golang/go · error

no scheme

Error message

no scheme

What it means

validateRepoRoot parses the repo root as a URL and requires a non-empty scheme. An empty scheme means the value looks like a bare path/host rather than a fully-qualified URL (e.g. `github.com/u/r` instead of `https://github.com/u/r`).

Source

Thrown at src/cmd/go/internal/vcs/vcs.go:1108

	}
	if subdir[0] == '/' {
		return errors.New("leading slash")
	}
	if subdir[0] == '-' {
		return errors.New("leading hyphen")
	}
	return nil
}

// validateRepoRoot returns an error if repoRoot does not seem to be
// a valid URL with scheme.
func validateRepoRoot(repoRoot string) error {
	url, err := urlpkg.Parse(repoRoot)
	if err != nil {
		return err
	}
	if url.Scheme == "" {
		return errors.New("no scheme")
	}
	if url.Scheme == "file" {
		return errors.New("file scheme disallowed")
	}
	return nil
}

var fetchGroup singleflight.Group
var (
	fetchCacheMu sync.Mutex
	fetchCache   = map[string]fetchResult{} // key is metaImportsForPrefix's importPrefix
)

// metaImportsForPrefix takes a package's root import path as declared in a <meta> tag
// and returns its HTML discovery URL and the parsed metaImport lines
// found on the page.
//
// The importPath is of the form "golang.org/x/tools".

View on GitHub (pinned to b6b368adc5)

Solutions

1. Add a scheme (https, git, ssh) to the repo root in the meta tag.
2. Fix the vanity server to emit fully-qualified URLs.

Example fix

<!-- before -->
<meta name="go-import" content="example.com git github.com/u/r">
<!-- after -->
<meta name="go-import" content="example.com git https://github.com/u/r">

// Ensure vanity repo roots carry a scheme.
func validRepoRoot(root string) error {
    u, err := url.Parse(root)
    if err != nil { return err }
    if u.Scheme == "" { return errors.New("repo root needs a scheme (https/git/ssh)") }
    return nil
}

null

null

When it happens

Trigger: A vanity meta tag or VCS path config supplies a repo root with no scheme.

Common situations: Hand-authored `<meta name="go-import">` tags missing the protocol; legacy vanity servers.

Related errors

• file scheme disallowed
• leading slash
• import path does not begin with hostname
• leading hyphen
• value is neither 'auto' nor a valid bool

AI-assisted analysis of golang/go@b6b368adc5 (2026-08-12). Data as JSON: /api/errors/d7c467c9e4afd9e3. Report an issue: GitHub.