feat: 1-to-1 message render + web data-lake backend

backend/src/api/routers/avatars.py

@@ -0,0 +1,40 @@
+from typing import Annotated
+
+import asyncpg
+from dishka.integrations.fastapi import DishkaRoute, FromDishka
+from fastapi import APIRouter, HTTPException, Query
+from fastapi.responses import FileResponse
+
+from utils.jobs import enqueue
+from utils.read.avatars import current_avatar
+from utils.storage import ContentAddressedStorage
+
+router = APIRouter(prefix="/api/avatars", tags=["avatars"], route_class=DishkaRoute)
+
+
+@router.get("/{owner_kind}/{owner_id}")
+async def serve_avatar(
+    pool: FromDishka[asyncpg.Pool],
+    storage: FromDishka[ContentAddressedStorage],
+    owner_kind: str,
+    owner_id: int,
+    account_id: Annotated[int, Query()],
+) -> FileResponse:
+    avatar = await current_avatar(pool, account_id, owner_kind, owner_id)
+    if avatar is None:
+        raise HTTPException(status_code=404, detail="avatar not found")
+    if not avatar.downloaded or avatar.storage_key is None:
+        await enqueue(
+            pool,
+            account_id,
+            "fetch_avatar",
+            {
+                "owner_kind": owner_kind,
+                "owner_id": owner_id,
+                "unique_id": avatar.unique_id,
+            },
+        )
+        raise HTTPException(status_code=409, detail="avatar not downloaded; fetching")
+    return FileResponse(
+        storage.url(avatar.storage_key), media_type=avatar.mime or "image/jpeg"
+    )