from fastapi import FastAPI, HTTPException

app = FastAPI()

items = {"foo": "The Foo Wrestlers"}


@app.get("/items-header/{item_id}")
async def read_item_header(item_id: str):
    if item_id not in items:
        raise HTTPException(
            status_code=404,
            detail="Item not found",
            headers={"X-Error": "There goes my error"},
        )

///

## Tags

You can add tags to your *path operation*, pass the parameter `tags` with a `list` of `str` (commonly just one `str`):

//// tab | Python 3.10+

```Python hl_lines="15  20  25"
{!> ../../docs_src/path_operation_configuration/tutorial002_py310.py!}
```

////

//// tab | Python 3.9+

```Python hl_lines="6-7"
{!../../docs_src/query_params/tutorial005.py!}
```

Hier ist `needy` ein erforderlicher Query-Parameter vom Typ `str`.

Wenn Sie in Ihrem Browser eine URL wie:

```
http://127.0.0.1:8000/items/foo-item
```

... öffnen, ohne den benötigten Parameter `needy`, dann erhalten Sie einen Fehler wie den folgenden:

from fastapi.testclient import TestClient
from pydantic import BaseModel, ConfigDict, Field

app = FastAPI()


class Model(BaseModel):
    name: str = Field(alias="alias")


class ModelNoAlias(BaseModel):
    name: str

    if PYDANTIC_V2:
        model_config = ConfigDict(
            json_schema_extra={
                "description": (

from fastapi import FastAPI, Response, status

app = FastAPI()

tasks = {"foo": "Listen to the Bar Fighters"}


@app.put("/get-or-create-task/{task_id}", status_code=200)
def get_or_create_task(task_id: str, response: Response):
    if task_id not in tasks:
        tasks[task_id] = "This didn't exist before"
        response.status_code = status.HTTP_201_CREATED

from datetime import datetime

from fastapi import FastAPI
from pydantic import BaseModel

app = FastAPI()


class Subscription(BaseModel):
    username: str
    monthly_fee: float
    start_date: datetime


@app.webhooks.post("new-subscription")
def new_subscription(body: Subscription):
    """
    When a new user subscribes to your service we'll send you a POST request with this

from fastapi import Depends, FastAPI

app = FastAPI()


async def common_parameters(q: str | None = None, skip: int = 0, limit: int = 100):
    return {"q": q, "skip": skip, "limit": limit}


@app.get("/items/")
async def read_items(commons: dict = Depends(common_parameters)):
    return commons


@app.get("/users/")
async def read_users(commons: dict = Depends(common_parameters)):

	args   []string // Formal arguments.
	tokens []Token  // Body of macro.
}

// Tokenize turns a string into a list of Tokens; used to parse the -D flag and in tests.
func Tokenize(str string) []Token {
	t := NewTokenizer("command line", strings.NewReader(str), nil)
	var tokens []Token
	for {
		tok := t.Next()
		if tok == scanner.EOF {
			break
		}
		tokens = append(tokens, Make(tok, t.Text()))
	}
	return tokens

from docs_src.custom_response.tutorial008 import app

client = TestClient(app)


def test_get(tmp_path: Path):
    file_path: Path = tmp_path / "large-video-file.mp4"
    tutorial008.some_file_path = str(file_path)
    test_content = b"Fake video bytes"
    file_path.write_bytes(test_content)
    response = client.get("/")

from fastapi import FastAPI, Path, Query

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    item_id: Annotated[int, Path(title="The ID of the item to get")],
    q: Annotated[Union[str, None], Query(alias="item-query")] = None,
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})