llama-stack-mirror/llama_stack/distribution/request_headers.py

116 lines
3.6 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.
import contextvars
import json
import logging
from contextlib import AbstractContextManager
from typing import Any
from .utils.dynamic import instantiate_class_type
log = logging.getLogger(__name__)
# Context variable for request provider data and auth attributes
PROVIDER_DATA_VAR = contextvars.ContextVar("provider_data", default=None)
class RequestProviderDataContext(AbstractContextManager):
"""Context manager for request provider data"""
def __init__(
self,
provider_data: dict[str, Any] | None = None,
auth_attributes: dict[str, list[str]] | None = None,
logged_in_user: str | None = None,
):
self.provider_data = provider_data or {}
if auth_attributes:
self.provider_data["__auth_attributes"] = auth_attributes
if logged_in_user:
self.provider_data["__logged_in_user"] = logged_in_user
self.token = None
def __enter__(self):
# Save the current value and set the new one
self.token = PROVIDER_DATA_VAR.set(self.provider_data)
return self
def __exit__(self, exc_type, exc_val, exc_tb):
# Restore the previous value
if self.token is not None:
PROVIDER_DATA_VAR.reset(self.token)
class NeedsRequestProviderData:
def get_request_provider_data(self) -> Any:
spec = self.__provider_spec__
if not spec:
raise ValueError(f"Provider spec not set on {self.__class__}")
provider_type = spec.provider_type
validator_class = spec.provider_data_validator
if not validator_class:
raise ValueError(f"Provider {provider_type} does not have a validator")
val = PROVIDER_DATA_VAR.get()
if not val:
return None
validator = instantiate_class_type(validator_class)
try:
provider_data = validator(**val)
return provider_data
except Exception as e:
log.error(f"Error parsing provider data: {e}")
return None
def parse_request_provider_data(headers: dict[str, str]) -> dict[str, Any] | None:
"""Parse provider data from request headers"""
keys = [
"X-LlamaStack-Provider-Data",
"x-llamastack-provider-data",
]
val = None
for key in keys:
val = headers.get(key, None)
if val:
break
if not val:
return None
try:
return json.loads(val)
except json.JSONDecodeError:
log.error("Provider data not encoded as a JSON object!")
return None
def request_provider_data_context(
headers: dict[str, str],
auth_attributes: dict[str, list[str]] | None = None,
logged_in_user: str | None = None,
) -> AbstractContextManager:
"""Context manager that sets request provider data from headers and auth attributes for the duration of the context"""
provider_data = parse_request_provider_data(headers)
return RequestProviderDataContext(provider_data, auth_attributes, logged_in_user)
def get_auth_attributes() -> dict[str, list[str]] | None:
"""Helper to retrieve auth attributes from the provider data context"""
provider_data = PROVIDER_DATA_VAR.get()
if not provider_data:
return None
return provider_data.get("__auth_attributes")
def get_logged_in_user() -> str | None:
"""Helper to retrieve logged in user from the provider data context"""
provider_data = PROVIDER_DATA_VAR.get()
return provider_data.get("__logged_in_user")