gastownhall/beads · error

failed to get hostname: %w

Error message

failed to get hostname: %w

What it means

GetCloneIDForPath builds a clone identifier from hostname + normalized main repo path. Its first step is os.Hostname(); if the OS cannot report a hostname, the failure is wrapped as "failed to get hostname". Without a hostname the clone ID would not be unique per machine, so bd refuses to guess.

Source

Thrown at internal/beads/fingerprint.go:155

	}

	return filepath.ToSlash(evalPath), nil
}

// GetCloneID generates a unique ID for this specific clone (not shared with other clones)
func GetCloneID() (string, error) {
	return GetCloneIDForPath("")
}

// GetCloneIDForPath generates a unique ID for the specific clone rooted at or
// containing repoPath. An empty repoPath uses the current cwd.
//
// GH#2867: Uses the main repo root (not worktree root) so that all worktrees
// sharing a database produce the same clone ID.
func GetCloneIDForPath(repoPath string) (string, error) {
	hostname, err := os.Hostname()
	if err != nil {
		return "", fmt.Errorf("failed to get hostname: %w", err)
	}

	repoRoot, err := mainRepoRootForPath(repoPath)
	if err != nil {
		return "", fmt.Errorf("not a git repository: %w", err)
	}

	normalizedPath := normalizedRepoPath(repoRoot)
	hash := sha256.Sum256([]byte(hostname + ":" + normalizedPath))
	return hex.EncodeToString(hash[:8]), nil
}

func runGitInRepo(repoPath string, args ...string) ([]byte, error) {
	cmd := exec.Command("git", args...)
	if repoPath != "" {
		cmd.Dir = repoPath
	}
	return cmd.Output()

View on GitHub (pinned to 71377f2769)

Solutions

1. Set a hostname for the environment (e.g. `hostnamectl set-hostname myhost` or Docker `--hostname myhost`)
2. Fix /etc/hostname (or the platform equivalent) and restart the process
3. Check sandbox/seccomp policies that block uname/gethostname syscalls
4. If it is transient, retry — os.Hostname failures are rarely retriable but a container restart usually resolves it

Example fix

// docker run before
$ docker run acme/bd
// after
$ docker run --hostname devbox acme/bd

if _, err := os.Hostname(); err != nil {
    // fix environment hostname before using clone-ID APIs
}

cloneID, err := beads.GetCloneIDForPath(path)
if err != nil && strings.Contains(err.Error(), "failed to get hostname") {
    return fmt.Errorf("set a hostname for this environment: %w", err)
}

When it happens

Trigger: Calling GetCloneID/GetCloneIDForPath on a system where os.Hostname() returns an error — severely restricted environments, containers with no set hostname, or exotic sandboxes where the utsname is unavailable.

Common situations: Minimal containers/chroots without a configured hostname; hardened sandboxes blocking uname; embedded systems with unset machine names; test environments faking syscalls.

Related errors

• applying %s: %w
• not a git repository: %w
• %s:// URL must include a hostname

AI-assisted analysis of gastownhall/beads@71377f2769 (2026-08-30). Data as JSON: /api/errors/b9dfd946b52b6738. Report an issue: GitHub.