add authentication

app/server.py

@@ -5,6 +5,8 @@
 from hydra import compose, initialize
 from langserve import add_routes
 
+from backend import USE_AUTHENTICATION
+from backend.api_plugins import authentication_routes, session_routes
 from backend.rag_1.chain import get_chain as get_chain_rag_1
 from backend.rag_1.config import validate_config as validate_config_1
 from backend.rag_2.chain import get_chain as get_chain_rag_2
@@ -42,15 +44,21 @@ async def redirect_root_to_docs() -> RedirectResponse:
     # validate config
     _ = validate_config_3(config_3)
 
+if USE_AUTHENTICATION:
+    auth = authentication_routes(app)
+    session_routes(app, authentication=auth)
+    dependencies = [auth]
+else:
+    dependencies = None
 
 chain_rag_1 = get_chain_rag_1(config_1)
-add_routes(app, chain_rag_1, path="/rag-1")
+add_routes(app, chain_rag_1, path="/rag-1", dependencies=dependencies)
 
 chain_rag_2 = get_chain_rag_2(config_2)
-add_routes(app, chain_rag_2, path="/rag-2")
+add_routes(app, chain_rag_2, path="/rag-2", dependencies=dependencies)
 
 chain_rag_3 = get_chain_rag_3(config_3)
-add_routes(app, chain_rag_3, path="/rag-3")
+add_routes(app, chain_rag_3, path="/rag-3", dependencies=dependencies)
 
 if __name__ == "__main__":
     import uvicorn

backend/__init__.py

@@ -1 +1,18 @@
 """Backend operations of RAG."""
+
+import os
+
+from dotenv import load_dotenv
+
+load_dotenv()
+
+DATABASE_URL = os.getenv("DATABASE_URL")
+
+# Private key used to generate the JWT tokens for secure authentication
+SECRET_KEY = os.getenv("SECRET_KEY", "default_unsecure_key")
+
+# Algorithm used to generate JWT tokens
+ALGORITHM = os.getenv("ALGORITHM", "HS256")
+
+# Activate or deactivate the secure authentication
+USE_AUTHENTICATION = bool(int(os.getenv("USE_AUTHENTICATION", True)))

backend/api_plugins/secure_authentication/secure_authentication.py

@@ -0,0 +1,106 @@
+from pathlib import Path
+
+from fastapi import Depends, HTTPException, Response, status
+from fastapi.security import OAuth2PasswordBearer, OAuth2PasswordRequestForm
+from jose import JWTError, jwt
+
+from backend import ADMIN_MODE
+from backend.api_plugins.lib.user_management import (
+    ALGORITHM,
+    SECRET_KEY,
+    UnsecureUser,
+    User,
+    authenticate_user,
+    create_access_token,
+    create_user,
+    delete_user,
+    get_user,
+    user_exists,
+)
+
+
+def authentication_routes(app, dependencies=list[Depends]):
+    from backend.database import Database
+
+    with Database() as connection:
+        connection.run_script(Path(__file__).parent / "users_tables.sql")
+
+    oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/user/login")
+
+    async def get_current_user(token: str = Depends(oauth2_scheme)) -> User:
+        credentials_exception = HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Could not validate credentials",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+        try:
+            payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
+            email: str = payload.get("email")
+            if email is None:
+                raise credentials_exception
+
+            user = get_user(email)
+            if user is None:
+                raise credentials_exception
+            return user
+        except JWTError:
+            raise credentials_exception
+
+    @app.post("/user/signup", include_in_schema=ADMIN_MODE)
+    async def signup(user: UnsecureUser) -> dict:
+        if not ADMIN_MODE:
+            raise HTTPException(
+                status_code=status.HTTP_403_FORBIDDEN, detail="Signup is disabled"
+            )
+
+        user = User.from_unsecure_user(user)
+        if user_exists(user.email):
+            raise HTTPException(
+                status_code=status.HTTP_400_BAD_REQUEST,
+                detail=f"User {user.email} already registered",
+            )
+
+        create_user(user)
+        return {"email": user.email}
+
+    @app.delete("/user/")
+    async def del_user(current_user: User = Depends(get_current_user)) -> dict:
+        email = current_user.email
+        try:
+            user = get_user(email)
+            if user is None:
+                raise HTTPException(
+                    status_code=status.HTTP_404_NOT_FOUND,
+                    detail=f"User {email} not found",
+                )
+            delete_user(email)
+            return {"detail": f"User {email} deleted"}
+        except Exception:
+            raise HTTPException(
+                status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
+                detail="Internal Server Error",
+            )
+
+    @app.post("/user/login")
+    async def login(form_data: OAuth2PasswordRequestForm = Depends()) -> dict:
+        user = authenticate_user(form_data.username, form_data.password)
+        if not user:
+            raise HTTPException(
+                status_code=status.HTTP_401_UNAUTHORIZED,
+                detail="Incorrect username or password",
+                headers={"WWW-Authenticate": "Bearer"},
+            )
+        user_data = user.dict()
+        del user_data["hashed_password"]
+        access_token = create_access_token(data=user_data)
+        return {"access_token": access_token, "token_type": "bearer"}
+
+    @app.get("/user/me")
+    async def user_me(current_user: User = Depends(get_current_user)) -> User:
+        return current_user
+
+    @app.get("/user")
+    async def user_root() -> dict:
+        return Response("User management routes are enabled.", status_code=200)
+
+    return Depends(get_current_user)

backend/api_plugins/secure_authentication/users_tables.sql

@@ -0,0 +1,7 @@
+-- Dialect MUST be sqlite, even if the database you use is different.
+-- It is transpiled to the right dialect when executed.
+
+CREATE TABLE IF NOT EXISTS "users" (
+    "email" VARCHAR(255) PRIMARY KEY,
+    "password" TEXT
+);

backend/api_plugins/sessions/sessions.py

@@ -0,0 +1,82 @@
+import json
+from collections.abc import Sequence
+from datetime import datetime
+from pathlib import Path
+from uuid import uuid4
+
+from fastapi import APIRouter, Depends, FastAPI, Response
+
+from backend.api_plugins.lib.user_management import User
+
+
+def session_routes(
+    app: FastAPI | APIRouter,
+    *,
+    authentication: Depends = None,
+    dependencies: Sequence[Depends] | None = None,
+):
+    from backend.database import Database
+    from backend.model import Message
+
+    with Database() as connection:
+        connection.run_script(Path(__file__).parent / "sessions_tables.sql")
+
+    @app.post("/session/new")
+    async def chat_new(
+        current_user: User = authentication, dependencies=dependencies
+    ) -> dict:
+        chat_id = str(uuid4())
+        timestamp = datetime.utcnow().isoformat()
+        user_id = current_user.email if current_user else "unauthenticated"
+        with Database() as connection:
+            connection.execute(
+                "INSERT INTO session (id, timestamp, user_id) VALUES (?, ?, ?)",
+                (chat_id, timestamp, user_id),
+            )
+        return {"session_id": chat_id}
+
+    @app.get("/session/list")
+    async def chat_list(
+        current_user: User = authentication, dependencies=dependencies
+    ) -> list[dict]:
+        user_email = current_user.email if current_user else "unauthenticated"
+        chats = []
+        with Database() as connection:
+            result = connection.execute(
+                "SELECT id, timestamp FROM session WHERE user_id = ? ORDER BY timestamp DESC",
+                (user_email,),
+            )
+            chats = [{"id": row[0], "timestamp": row[1]} for row in result]
+        return chats
+
+    @app.get("/session/{session_id}")
+    async def chat(
+        session_id: str, current_user: User = authentication, dependencies=dependencies
+    ) -> dict:
+        messages: list[Message] = []
+        with Database() as connection:
+            result = connection.execute(
+                "SELECT id, timestamp, session_id, message FROM message_history WHERE session_id = ? ORDER BY timestamp ASC",
+                (session_id,),
+            )
+            for row in result:
+                content = json.loads(row[3])["data"]["content"]
+                message_type = json.loads(row[3])["type"]
+                message = Message(
+                    id=row[0],
+                    timestamp=row[1],
+                    session_id=row[2],
+                    sender=message_type if message_type == "human" else "ai",
+                    content=content,
+                )
+                messages.append(message)
+        return {
+            "chat_id": session_id,
+            "messages": [message.dict() for message in messages],
+        }
+
+    @app.get("/session")
+    async def session_root(
+        current_user: User = authentication, dependencies=dependencies
+    ) -> dict:
+        return Response("Sessions management routes are enabled.", status_code=200)

backend/api_plugins/sessions/sessions_tables.sql

@@ -0,0 +1,9 @@
+-- Dialect MUST be sqlite, even if the database you use is different.
+-- It is transpiled to the right dialect when executed.
+
+CREATE TABLE IF NOT EXISTS "session" (
+    "id" VARCHAR(255) PRIMARY KEY,
+    "timestamp" DATETIME,
+    "user_id" VARCHAR(255),
+    FOREIGN KEY ("user_id") REFERENCES "users" ("email")
+);