feat: add API key auth dependency

pyproject.toml

@@ -53,7 +53,7 @@ extend-exclude = ["alembic", "tests"]
 select = ["E", "F", "I", "N", "UP", "B", "A", "SIM"]
 
 [tool.ruff.lint.flake8-bugbear]
-extend-immutable-calls = ["Depends", "fastapi.Depends", "Query", "fastapi.Query"]
+extend-immutable-calls = ["Depends", "fastapi.Depends", "Query", "fastapi.Query", "Security", "fastapi.Security"]
 
 [tool.mypy]
 plugins = ["pydantic.mypy"]

src/proxy_pool/accounts/auth.py

@@ -0,0 +1,29 @@
+from fastapi import Depends, HTTPException, Security, status
+from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from proxy_pool.accounts.models import User
+from proxy_pool.accounts.service import verify_api_key
+from proxy_pool.common.dependencies import get_db
+
+security = HTTPBearer()
+
+
+async def get_current_user(
+    credentials: HTTPAuthorizationCredentials = Security(security),
+    db: AsyncSession = Depends(get_db),
+) -> User:
+    """FastAPI dependency that resolves an API key to a User.
+
+    Usage in routes:
+        @router.get("/something")
+        async def something(user: User = Depends(get_current_user)):
+    """
+    user = await verify_api_key(db, credentials.credentials)
+    if user is None:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid or expired API key",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    return user