from typing import Annotated

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


class User(BaseModel):
    username: str
    full_name: str | None = None


@app.put("/items/{item_id}")
async def update_item(

Jedes Event ist ein kleiner Textblock mit „Feldern“ wie `data`, `event`, `id` und `retry`, getrennt durch Leerzeilen.

Das sieht so aus:

```
data: {"name": "Portal Gun", "price": 999.99}

data: {"name": "Plumbus", "price": 32.99}

```

SSE wird häufig für KI-Chat-Streaming, Live-Benachrichtigungen, Logs und Observability sowie andere Fälle verwendet, in denen der Server Updates an den Client pusht.

/// tip | Tipp

Cada evento é um pequeno bloco de texto com “campos” como `data`, `event`, `id` e `retry`, separados por linhas em branco.

Fica assim:

```
data: {"name": "Portal Gun", "price": 999.99}

data: {"name": "Plumbus", "price": 32.99}

```

SSE é comumente usado para streaming de chat de IA, notificações em tempo real, logs e observabilidade, e outros casos em que o servidor envia atualizações para o cliente.

from fastapi import Body, FastAPI
from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


class User(BaseModel):
    username: str
    full_name: str | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item,
    user: User,

	// will set all product's price to last product's price + 10
	for idx, value := range []int64{410, 410, 410} {
		if products[idx].Price != value {
			t.Errorf("invalid price for product #%v, expects: %v, got %v", idx, value, products[idx].Price)
		}
	}

	products2 := []Product3{
		{Name: "Product-1", Price: 100},
		{Name: "Product-2", Price: 200},
		{Name: "Product-3", Price: 300},
	}

	DB.Create(&products2)

class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float = 10.5
    tags: list[str] = []


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}

class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Item = Body(
        examples=[
            {
                "name": "Foo",
                "description": "A very nice Item",
                "price": 35.4,
                "tax": 3.2,
            },
            {

    description: str | None = None
    price: float
    tax: float | None = None


@app.put("/items/{item_id}")
async def update_item(
    *,
    item_id: int,
    item: Annotated[
        Item,
        Body(
            examples=[
                {
                    "name": "Foo",
                    "description": "A very nice Item",
                    "price": 35.4,
                    "tax": 3.2,

from pydantic import BaseModel

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float


items = [
    Item(name="Plumbus", price=32.99),
    Item(name="Portal Gun", price=999.99),
    Item(name="Meeseeks Box", price=49.99),
]


@app.get("/items/stream", response_class=EventSourceResponse)
async def stream_items(

                        "required": ["name", "price"],
                        "type": "object",
                        "properties": {
                            "name": {"title": "Name", "type": "string"},
                            "description": {"title": "Description", "type": "string"},
                            "price": {"title": "Price", "type": "number"},
                        },
                    },