Handle nonstandard token endpoint errors

Aaron Lehmann · Aaron Lehmann · commit ec636bbfd246 · 2016-01-20T14:45:08.000-08:00
#1249 changed token fetching to parse HTTP error response bodies as serialized errcodes. However, Docker Hub's authentication endpoint does not return error bodies in this format. To work around this, convert its format into ErrCodeUnauthorized or ErrCodeUnknown. Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
diff --git a/registry/api/errcode/errors.go b/registry/api/errcode/errors.go
@@ -69,6 +69,15 @@ func (ec *ErrorCode) UnmarshalText(text []byte) error {
 	return nil
 }
 
+// WithMessage creates a new Error struct based on the passed-in info and
+// overrides the Message property.
+func (ec ErrorCode) WithMessage(message string) Error {
+	return Error{
+		Code:    ec,
+		Message: message,
+	}
+}
+
 // WithDetail creates a new Error struct based on the passed-in info and
 // set the Detail property appropriately
 func (ec ErrorCode) WithDetail(detail interface{}) Error {
diff --git a/registry/client/errors.go b/registry/client/errors.go
@@ -31,13 +31,26 @@ func (e *UnexpectedHTTPResponseError) Error() string {
 	return fmt.Sprintf("Error parsing HTTP response: %s: %q", e.ParseErr.Error(), string(e.Response))
 }
 
-func parseHTTPErrorResponse(r io.Reader) error {
+func parseHTTPErrorResponse(statusCode int, r io.Reader) error {
 	var errors errcode.Errors
 	body, err := ioutil.ReadAll(r)
 	if err != nil {
 		return err
 	}
 
+	// For backward compatibility, handle irregularly formatted
+	// messages that contain a "details" field.
+	var detailsErr struct {
+		Details string `json:"details"`
+	}
+	err = json.Unmarshal(body, &detailsErr)
+	if err == nil && detailsErr.Details != "" {
+		if statusCode == http.StatusUnauthorized {
+			return errcode.ErrorCodeUnauthorized.WithMessage(detailsErr.Details)
+		}
+		return errcode.ErrorCodeUnknown.WithMessage(detailsErr.Details)
+	}
+
 	if err := json.Unmarshal(body, &errors); err != nil {
 		return &UnexpectedHTTPResponseError{
 			ParseErr: err,
@@ -53,14 +66,14 @@ func parseHTTPErrorResponse(r io.Reader) error {
 // range.
 func HandleErrorResponse(resp *http.Response) error {
 	if resp.StatusCode == 401 {
-		err := parseHTTPErrorResponse(resp.Body)
+		err := parseHTTPErrorResponse(resp.StatusCode, resp.Body)
 		if uErr, ok := err.(*UnexpectedHTTPResponseError); ok {
 			return errcode.ErrorCodeUnauthorized.WithDetail(uErr.Response)
 		}
 		return err
 	}
 	if resp.StatusCode >= 400 && resp.StatusCode < 500 {
-		return parseHTTPErrorResponse(resp.Body)
+		return parseHTTPErrorResponse(resp.StatusCode, resp.Body)
 	}
 	return &UnexpectedHTTPStatusError{Status: resp.Status}
 }
