feat: declare governed external provider state

This commit is contained in:
2026-08-01 17:48:32 +02:00
parent f084a0f3a9
commit 233ce40983
8 changed files with 430 additions and 366 deletions
+24 -338
View File
@@ -1,346 +1,32 @@
from __future__ import annotations
from dataclasses import dataclass, field
from pathlib import Path
from typing import Iterable, Protocol
from govoplan_core.security.outbound_http import (
OutboundHttpError,
response_limit,
validate_unpinned_sdk_http_url,
from govoplan_core.core.object_storage import (
LocalFilesystemStorageBackend,
S3StorageBackend,
StorageBackend,
StorageBackendError,
StorageObjectInfo,
StorageObjectMissing,
StorageObjectPage,
configured_storage_backend,
)
from govoplan_files.backend.runtime import settings
class StorageBackendError(RuntimeError):
pass
class StorageObjectMissing(StorageBackendError):
pass
@dataclass(frozen=True, slots=True)
class StorageObjectInfo:
key: str
size_bytes: int
@dataclass(frozen=True, slots=True)
class StorageObjectPage:
objects: tuple[StorageObjectInfo, ...]
next_cursor: str | None = None
class StorageBackend(Protocol):
name: str
def put_bytes(self, key: str, data: bytes, *, content_type: str | None = None) -> None: ...
def get_bytes(self, key: str) -> bytes: ...
def iter_bytes(self, key: str, *, chunk_size: int = 1024 * 1024) -> Iterable[bytes]: ...
def delete(self, key: str) -> None: ...
def exists(self, key: str) -> bool: ...
def stat(self, key: str) -> StorageObjectInfo: ...
def list_objects(
self,
*,
prefix: str,
after: str | None = None,
limit: int = 500,
) -> StorageObjectPage: ...
@dataclass(slots=True)
class LocalFilesystemStorageBackend:
root: Path
fallback_roots: tuple[Path, ...] = field(default_factory=tuple)
name: str = "local"
def __post_init__(self) -> None:
self.root = self.root.expanduser().resolve()
self.fallback_roots = tuple(root.expanduser().resolve() for root in self.fallback_roots if root)
self.root.mkdir(parents=True, exist_ok=True)
def _path_for_root(self, root: Path, key: str) -> Path:
path = (root / key).resolve()
if not path.is_relative_to(root):
raise StorageBackendError("Storage key escapes local storage root")
return path
def _path(self, key: str) -> Path:
return self._path_for_root(self.root, key)
def _readable_path(self, key: str) -> Path:
primary = self._path(key)
if primary.exists() and primary.is_file():
return primary
for root in self.fallback_roots:
candidate = self._path_for_root(root, key)
if candidate.exists() and candidate.is_file():
return candidate
raise StorageObjectMissing("Stored object does not exist")
def put_bytes(self, key: str, data: bytes, *, content_type: str | None = None) -> None:
path = self._path(key)
path.parent.mkdir(parents=True, exist_ok=True)
path.write_bytes(data)
def get_bytes(self, key: str) -> bytes:
return self._readable_path(key).read_bytes()
def iter_bytes(self, key: str, *, chunk_size: int = 1024 * 1024) -> Iterable[bytes]:
path = self._readable_path(key)
with path.open("rb") as handle:
while True:
chunk = handle.read(chunk_size)
if not chunk:
break
yield chunk
def delete(self, key: str) -> None:
path = self._path(key)
if path.exists() and path.is_file():
path.unlink()
def exists(self, key: str) -> bool:
try:
self._readable_path(key)
except StorageBackendError:
return False
return True
def stat(self, key: str) -> StorageObjectInfo:
path = self._readable_path(key)
return StorageObjectInfo(key=key, size_bytes=path.stat().st_size)
def list_objects(
self,
*,
prefix: str,
after: str | None = None,
limit: int = 500,
) -> StorageObjectPage:
normalized_limit = max(1, min(int(limit), 5000))
candidates: list[StorageObjectInfo] = []
for path in _iter_local_files(self.root):
key = path.relative_to(self.root).as_posix()
if not key.startswith(prefix) or (after is not None and key <= after):
continue
candidates.append(StorageObjectInfo(key=key, size_bytes=path.stat().st_size))
if len(candidates) > normalized_limit:
break
has_more = len(candidates) > normalized_limit
page = tuple(candidates[:normalized_limit])
return StorageObjectPage(
objects=page,
next_cursor=page[-1].key if has_more and page else None,
)
@dataclass(slots=True)
class S3StorageBackend:
bucket: str
endpoint_url: str
region_name: str
access_key_id: str
secret_access_key: str
deployment_managed: bool = False
name: str = "s3"
@property
def client(self):
if self.deployment_managed:
endpoint_url = _deployment_managed_garage_endpoint(self.endpoint_url)
else:
try:
endpoint_url = validate_unpinned_sdk_http_url(
self.endpoint_url,
label="File storage S3 endpoint",
)
except OutboundHttpError as exc:
raise StorageBackendError(str(exc)) from exc
try:
import boto3
from botocore.config import Config
except ModuleNotFoundError as exc:
raise StorageBackendError("boto3 is required for the S3 storage backend") from exc
options: dict[str, object] = {
"endpoint_url": endpoint_url,
"region_name": self.region_name,
"aws_access_key_id": self.access_key_id,
"aws_secret_access_key": self.secret_access_key,
}
if self.deployment_managed:
options["config"] = Config(s3={"addressing_style": "path"})
return boto3.client("s3", **options)
def put_bytes(self, key: str, data: bytes, *, content_type: str | None = None) -> None:
max_bytes = response_limit("file")
if len(data) > max_bytes:
raise StorageBackendError(f"Stored object exceeds the deployment limit of {max_bytes} bytes")
kwargs = {"Bucket": self.bucket, "Key": key, "Body": data}
if content_type:
kwargs["ContentType"] = content_type
self.client.put_object(**kwargs)
def get_bytes(self, key: str) -> bytes:
try:
obj = self.client.get_object(Bucket=self.bucket, Key=key)
max_bytes = response_limit("file")
body = obj["Body"]
try:
_reject_declared_object_size(obj, max_bytes=max_bytes)
data = body.read(max_bytes + 1)
if len(data) > max_bytes:
raise StorageBackendError(f"Stored object exceeds the deployment limit of {max_bytes} bytes")
return data
finally:
if hasattr(body, "close"):
body.close()
except Exception as exc: # pragma: no cover - depends on S3 backend
raise StorageBackendError(str(exc)) from exc
def iter_bytes(self, key: str, *, chunk_size: int = 1024 * 1024) -> Iterable[bytes]:
try:
obj = self.client.get_object(Bucket=self.bucket, Key=key)
max_bytes = response_limit("file")
body = obj["Body"]
try:
_reject_declared_object_size(obj, max_bytes=max_bytes)
total = 0
while True:
chunk = body.read(chunk_size)
if not chunk:
break
total += len(chunk)
if total > max_bytes:
raise StorageBackendError(f"Stored object exceeds the deployment limit of {max_bytes} bytes")
yield chunk
finally:
if hasattr(body, "close"):
body.close()
except Exception as exc: # pragma: no cover - depends on S3 backend
raise StorageBackendError(str(exc)) from exc
def delete(self, key: str) -> None:
self.client.delete_object(Bucket=self.bucket, Key=key)
def exists(self, key: str) -> bool:
try:
self.client.head_object(Bucket=self.bucket, Key=key)
return True
except Exception:
return False
def stat(self, key: str) -> StorageObjectInfo:
try:
response = self.client.head_object(Bucket=self.bucket, Key=key)
except Exception as exc: # pragma: no cover - depends on S3 backend
if _s3_missing_error(exc):
raise StorageObjectMissing("Stored object does not exist") from exc
raise StorageBackendError(str(exc)) from exc
try:
size = int(response.get("ContentLength"))
except (AttributeError, TypeError, ValueError) as exc:
raise StorageBackendError("S3 object metadata did not include a valid size") from exc
return StorageObjectInfo(key=key, size_bytes=size)
def list_objects(
self,
*,
prefix: str,
after: str | None = None,
limit: int = 500,
) -> StorageObjectPage:
normalized_limit = max(1, min(int(limit), 1000))
kwargs: dict[str, object] = {
"Bucket": self.bucket,
"Prefix": prefix,
"MaxKeys": normalized_limit,
}
if after:
kwargs["StartAfter"] = after
try:
response = self.client.list_objects_v2(**kwargs)
except Exception as exc: # pragma: no cover - depends on S3 backend
raise StorageBackendError(str(exc)) from exc
objects = tuple(
StorageObjectInfo(
key=str(item["Key"]),
size_bytes=int(item.get("Size") or 0),
)
for item in response.get("Contents", ())
if isinstance(item, dict) and item.get("Key")
)
has_more = bool(response.get("IsTruncated"))
return StorageObjectPage(
objects=objects,
next_cursor=objects[-1].key if has_more and objects else None,
)
def _reject_declared_object_size(obj: object, *, max_bytes: int) -> None:
if not isinstance(obj, dict):
return
try:
declared_size = int(obj.get("ContentLength"))
except (TypeError, ValueError):
return
if declared_size > max_bytes:
raise StorageBackendError(f"Stored object exceeds the deployment limit of {max_bytes} bytes")
def _iter_local_files(root: Path):
for entry in sorted(root.iterdir(), key=lambda item: item.name):
if entry.is_dir():
yield from _iter_local_files(entry)
elif entry.is_file():
yield entry
def _s3_missing_error(exc: Exception) -> bool:
response = getattr(exc, "response", None)
if not isinstance(response, dict):
return False
error = response.get("Error")
metadata = response.get("ResponseMetadata")
code = str(error.get("Code") if isinstance(error, dict) else "")
status_code = metadata.get("HTTPStatusCode") if isinstance(metadata, dict) else None
return code in {"404", "NoSuchKey", "NotFound"} or status_code == 404
def _deployment_managed_garage_endpoint(value: str) -> str:
endpoint = str(value or "").strip()
if endpoint != "http://garage:3900":
raise StorageBackendError(
"Deployment-managed S3 trust is restricted to http://garage:3900"
)
return endpoint
def _fallback_roots() -> tuple[Path, ...]:
raw = getattr(settings, "file_storage_local_fallback_roots", "") or ""
return tuple(Path(item.strip()) for item in str(raw).split(",") if item.strip())
def get_storage_backend() -> StorageBackend:
backend = settings.file_storage_backend.lower().strip()
if backend in {"local", "filesystem", "fs"}:
return LocalFilesystemStorageBackend(Path(settings.file_storage_local_root), fallback_roots=_fallback_roots())
if backend in {"s3", "garage"}:
return S3StorageBackend(
bucket=settings.file_storage_s3_bucket or settings.s3_bucket,
endpoint_url=settings.file_storage_s3_endpoint_url or settings.s3_endpoint_url,
region_name=settings.file_storage_s3_region or settings.s3_region,
access_key_id=settings.file_storage_s3_access_key_id or settings.s3_access_key_id,
secret_access_key=settings.file_storage_s3_secret_access_key or settings.s3_secret_access_key,
deployment_managed=bool(
getattr(
settings,
"file_storage_s3_deployment_managed",
False,
)
),
)
raise StorageBackendError(f"Unsupported file storage backend: {settings.file_storage_backend}")
"""Return the deployment-owned backend for Files-managed objects."""
return configured_storage_backend(settings)
__all__ = [
"LocalFilesystemStorageBackend",
"S3StorageBackend",
"StorageBackend",
"StorageBackendError",
"StorageObjectInfo",
"StorageObjectMissing",
"StorageObjectPage",
"get_storage_backend",
]