feat: propagate detailed error msgs to client (OCI dist-spec format) (#1681)

Signed-off-by: Alexei Dodon <adodon@cisco.com>

pkg/api/errors/errors.go

@@ -5,16 +5,10 @@ import (
 )
 
 type Error struct {
-	Code        string      `json:"code"`
-	Message     string      `json:"message"`
-	Description string      `json:"description"`
-	Detail      interface{} `json:"detail,omitempty"`
-}
-
-func (e Error) WithMessage(msg string) Error {
-	e.Message = msg
-
-	return e
+	Code        string            `json:"code"`
+	Message     string            `json:"message"`
+	Description string            `json:"-"`
+	Detail      map[string]string `json:"detail"`
 }
 
 type ErrorList struct {
@@ -66,7 +60,7 @@ func (e ErrorCode) String() string {
 	return errMap[e]
 }
 
-func NewError(code ErrorCode, detail ...interface{}) Error {
+func NewError(code ErrorCode) *Error {
 	errMap := map[ErrorCode]Error{
 		BLOB_UNKNOWN: {
 			Message: "blob unknown to registry",
@@ -77,12 +71,12 @@ func NewError(code ErrorCode, detail ...interface{}) Error {
 
 		BLOB_UPLOAD_INVALID: {
 			Message:     "blob upload invalid",
-			Description: `The blob upload encountered an error and can no longer proceed.`,
+			Description: "The blob upload encountered an error and can no longer proceed.",
 		},
 
 		BLOB_UPLOAD_UNKNOWN: {
 			Message:     "blob upload unknown to registry",
-			Description: `If a blob upload has been cancelled or was never started, this error code MAY be returned.`,
+			Description: "If a blob upload has been cancelled or was never started, this error code MAY be returned.",
 		},
 
 		DIGEST_INVALID: {
@@ -94,71 +88,68 @@ func NewError(code ErrorCode, detail ...interface{}) Error {
 		},
 
 		MANIFEST_BLOB_UNKNOWN: {
-			Message: "blob unknown to registry",
-			Description: `This error MAY be returned when a manifest blob is unknown
-			to the registry.`,
+			Message:     "blob unknown to registry",
+			Description: "This error MAY be returned when a manifest blob is unknown to the registry.",
 		},
 
 		MANIFEST_INVALID: {
 			Message: "manifest invalid",
-			Description: `During upload, manifests undergo several checks ensuring
-			validity. If those checks fail, this error MAY be returned, unless a more
-			specific error is included. The detail will contain information the failed
-			validation.`,
+			Description: "During upload, manifests undergo several checks ensuring " +
+				"validity. If those checks fail, this error MAY be returned, unless a more " +
+				"specific error is included. The detail will contain information the failed validation.",
 		},
 
 		MANIFEST_UNKNOWN: {
 			Message: "manifest unknown",
-			Description: `This error is returned when the manifest, identified by name
-			and tag is unknown to the repository.`,
+			Description: "This error is returned when the manifest, identified by name " +
+				"and tag is unknown to the repository.",
 		},
 
 		MANIFEST_UNVERIFIED: {
 			Message: "manifest failed signature verification",
-			Description: `During manifest upload, if the manifest fails signature
-			verification, this error will be returned.`,
+			Description: "During manifest upload, if the manifest fails signature " +
+				"verification, this error will be returned.",
 		},
 
 		NAME_INVALID: {
 			Message: "invalid repository name",
-			Description: `Invalid repository name encountered either during manifest
-			validation or any API operation.`,
+			Description: "Invalid repository name encountered either during manifest " +
+				"validation or any API operation.",
 		},
 
 		NAME_UNKNOWN: {
 			Message:     "repository name not known to registry",
-			Description: `This is returned if the name used during an operation is unknown to the registry.`,
+			Description: "This is returned if the name used during an operation is unknown to the registry.",
 		},
 
 		SIZE_INVALID: {
 			Message: "provided length did not match content length",
-			Description: "When a layer is uploaded, the provided size will be checked against the uploaded " +
-				"content. If they do not match, this error will be returned.",
+			Description: "When a layer is uploaded, the provided size will be checked against " +
+				"the uploaded content. If they do not match, this error will be returned.",
 		},
 
 		TAG_INVALID: {
 			Message: "manifest tag did not match URI",
-			Description: `During a manifest upload, if the tag in the manifest does
-			not match the uri tag, this error will be returned.`,
+			Description: "During a manifest upload, if the tag in the manifest does " +
+				"not match the uri tag, this error will be returned.",
 		},
 
 		UNAUTHORIZED: {
 			Message: "authentication required",
-			Description: `The access controller was unable to authenticate the client.
-			Often this will be accompanied by a Www-Authenticate HTTP response header
-			indicating how to authenticate.`,
+			Description: "The access controller was unable to authenticate the client." +
+				"Often this will be accompanied by a Www-Authenticate HTTP response header " +
+				"indicating how to authenticate.",
 		},
 
 		DENIED: {
-			Message: "requested access to the resource is denied",
-			Description: `The access controller denied access for the operation on a
-			resource.`,
+			Message:     "requested access to the resource is denied",
+			Description: "The access controller denied access for the operation on a resource.",
 		},
 
 		UNSUPPORTED: {
 			Message: "The operation is unsupported.",
-			Description: `The operation was unsupported due to a missing
-			implementation or invalid set of parameters.`,
+			Description: "The operation was unsupported due to a missing " +
+				"implementation or invalid set of parameters.",
 		},
 
 		INVALID_INDEX: {
@@ -173,19 +164,24 @@ func NewError(code ErrorCode, detail ...interface{}) Error {
 	}
 
 	err.Code = code.String()
-	err.Detail = detail
+	err.Detail = map[string]string{
+		"description": err.Description,
+	}
+
+	return &err
+}
+
+func (err *Error) AddDetail(m map[string]string) *Error {
+	for k, v := range m {
+		err.Detail[k] = v
+	}
 
 	return err
 }
 
-func NewErrorList(errors ...Error) ErrorList {
-	errList := make([]*Error, 0)
-	err := Error{}
-
-	for _, e := range errors {
-		err = e
-		errList = append(errList, &err)
-	}
+func NewErrorList(errors ...*Error) ErrorList {
+	var errList []*Error
+	errList = append(errList, errors...)
 
 	return ErrorList{errList}
 }

pkg/api/errors/errors_test.go

@@ -10,6 +10,6 @@ import (
 
 func TestUnknownCodeError(t *testing.T) {
 	Convey("Retrieve a new error with unknown code", t, func() {
-		So(func() { _ = apiErr.NewError(123456789, nil) }, ShouldPanic)
+		So(func() { _ = apiErr.NewError(123456789) }, ShouldPanic)
 	})
 }