.Body.ContentType}}{{end}}{{if .Body.Format}} + +{{.Body.Format}}{{end}} +``` + +{{.Description}} +{{if .Headers}} +The following headers will be returned on the response: + +|Name|Description| +|----|-----------| +{{range .Headers}}|`{{.Name}}`|{{.Description}}| +{{end}}{{end}} + +{{if .ErrorCodes}} +The error codes that may be included in the response body are enumerated below: + +|Code|Message|Description| +-------|----|------|------------ +{{range $err := .ErrorCodes}}| `{{$err}}` | {{$err.Descriptor.Message}} | {{$err.Descriptor.Description|removenewlines}} | +{{end}} + +{{end}}{{end}}{{end}}{{end}}{{end}}{{end}} + +{{end}}