sgl-project/sglang · error · AttributeError

module {__name__!r} has no attribute {name!r}

Error message

module {__name__!r} has no attribute {name!r}

What it means

envs.py uses a module-level __getattr__ for lazy evaluation of SGLANG_* environment variables. Accessing any attribute of sglang.multimodal_gen.envs that is not a key in environment_variables raises AttributeError instead of returning a lazy value.

Source

Thrown at python/sglang/multimodal_gen/envs.py:410

# Special handling for boolean secondary var (TaylorSeer)
def _secondary_taylorseer_getter():
    return get_bool_env_var(
        "SGLANG_CACHE_DIT_SECONDARY_TAYLORSEER",
        default=os.getenv("SGLANG_CACHE_DIT_TAYLORSEER", "false"),
    )


environment_variables["SGLANG_CACHE_DIT_SECONDARY_TAYLORSEER"] = (
    _secondary_taylorseer_getter
)


# end-env-vars-definition
def __getattr__(name: str):
    # lazy evaluation of environment variables
    if name in environment_variables:
        return environment_variables[name]()
    raise AttributeError(f"module {__name__!r} has no attribute {name!r}")


def __dir__():
    return list(environment_variables.keys())

View on GitHub (pinned to 0132848349)

Solutions

1. Check the environment_variables dict in python/sglang/multimodal_gen/envs.py for the exact accessor name
2. Read the value from os.environ directly if it's not exposed as a lazy accessor
3. Update to/from renamed accessors after version changes (consult the end-env-vars-definition section)

Example fix

# before
value = envs.SGLANG_SOME_REMOVED_VAR  # AttributeError
# after
value = os.environ.get("SGLANG_SOME_REMOVED_VAR", default)

from sglang.multimodal_gen import envs
name = "SGLANG_MY_VAR"
if name not in dir(envs):  # __dir__ lists environment_variables keys
    value = os.environ.get(name)  # fallback to raw env
else:
    value = getattr(envs, name)

def env_or_raw(name: str, default=None):
    try:
        return getattr(envs, name)
    except AttributeError:
        return os.environ.get(name, default)

try:
    val = getattr(envs, "SGLANG_MY_VAR")
except AttributeError:
    val = os.environ.get("SGLANG_MY_VAR", default)

When it happens

Trigger: `from sglang.multimodal_gen import envs` then `envs.SOME_NAME` where SOME_NAME is not defined in the environment_variables dict (e.g. removed, renamed, or never-defined variable, or accessing a real module attribute like envs.os).

Common situations: Upgrading sglang where an env var was renamed/removed; typos in env var names; assuming every SGLANG_* string has a Python accessor; accessing non-env module attributes through this module.

Understand the failure class

Background: "environment variable is not set" and "Missing keys in environment" errors: what missing required env var messages mean and how to fix them — this error's family across 28 libraries.

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AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/7f0601be10d51490. Report an issue: GitHub.