feat: implement Auth endpoints for web dashboard

decnet/web/api.py

@@ -0,0 +1,78 @@
+import uuid
+from contextlib import asynccontextmanager
+from datetime import timedelta
+from typing import Any, AsyncGenerator
+
+from fastapi import FastAPI, HTTPException, status
+from fastapi.middleware.cors import CORSMiddleware
+from pydantic import BaseModel
+
+from decnet.web.auth import (
+    ACCESS_TOKEN_EXPIRE_MINUTES,
+    create_access_token,
+    get_password_hash,
+    verify_password,
+)
+from decnet.web.sqlite_repository import SQLiteRepository
+
+repo: SQLiteRepository = SQLiteRepository()
+
+
+@asynccontextmanager
+async def lifespan(app: FastAPI) -> AsyncGenerator[None, None]:
+    await repo.initialize()
+    # Create default admin if no users exist
+    admin_user: dict[str, Any] | None = await repo.get_user_by_username("admin")
+    if not admin_user:
+        await repo.create_user(
+            {
+                "uuid": str(uuid.uuid4()),
+                "username": "admin",
+                "password_hash": get_password_hash("admin"),
+                "role": "admin",
+            }
+        )
+    yield
+
+
+app: FastAPI = FastAPI(
+    title="DECNET Web Dashboard API", 
+    version="1.0.0", 
+    lifespan=lifespan
+)
+
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+
+class Token(BaseModel):
+    access_token: str
+    token_type: str
+
+
+class LoginRequest(BaseModel):
+    username: str
+    password: str
+
+
+@app.post("/api/v1/auth/login", response_model=Token)
+async def login(request: LoginRequest) -> dict[str, str]:
+    user: dict[str, Any] | None = await repo.get_user_by_username(request.username)
+    if not user or not verify_password(request.password, user["password_hash"]):
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Incorrect username or password",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+
+    access_token_expires: timedelta = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
+    # Token uses uuid instead of sub
+    access_token: str = create_access_token(
+        data={"uuid": user["uuid"]}, expires_delta=access_token_expires
+    )
+    return {"access_token": access_token, "token_type": "bearer"}

decnet/web/auth.py

@@ -0,0 +1,33 @@
+import os
+from datetime import datetime, timedelta, timezone
+from typing import Optional, Any
+import jwt
+from passlib.context import CryptContext
+
+SECRET_KEY: str = os.environ.get("DECNET_SECRET_KEY", "super-secret-key-change-me")
+ALGORITHM: str = "HS256"
+ACCESS_TOKEN_EXPIRE_MINUTES: int = 1440
+
+pwd_context: CryptContext = CryptContext(schemes=["bcrypt"], deprecated="auto")
+
+
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    return pwd_context.verify(plain_password, hashed_password)
+
+
+def get_password_hash(password: str) -> str:
+    return pwd_context.hash(password)
+
+
+def create_access_token(data: dict[str, Any], expires_delta: Optional[timedelta] = None) -> str:
+    to_encode: dict[str, Any] = data.copy()
+    expire: datetime
+    if expires_delta:
+        expire = datetime.now(timezone.utc) + expires_delta
+    else:
+        expire = datetime.now(timezone.utc) + timedelta(minutes=15)
+        
+    to_encode.update({"exp": expire})
+    to_encode.update({"iat": datetime.now(timezone.utc)})
+    encoded_jwt: str = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
+    return encoded_jwt

tests/test_web_api.py

@@ -0,0 +1,47 @@
+import os
+from typing import Generator
+import pytest
+from fastapi.testclient import TestClient
+from decnet.web.api import app, repo
+
+
+@pytest.fixture(autouse=True)
+def setup_db() -> Generator[None, None, None]:
+    repo.db_path = "test_decnet.db"
+    if os.path.exists(repo.db_path):
+        os.remove(repo.db_path)
+    
+    # Yield control to the test function
+    yield
+    
+    # Teardown
+    if os.path.exists(repo.db_path):
+        os.remove(repo.db_path)
+
+
+def test_login_success() -> None:
+    with TestClient(app) as client:
+        # The TestClient context manager triggers startup/shutdown events
+        response = client.post(
+            "/api/v1/auth/login", 
+            json={"username": "admin", "password": "admin"}
+        )
+        assert response.status_code == 200
+        data = response.json()
+        assert "access_token" in data
+        assert data["token_type"] == "bearer"
+
+
+def test_login_failure() -> None:
+    with TestClient(app) as client:
+        response = client.post(
+            "/api/v1/auth/login", 
+            json={"username": "admin", "password": "wrongpassword"}
+        )
+        assert response.status_code == 401
+        
+        response = client.post(
+            "/api/v1/auth/login", 
+            json={"username": "nonexistent", "password": "wrongpassword"}
+        )
+        assert response.status_code == 401