Basic CRUD

Use Case 1: Basic FastAPI CRUD API

Scenario: Create a simple user management API with CRUD operations.

Python

from fastapi import FastAPI, HTTPException
from contextlib import asynccontextmanager
from mongo_ops import (
    MongoConnectionManager,
    BaseDocument,
    BaseRepository,
    ModelRegistry
)
from pydantic import Field
from typing import Optional

# Define Model
class User(BaseDocument):
    username: str = Field(..., min_length=3, max_length=50)
    email: str = Field(...)
    is_active: bool = True

# Create Repository
class UserRepository(BaseRepository[User]):
    def __init__(self):
        super().__init__("users", User)

# Register Model
ModelRegistry.register("users", User, indexes=[("email", 1)])

# Setup FastAPI
@asynccontextmanager
async def lifespan(app: FastAPI):
    await MongoConnectionManager.connect(
        uri="mongodb://localhost:27017",
        db_name="myapp"
    )
    await ModelRegistry.initialize_all()
    yield
    await MongoConnectionManager.disconnect()

app = FastAPI(lifespan=lifespan)
user_repo = UserRepository()

# Endpoints
@app.post("/users/", response_model=User)
async def create_user(user: User):
    return await user_repo.create(user)

@app.get("/users/{user_id}", response_model=User)
async def get_user(user_id: str):
    user = await user_repo.get_by_id(user_id)
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    return user

@app.get("/users/", response_model=list[User])
async def list_users(skip: int = 0, limit: int = 10):
    return await user_repo.get_many(skip=skip, limit=limit)

@app.put("/users/{user_id}", response_model=User)
async def update_user(user_id: str, email: str):
    user = await user_repo.update(user_id, {"email": email})
    if not user:
        raise HTTPException(status_code=404, detail="User not found")
    return user

@app.delete("/users/{user_id}")
async def delete_user(user_id: str):
    deleted = await user_repo.delete(user_id)
    if not deleted:
        raise HTTPException(status_code=404, detail="User not found")
    return {"message": "User deleted successfully"}