sgl-project/sglang · error · ValueError

allowed media domains cannot be empty

Error message

allowed media domains cannot be empty

What it means

After stripping whitespace and trailing dots, an allowed-media-domains entry became an empty string. The normalizer strips leading/trailing whitespace and a single trailing dot (DNS root form), so inputs like ' ' or '.' normalize to nothing and are rejected because an empty allowlist entry would match nothing and usually indicates a config typo.

Source

Thrown at python/sglang/srt/utils/common.py:1526

        torch.xpu.manual_seed_all(seed)


_mm_http_session = threading.local()

_DEFAULT_MEDIA_URL_MAX_FILE_SIZE_MB = 64
_MAX_MEDIA_URL_REDIRECTS = 5
_MEDIA_URL_REDIRECT_STATUS_CODES = {301, 302, 303, 307, 308}
_allowed_media_domains: frozenset[str] = frozenset()
_media_url_max_file_size_bytes = _DEFAULT_MEDIA_URL_MAX_FILE_SIZE_MB * 1024 * 1024


def _normalize_media_domain(domain: str) -> str:
    if not isinstance(domain, str):
        raise ValueError("allowed media domains must be strings")

    domain = domain.strip().rstrip(".")
    if not domain:
        raise ValueError("allowed media domains cannot be empty")
    if "://" in domain or any(char in domain for char in "/?#@"):
        raise ValueError(
            f"Invalid allowed media domain {domain!r}: provide a hostname only"
        )

    # Brackets are URL syntax, not part of an IPv6 hostname.
    if domain.startswith("[") and domain.endswith("]"):
        domain = domain[1:-1]
    try:
        return str(ipaddress.ip_address(domain))
    except ValueError:
        if ":" in domain:
            raise ValueError(
                f"Invalid allowed media domain {domain!r}: ports are not supported"
            )

    try:
        normalized = domain.encode("idna").decode("ascii").lower()

View on GitHub (pinned to 0132848349)

Solutions

1. Strip and filter empty entries when parsing user input: [d for d in raw.split(',') if d.strip()]
2. Fix the typo in the config file / CLI flag
3. Validate the allowlist before server start

Example fix

# before
configure_media_url_security(allowed_media_domains=['example.com', '', ''])
# after
configure_media_url_security(allowed_media_domains=[d for d in ['example.com', '', ''] if d.strip()])

domains = [d.strip().rstrip('.') for d in raw.split(',')]
domains = [d for d in domains if d]  # drop empties before configure()

When it happens

Trigger: configure_media_url_security(allowed_media_domains=['', ' .', '.']) — entry reduces to empty after domain.strip().rstrip('.').

Common situations: Comma-splitting a user-supplied --allowed-media-domains value with trailing commas ('a.com,,b.com'); copy-paste config with stray dots; empty strings from YAML list entries.

Understand the failure class

Background: Config validation failed: what "invalid value for {key}" and settings-rejection errors mean across 19 open-source libraries — this error's family across 19 libraries.

Related errors

• media_url_max_file_size_mb must be non-negative
• allowed media domains must be strings
• Invalid allowed media domain {domain!r}: provide a hostname
• Invalid allowed media domain {domain!r}: ports are not suppo
• Invalid allowed media domain {domain!r}

AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/0393a0d0e3d44746. Report an issue: GitHub.