kubernetes/kops · error

downloading %q: %w

Error message

downloading %q: %w

What it means

In generatefileassets (a code-generation tool that turns remote SHA256SUMS files into embedded YAML manifests), run() fetches the hash file with http.Get. This error wraps any transport-level failure: DNS resolution, TCP connect, TLS, timeouts, or an invalid URL scheme. It does not cover HTTP error statuses (see 806).

Source

Thrown at pkg/assets/assetdata/tools/cmd/generatefileassets/main.go:58

	filestoreBase := ""
	prefix := ""
	hashFileURL := ""
	var exclude globList

	flag.StringVar(&filestoreBase, "base", filestoreBase, "base directory")
	flag.StringVar(&prefix, "prefix", prefix, "prefix to fetch")
	flag.StringVar(&hashFileURL, "sums", hashFileURL, "prefix to fetch")
	flag.Var(&exclude, "exclude", "path-globs to exclude from output")

	flag.Parse()

	if hashFileURL == "" {
		hashFileURL = filestoreBase + prefix + "SHA256SUMS"
	}

	httpResponse, err := http.Get(hashFileURL)
	if err != nil {
		return fmt.Errorf("downloading %q: %w", hashFileURL, err)
	}
	if httpResponse.StatusCode != 200 {
		return fmt.Errorf("unexpected status getting %q: %v", hashFileURL, httpResponse.Status)
	}
	defer httpResponse.Body.Close()

	b, err := io.ReadAll(httpResponse.Body)
	if err != nil {
		return fmt.Errorf("reading body %q: %w", hashFileURL, err)
	}

	m := &manifest{}
	for _, line := range strings.Split(string(b), "\n") {
		line = strings.TrimSpace(line)
		if line == "" {
			continue
		}
		if line == "-----BEGIN PGP SIGNED MESSAGE-----" {

View on GitHub (pinned to 4c8573c808)

Solutions

1. Verify the URL (curl the hashFileURL printed in the error) and fix -base/-prefix/-sums flags
2. Include the scheme in -sums, e.g. -sums https://storage.googleapis.com/.../SHA256SUMS
3. Check network/proxy: set HTTPS_PROXY or run from a machine with internet access
4. Retry if transient (DNS blip, rate limit); the tool does no retries itself

Example fix

// before
main -base storage.googleapis.com/kops-ci/bin/ -prefix 1.28.0/
// after (note scheme)
main -base https://storage.googleapis.com/kops-ci/bin/ -prefix 1.28.0/

u, err := url.Parse(hashFileURL)
if err != nil || (u.Scheme != "http" && u.Scheme != "https") || u.Host == "" {
	return fmt.Errorf("invalid hash file URL: %q", hashFileURL)
}

resp, err := http.Get(hashFileURL)
if err != nil {
	var netErr net.Error
	if errors.As(err, &netErr) && netErr.Timeout() {
		// retry with backoff
	}
	return fmt.Errorf("downloading %q: %w", hashFileURL, err)
}

When it happens

Trigger: Running the tool with a -base/-prefix/-sums combination producing a URL that fails http.Get — unreachable host, no network, DNS failure, offline CI, or malformed URL (e.g. missing scheme when -sums is given a bare hostname).

Common situations: CI runner without internet access; typo'd or stale filestore base; corporate proxy/firewall blocking storage.googleapis.com; passing -sums without http(s):// prefix.

Understand the failure class

Background: 'Something went wrong' / 'Request failed (500)' / 'HTTP error! status: 404' — what failed HTTP requests actually mean and how to find the real cause — this error's family across 28 libraries.

Related errors

• error reading tag file %q: %v
• droplet metadata returned non-200 status code: %d
• fetching metadata from '%s' returned status code '%d'
• error fetching %q: %v
• error reading response for %q: %v

AI-assisted analysis of kubernetes/kops@4c8573c808 (2026-09-05). Data as JSON: /api/errors/12b7965b1a6663f3. Report an issue: GitHub.