Refactor the API to use a sample in-memory User model

README.md

@@ -53,3 +53,14 @@ docker run -p 8000:8000 -it app
 - If you face an issue with **git ssh access** while pushing new changes, run `ssh-add $HOME/.ssh/<your ssh key>` in terminal outside the devcontainer.
 
 - If you face an issue during **devcontainer build**, make sure the repo is marked as trusted in VSCode. Check `Source Control` tab in the sidebar to mark the repo safe, then rebuild the devcontainer.
+
+## Sample CRUD API
+
+The `/v1` directory contains a sample API router demonstrating basic CRUD operations for users:
+
+- Endpoints: Create, Read, Update, Delete users
+- Router setup: `app/v1/routers/base.py` and `app/v1/routers/users.py`
+- User model: `app/v1/models/user.py`
+- User management: `app/v1/services/user/user_manager.py`
+
+Use the samples as a starting point for your own API endpoints. View available endpoints at `http://localhost:8000/docs`.

app/v1/models/__init__.py

@@ -0,0 +1,3 @@
+__all__ = ["User"]
+
+from app.v1.models.user import User

app/v1/models/user.py

@@ -0,0 +1,6 @@
+from pydantic import BaseModel, EmailStr
+
+
+class User(BaseModel):
+    username: str
+    email: EmailStr

app/v1/routers/base.py

@@ -1,7 +1,7 @@
 from fastapi import APIRouter
 
-from app.v1.routers.dummy import router as dummy_router
+from app.v1.routers.users import router as users_router
 
 
 router = APIRouter(prefix="/v1")
-router.include_router(dummy_router, prefix="/dummy", tags=["Dummy"])
+router.include_router(users_router, prefix="/users", tags=["Users"])

app/v1/routers/users.py

@@ -0,0 +1,44 @@
+from fastapi import APIRouter, Depends, HTTPException, status
+
+from app.v1.models import User
+from app.v1.services import UserManager, get_user_manager
+
+
+router = APIRouter()
+
+
+@router.post("/")
+async def create_user(user: User, user_manager: UserManager = Depends(get_user_manager)) -> User:
+    try:
+        return user_manager.create_user(user)
+    except ValueError as ex:
+        raise HTTPException(status_code=status.HTTP_409_CONFLICT, detail=str(ex))
+
+
+@router.get("/{username}")
+async def get_user(username: str, user_manager: UserManager = Depends(get_user_manager)) -> User:
+    try:
+        return user_manager.get_user(username)
+    except ValueError as ex:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(ex))
+
+
+@router.get("/")
+async def list_users(user_manager: UserManager = Depends(get_user_manager)) -> list[User]:
+    return user_manager.list_users()
+
+
+@router.put("/{username}")
+async def update_user(username: str, user: User, user_manager: UserManager = Depends(get_user_manager)) -> User:
+    try:
+        return user_manager.update_user(username, user)
+    except ValueError as ex:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(ex))
+
+
+@router.delete("/{username}")
+async def delete_user(username: str, user_manager: UserManager = Depends(get_user_manager)) -> User:
+    try:
+        return user_manager.delete_user(username)
+    except ValueError as ex:
+        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail=str(ex))

app/v1/services/__init__.py

@@ -0,0 +1,4 @@
+__all__ = ["get_user_manager", "UserManager"]
+
+from app.v1.services.user.dependency import get_user_manager
+from app.v1.services.user.user_manager import UserManager

app/v1/services/user/dependency.py

@@ -0,0 +1,5 @@
+from app.v1.services.user.user_manager import UserManager
+
+
+def get_user_manager() -> UserManager:
+    return UserManager()

app/v1/services/user/user_manager.py

@@ -0,0 +1,30 @@
+from app.v1.models import User
+
+
+class UserManager:
+    _users: dict[str, User] = {}
+
+    def create_user(self, user: User) -> User:
+        if user.username in self._users:
+            raise ValueError(f"User with username '{user.username}' already exists")
+        self._users[user.username] = user
+        return user
+
+    def get_user(self, username: str) -> User:
+        if username not in self._users:
+            raise ValueError(f"User with username '{username}' does not exist")
+        return self._users[username]
+
+    def list_users(self) -> list[User]:
+        return list(self._users.values())
+
+    def update_user(self, username: str, user: User) -> User:
+        if username not in self._users:
+            raise ValueError(f"User with username '{username}' does not exist")
+        self._users[username] = user
+        return user
+
+    def delete_user(self, username: str) -> User:
+        if username not in self._users:
+            raise ValueError(f"User with username '{username}' does not exist")
+        return self._users.pop(username)

tests/v1/routers/test_users.py

@@ -0,0 +1,86 @@
+from fastapi.testclient import TestClient
+
+
+def test_create_user(client: TestClient) -> None:
+    user_data = {"username": "testuser", "email": "[email protected]"}
+    response = client.post("/v1/users/", json=user_data)
+    assert response.status_code == 200
+    assert response.json() == user_data
+
+
+def test_get_user(client: TestClient) -> None:
+    # First, create a user
+    user_data = {"username": "getuser", "email": "[email protected]"}
+    client.post("/v1/users/", json=user_data)
+
+    # Then, retrieve the user
+    response = client.get("/v1/users/getuser")
+    assert response.status_code == 200
+    assert response.json() == user_data
+
+
+def test_list_users(client: TestClient) -> None:
+    # Create two users
+    user1 = {"username": "user1", "email": "[email protected]"}
+    user2 = {"username": "user2", "email": "[email protected]"}
+    client.post("/v1/users/", json=user1)
+    client.post("/v1/users/", json=user2)
+
+    # List all users
+    response = client.get("/v1/users/")
+    assert response.status_code == 200
+    assert len(response.json()) >= 2
+    assert user1 in response.json()
+    assert user2 in response.json()
+
+
+def test_update_user(client: TestClient) -> None:
+    # First, create a user
+    original_data = {"username": "updateuser", "email": "[email protected]"}
+    client.post("/v1/users/", json=original_data)
+
+    # Then, update the user
+    updated_data = {"username": "updateuser", "email": "[email protected]"}
+    response = client.put("/v1/users/updateuser", json=updated_data)
+    assert response.status_code == 200
+    assert response.json() == updated_data
+
+
+def test_delete_user(client: TestClient) -> None:
+    # First, create a user
+    user_data = {"username": "deleteuser", "email": "[email protected]"}
+    client.post("/v1/users/", json=user_data)
+
+    # Then, delete the user
+    response = client.delete("/v1/users/deleteuser")
+    assert response.status_code == 200
+    assert response.json() == user_data
+
+    # Verify the user is deleted
+    response = client.get("/v1/users/deleteuser")
+    assert response.status_code == 404
+
+
+def test_create_duplicate_user(client: TestClient) -> None:
+    user_data = {"username": "duplicate", "email": "[email protected]"}
+    client.post("/v1/users/", json=user_data)
+
+    # Try to create a user with the same username
+    response = client.post("/v1/users/", json=user_data)
+    assert response.status_code == 409
+
+
+def test_get_nonexistent_user(client: TestClient) -> None:
+    response = client.get("/v1/users/nonexistent")
+    assert response.status_code == 404
+
+
+def test_update_nonexistent_user(client: TestClient) -> None:
+    user_data = {"username": "nonexistent", "email": "[email protected]"}
+    response = client.put("/v1/users/nonexistent", json=user_data)
+    assert response.status_code == 404
+
+
+def test_delete_nonexistent_user(client: TestClient) -> None:
+    response = client.delete("/v1/users/nonexistent")
+    assert response.status_code == 404