GoogleContainerTools/skaffold · error

opening %s: %w

Error message

opening %s: %w

What it means

After ensuring directories exist, SaveEventsToFile opens the target file with O_APPEND|O_WRONLY|O_CREATE (mode 0600). If os.OpenFile fails, the error is wrapped as 'opening %s'. At this point directories exist, so failures are about the final file itself.

Source

Thrown at pkg/skaffold/event/event.go:841

			TerminationEvent: &proto.TerminationEvent{
				Status: Failed,
				Err:    sErrors.ActionableErr(handler.cfg, constants.Init, err),
			},
		},
	})
}

// SaveEventsToFile saves the current event log to the filepath provided
func SaveEventsToFile(fp string) error {
	handler.logLock.Lock()
	// Ensure that the filepath provided has the directories available when attemping to save the file.
	dir := filepath.Dir(fp)
	if err := os.MkdirAll(dir, 0700); err != nil {
		return fmt.Errorf("unable to create directory %q: %w", dir, err)
	}
	f, err := os.OpenFile(fp, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0600)
	if err != nil {
		return fmt.Errorf("opening %s: %w", fp, err)
	}
	defer f.Close()
	marshaller := jsonpb.Marshaler{}
	for _, ev := range handler.eventLog {
		contents := bytes.NewBuffer([]byte{})
		if err := marshaller.Marshal(contents, ev); err != nil {
			return fmt.Errorf("marshalling event: %w", err)
		}
		if _, err := f.WriteString(contents.String() + "\n"); err != nil {
			return fmt.Errorf("writing string: %w", err)
		}
	}
	handler.logLock.Unlock()
	return nil
}

View on GitHub (pinned to a1189de023)

Solutions

1. Confirm the fp argument points to a file, not a directory (append a filename if a directory was given)
2. Check write permission on the parent directory for the current user
3. Shorten the path or move the destination to a shallower directory if ENAMETOOLONG
4. Read the wrapped syscall error to identify the exact cause

Example fix

// before
SaveEventsToFile("/var/log/skaffold")
// after
SaveEventsToFile("/var/log/skaffold/events.json")

if info, err := os.Stat(fp); err == nil && info.IsDir() {
    return fmt.Errorf("event log path %q is a directory", fp)
}

if err := SaveEventsToFile(fp); err != nil {
    if strings.Contains(err.Error(), "opening ") {
        alt := filepath.Join(os.TempDir(), "skaffold-events.json")
        log.Warnf("cannot open %s, falling back to %s", fp, alt)
        return SaveEventsToFile(alt)
    }
    return err
}

When it happens

Trigger: The final path component is an existing directory (EISDIR); the parent directory is not writable (EACCES); the path is too long (ENAMETOOLONG); or a symlink loop exists at the target path.

Common situations: User passes a directory instead of a file path as the save destination; security software or AppArmor blocks file creation; the 0600 mode conflicts with restrictive umask expectations on shared systems.

Understand the failure class

Background: Permission denied / not authorized / 403 Forbidden: access-control rejections when the caller lacks the required role, grant, or ownership — this error's family across 18 libraries.

Related errors

• opening %s: %w
• unable to create directory %q: %w
• writing string: %w
• unable to create directory %q: %w
• writing string: %w

AI-assisted analysis of GoogleContainerTools/skaffold@a1189de023 (2026-09-05). Data as JSON: /api/errors/f6f3f8674252e074. Report an issue: GitHub.