Files
govoplan-core/src/govoplan_core/server/config.py

115 lines
4.6 KiB
Python

from __future__ import annotations
import os
import re
from collections.abc import Callable, Iterable, Mapping, Sequence
from dataclasses import dataclass, field
from importlib import import_module
from typing import Any
from fastapi import APIRouter, FastAPI
from govoplan_core.core.modules import ModuleManifest
from govoplan_core.core.registry import PlatformRegistry
from govoplan_core.server.fastapi import LifespanFactory
ManifestFactory = Callable[[], ModuleManifest]
RouterEnabled = Callable[[object | None, PlatformRegistry], bool]
AppConfigurator = Callable[[FastAPI, PlatformRegistry, object | None], None]
DEFAULT_TRUSTED_IMPORT_PREFIXES = ("govoplan_core", "govoplan_", "app")
TRUSTED_IMPORT_PREFIXES_ENV = "GOVOPLAN_TRUSTED_IMPORT_PREFIXES"
_MODULE_PATH_RE = re.compile(r"^[A-Za-z_][A-Za-z0-9_]*(?:\.[A-Za-z_][A-Za-z0-9_]*)*$")
_ATTRIBUTE_PATH_RE = re.compile(r"^[A-Za-z][A-Za-z0-9_]*(?:\.[A-Za-z][A-Za-z0-9_]*)*$")
@dataclass(frozen=True, slots=True)
class RouterContribution:
router: APIRouter
required_module: str | None = None
enabled: RouterEnabled | None = None
def should_include(self, settings: object | None, registry: PlatformRegistry) -> bool:
if self.required_module and not registry.has_module(self.required_module):
return False
if self.enabled is not None and not self.enabled(settings, registry):
return False
return True
@dataclass(frozen=True, slots=True)
class GovoplanServerConfig:
title: str = "GovOPlaN Server"
version: str = "0.1.0"
settings: object | None = None
enabled_modules: str | Iterable[str] = ("access",)
api_prefix: str = "/api/v1"
base_routers: Sequence[APIRouter] = ()
post_module_routers: Sequence[APIRouter] = ()
extra_routers: Sequence[RouterContribution] = ()
lifespan: LifespanFactory | None = None
cors_origins: Iterable[str] = ()
manifest_factories: Sequence[ManifestFactory] = ()
module_context_data: Mapping[str, Any] = field(default_factory=dict)
app_configurators: Sequence[AppConfigurator] = ()
def import_object(path: str) -> Any:
module_name, attribute = validate_object_path(path)
_validate_trusted_import_prefix(module_name, trusted_import_prefixes())
module = import_module(module_name) # nosemgrep: python.lang.security.audit.non-literal-import.non-literal-import
value: Any = module
for part in attribute.split("."):
value = getattr(value, part)
return value
def validate_object_path(path: str) -> tuple[str, str]:
module_name, separator, attribute = path.strip().partition(":")
if not separator:
raise ValueError(f"Object path must use module:attribute syntax: {path!r}")
if not _MODULE_PATH_RE.fullmatch(module_name):
raise ValueError(f"Object path module is not a valid Python module path: {path!r}")
if not _ATTRIBUTE_PATH_RE.fullmatch(attribute) or any(part.startswith("_") for part in attribute.split(".")):
raise ValueError(f"Object path attribute is not a public attribute path: {path!r}")
return module_name, attribute
def trusted_import_prefixes() -> tuple[str, ...]:
configured = os.getenv(TRUSTED_IMPORT_PREFIXES_ENV, "").strip()
if not configured:
return DEFAULT_TRUSTED_IMPORT_PREFIXES
prefixes = tuple(item.strip() for item in configured.split(",") if item.strip())
return prefixes or DEFAULT_TRUSTED_IMPORT_PREFIXES
def _validate_trusted_import_prefix(module_name: str, prefixes: Iterable[str]) -> None:
if any(_module_matches_prefix(module_name, prefix) for prefix in prefixes):
return
raise ValueError(
f"Object path module {module_name!r} is outside trusted import prefixes. "
f"Set {TRUSTED_IMPORT_PREFIXES_ENV} to allow custom deployment config modules."
)
def _module_matches_prefix(module_name: str, prefix: str) -> bool:
cleaned = prefix.strip()
if not cleaned:
return False
if cleaned.endswith((".", "_")):
return module_name.startswith(cleaned)
return module_name == cleaned or module_name.startswith(f"{cleaned}.")
def load_server_config(path: str | None = None) -> GovoplanServerConfig:
config_path = path or os.getenv("GOVOPLAN_SERVER_CONFIG") or "govoplan_core.server.default_config:get_server_config"
try:
loaded = import_object(config_path)
except ModuleNotFoundError:
if path or os.getenv("GOVOPLAN_SERVER_CONFIG"):
raise
return GovoplanServerConfig()
config = loaded() if callable(loaded) else loaded
if not isinstance(config, GovoplanServerConfig):
raise TypeError(f"{config_path!r} did not return a GovoplanServerConfig")
return config