api.py

from fastapi import FastAPI, HTTPException
from pydantic import BaseModel
from typing import Optional, List
import uvicorn

# Initialize FastAPI app
app = FastAPI(
    title="My API Service",
    description="A sample REST API service with Swagger documentation",
    version="1.0.0"
)

# Data models
class Item(BaseModel):
    id: Optional[int] = None
    name: str
    description: Optional[str] = None
    price: float
    in_stock: bool = True

class User(BaseModel):
    id: Optional[int] = None
    username: str
    email: str
    full_name: Optional[str] = None

# In-memory storage
items_db = []
users_db = []
item_id_counter = 1
user_id_counter = 1

# Root endpoint
@app.get("/")
async def root():
    """Welcome endpoint"""
    return {"message": "Welcome to the API. Visit /docs for Swagger UI"}

# Item endpoints
@app.post("/items/", response_model=Item, tags=["items"])
async def create_item(item: Item):
    """Create a new item"""
    global item_id_counter
    item.id = item_id_counter
    item_id_counter += 1
    items_db.append(item)
    return item

@app.get("/items/", response_model=List[Item], tags=["items"])
async def get_items():
    """Get all items"""
    return items_db

@app.get("/items/{item_id}", response_model=Item, tags=["items"])
async def get_item(item_id: int):
    """Get a specific item by ID"""
    for item in items_db:
        if item.id == item_id:
            return item
    raise HTTPException(status_code=404, detail="Item not found")

@app.put("/items/{item_id}", response_model=Item, tags=["items"])
async def update_item(item_id: int, item: Item):
    """Update an existing item"""
    for idx, existing_item in enumerate(items_db):
        if existing_item.id == item_id:
            item.id = item_id
            items_db[idx] = item
            return item
    raise HTTPException(status_code=404, detail="Item not found")

@app.delete("/items/{item_id}", tags=["items"])
async def delete_item(item_id: int):
    """Delete an item"""
    for idx, item in enumerate(items_db):
        if item.id == item_id:
            items_db.pop(idx)
            return {"message": "Item deleted successfully"}
    raise HTTPException(status_code=404, detail="Item not found")

# User endpoints
@app.post("/users/", response_model=User, tags=["users"])
async def create_user(user: User):
    """Create a new user"""
    global user_id_counter
    user.id = user_id_counter
    user_id_counter += 1
    users_db.append(user)
    return user

@app.get("/users/", response_model=List[User], tags=["users"])
async def get_users():
    """Get all users"""
    return users_db

@app.get("/users/{user_id}", response_model=User, tags=["users"])
async def get_user(user_id: int):
    """Get a specific user by ID"""
    for user in users_db:
        if user.id == user_id:
            return user
    raise HTTPException(status_code=404, detail="User not found")

# Health check endpoint
@app.get("/health", tags=["system"])
async def health_check():
    """Check if the service is running"""
    return {"status": "healthy", "service": "running"}

if __name__ == "__main__":
    # Run the service
    uvicorn.run(app, host="0.0.0.0", port=8000)