video-accessibility/backend/app/core/authz.py
Vadym Samoilenko 31199f8705 chore: push all session changes — backend hardening, tests, apache config, deploy scripts
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-04-30 15:52:14 +01:00

236 lines
7.7 KiB
Python

"""
Central authorization module (Phase 3 SaaS).
Provides:
- MembershipContext — per-request resolved memberships dict
- get_membership_context — FastAPI dependency
- require_org_role(min_role) — dependency factory for org-scoped endpoints
- require_platform_admin — dependency for platform-only endpoints
- OrgScopedQuery — helper to add organization_id filter to MongoDB queries
"""
import json
from dataclasses import dataclass
from fastapi import Depends, HTTPException, status
from motor.motor_asyncio import AsyncIOMotorDatabase
from ..models.organization import OrgRole
from ..models.user import User, UserRole
from .database import get_database
from .dependencies import get_current_user
from .redis import get_redis
# Roles that see everything regardless of membership (kill-switch in comments)
# To restore old bypass: change STAFF_ROLES back to:
# {UserRole.ADMIN, UserRole.REVIEWER, UserRole.LINGUIST, UserRole.PRODUCTION}
PLATFORM_ADMIN_ROLES = {UserRole.ADMIN}
MEMBERSHIP_CACHE_TTL = 60 # seconds
@dataclass
class MembershipContext:
user: User
is_platform_admin: bool
# org_id → OrgRole mapping from the memberships collection
memberships: dict[str, OrgRole]
def can_access_org(self, org_id: str, min_role: OrgRole = OrgRole.VIEWER) -> bool:
if self.is_platform_admin:
return True
role = self.memberships.get(org_id)
return role is not None and role >= min_role
def accessible_org_ids(self) -> list[str]:
"""Return all org IDs the user has any membership in."""
return list(self.memberships.keys())
async def _load_memberships(user_id: str, db: AsyncIOMotorDatabase) -> dict[str, OrgRole]:
"""Load memberships from DB."""
result: dict[str, OrgRole] = {}
async for doc in db.memberships.find({"user_id": user_id}):
try:
result[doc["organization_id"]] = OrgRole(doc["role_in_org"])
except ValueError:
pass
return result
async def _cached_memberships(
user_id: str,
db: AsyncIOMotorDatabase,
) -> dict[str, OrgRole]:
"""Load memberships, with Redis cache (60s TTL)."""
cache_key = f"mem:user:{user_id}"
try:
redis = get_redis()
if redis:
cached = await redis.get(cache_key)
if cached:
raw = json.loads(cached)
return {org_id: OrgRole(role) for org_id, role in raw.items()}
except Exception:
pass
memberships = await _load_memberships(user_id, db)
try:
redis = get_redis()
if redis:
await redis.setex(
cache_key,
MEMBERSHIP_CACHE_TTL,
json.dumps({k: v.value for k, v in memberships.items()}),
)
except Exception:
pass
return memberships
async def get_membership_context(
current_user: User = Depends(get_current_user),
db: AsyncIOMotorDatabase = Depends(get_database),
) -> MembershipContext:
is_platform_admin = current_user.role in PLATFORM_ADMIN_ROLES
if is_platform_admin:
return MembershipContext(
user=current_user,
is_platform_admin=True,
memberships={},
)
memberships = await _cached_memberships(str(current_user.id), db)
return MembershipContext(
user=current_user,
is_platform_admin=False,
memberships=memberships,
)
def require_org_role(min_role: OrgRole):
"""
Dependency factory: ensures the current user has at least `min_role` in the
organization identified by the `org_id` path parameter.
Platform admins always pass.
"""
async def checker(
org_id: str,
ctx: MembershipContext = Depends(get_membership_context),
) -> MembershipContext:
if not ctx.can_access_org(org_id, min_role):
raise HTTPException(
status_code=status.HTTP_403_FORBIDDEN,
detail=f"Requires {min_role.value} role in this organization",
)
return ctx
return checker
def require_platform_admin():
"""Dependency: platform admin only."""
async def checker(ctx: MembershipContext = Depends(get_membership_context)) -> MembershipContext:
if not ctx.is_platform_admin:
raise HTTPException(status_code=status.HTTP_403_FORBIDDEN, detail="Platform admin required")
return ctx
return checker
class OrgScopedQuery:
"""
Helper that adds organization_id filters to MongoDB queries.
Usage:
scoped = OrgScopedQuery(ctx)
query = scoped.filter({"status": "completed"}, org_id_from_request)
If the user is a platform admin, the query is returned unchanged.
If a specific org_id is given, it's validated against the user's memberships.
If no org_id is given, the query is scoped to all orgs the user belongs to.
"""
def __init__(self, ctx: MembershipContext):
self.ctx = ctx
def filter(
self,
base_query: dict,
org_id: str | None = None,
org_field: str = "organization_id",
) -> dict:
if self.ctx.is_platform_admin:
if org_id:
return {**base_query, org_field: org_id}
return base_query
if org_id:
if not self.ctx.can_access_org(org_id):
raise HTTPException(
status_code=status.HTTP_403_FORBIDDEN,
detail="Access to this organization is not permitted",
)
return {**base_query, org_field: org_id}
accessible = self.ctx.accessible_org_ids()
if not accessible:
# User has no memberships — return an impossible query
return {**base_query, org_field: {"$in": []}}
return {**base_query, org_field: {"$in": accessible}}
def assert_user_in_org(
ctx: "MembershipContext",
org_id: str,
min_role: OrgRole = OrgRole.VIEWER,
) -> None:
"""Raise 403 if ctx user does not have min_role in org_id. Platform admins always pass."""
if not ctx.can_access_org(org_id, min_role):
raise HTTPException(
status_code=status.HTTP_403_FORBIDDEN,
detail="Access to this organization is not permitted",
)
async def get_job_or_403(
job_id: str,
ctx: "MembershipContext",
db: AsyncIOMotorDatabase,
) -> dict:
"""Load job document and verify ctx user can access its organization. Returns 404 for missing jobs."""
job_doc = await db.jobs.find_one({"_id": job_id})
if not job_doc:
raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Job not found")
org_id = job_doc.get("organization_id")
if not org_id:
# Legacy job without org: try resolving via project
project_id = job_doc.get("project_id")
if project_id:
project = await db.projects.find_one({"_id": project_id}, {"client_id": 1})
if project:
org_id = project.get("client_id")
if org_id:
if not ctx.can_access_org(org_id):
# Return 404 to avoid leaking existence of cross-org jobs
raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Job not found")
else:
# Truly legacy job (no project, no org): only the original uploader or admin can access
if not ctx.is_platform_admin and job_doc.get("client_id") != str(ctx.user.id):
raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Job not found")
return job_doc
async def bump_user_membership_cache(user_id: str) -> None:
"""Invalidate the Redis membership cache for a user (call on any membership write)."""
try:
redis = get_redis()
if redis:
await redis.delete(f"mem:user:{user_id}")
except Exception:
pass