docker: expand use of UnexpectedHTTPStatusError

So that callers can actually check the status code of all requests if
needed. This changes error text slightly but I think it still carries
the same meaning.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

docker/docker_client.go

@@ -996,7 +996,7 @@ func (c *dockerClient) getExternalBlob(ctx context.Context, urls []string) (io.R
 			continue
 		}
 		if resp.StatusCode != http.StatusOK {
-			err := fmt.Errorf("error fetching external blob from %q: %d (%s)", u, resp.StatusCode, http.StatusText(resp.StatusCode))
+			err := fmt.Errorf("error fetching external blob from %q: %w", u, newUnexpectedHTTPStatusError(resp))
 			remoteErrors = append(remoteErrors, err)
 			logrus.Debug(err)
 			resp.Body.Close()

docker/docker_image_src.go

@@ -569,7 +569,7 @@ func (s *dockerImageSource) getOneSignature(ctx context.Context, sigURL *url.URL
 			logrus.Debugf("... got status 404, as expected = end of signatures")
 			return nil, true, nil
 		} else if res.StatusCode != http.StatusOK {
-			return nil, false, fmt.Errorf("reading signature from %s: status %d (%s)", sigURL.Redacted(), res.StatusCode, http.StatusText(res.StatusCode))
+			return nil, false, fmt.Errorf("reading signature from %s: %w", sigURL.Redacted(), newUnexpectedHTTPStatusError(res))
 		}
 
 		contentType := res.Header.Get("Content-Type")

docker/errors.go

@@ -40,10 +40,10 @@ func httpResponseToError(res *http.Response, context string) error {
 		err := registryHTTPResponseToError(res)
 		return ErrUnauthorizedForCredentials{Err: err}
 	default:
-		if context != "" {
-			context += ": "
+		if context == "" {
+			return newUnexpectedHTTPStatusError(res)
 		}
-		return fmt.Errorf("%sinvalid status code from registry %d (%s)", context, res.StatusCode, http.StatusText(res.StatusCode))
+		return fmt.Errorf("%s: %w", context, newUnexpectedHTTPStatusError(res))
 	}
 }