## Example { #example }

Here's an example *path operation* with parameters using some of the above types.

{* ../../docs_src/extra_data_types/tutorial001_an_py310.py hl[1,3,12:16] *}

Note that the parameters inside the function have their natural data type, and you can, for example, perform normal date manipulations, like:

			Optional:    true,
		},
		HelpKV{
			Key:         Comment,
			Type:        "sentence",
			Description: DefaultComment,
			Optional:    true,
		},
	}
)

// DefaultHelpPostfix - Helper function to add (default: $value) messages in config help
func DefaultHelpPostfix(subsystem KVS, key string) string {
	val, found := subsystem.Lookup(key)
	if !found || val == "" {
		return ""
	}

package target

import (
	"sync"
	"sync/atomic"
)

// Inspired from Golang sync.Once but it is only marked
// initialized when the provided function returns nil.

type lazyInit struct {
	done uint32
	m    sync.Mutex
}

func (l *lazyInit) Do(f func() error) error {
	if atomic.LoadUint32(&l.done) == 0 {
		return l.doSlow(f)
	}
	return nil
}

from functools import lru_cache
from typing import Annotated

from fastapi import Depends, FastAPI

from .config import Settings

app = FastAPI()


@lru_cache
def get_settings():
    return Settings()


@app.get("/info")
async def info(settings: Annotated[Settings, Depends(get_settings)]):
    return {
        "app_name": settings.app_name,
        "admin_email": settings.admin_email,

For example, if you need to store it in a database.

For that, **FastAPI** provides a `jsonable_encoder()` function.

## Using the `jsonable_encoder` { #using-the-jsonable-encoder }

Let's imagine that you have a database `fake_db` that only receives JSON compatible data.

 */
package org.apache.maven.cling.invoker.mvn;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Objects;
import java.util.Optional;
import java.util.function.UnaryOperator;

import org.apache.maven.api.cli.mvn.MavenOptions;
import org.apache.maven.cling.invoker.LayeredOptions;

/**
 * Options that are "layered" by precedence order.
 *

`Cookie` es una clase "hermana" de `Path` y `Query`. También hereda de la misma clase común `Param`.

Pero recuerda que cuando importas `Query`, `Path`, `Cookie` y otros desde `fastapi`, en realidad son funciones que devuelven clases especiales.

///

/// info | Información

Para declarar cookies, necesitas usar `Cookie`, porque de lo contrario los parámetros serían interpretados como parámetros de query.

///

    "price": 42.0,
    "tax": 3.2
}
```

## Pour résumer

Vous pouvez ajouter plusieurs paramètres body dans votre fonction de routage, même si une requête ne peut avoir qu'un seul body.

Cependant, **FastAPI** se chargera de faire opérer sa magie, afin de toujours fournir à votre fonction des données correctes, les validera et documentera le schéma associé.

import functools

import pytest
from fastapi import (
    APIRouter,
    Depends,
    FastAPI,
    Header,
    WebSocket,
    WebSocketDisconnect,
    status,
)
from fastapi.middleware import Middleware
from fastapi.testclient import TestClient

router = APIRouter()
prefix_router = APIRouter()
native_prefix_route = APIRouter(prefix="/native")
app = FastAPI()


@app.websocket_route("/")

//     it defaults to defaultMaxSize.
//   - ttl: The time-to-live duration for each cache entry. If the provided ttl is less than or equal to 0,
//     it defaults to defaultTTL.
//
// This function defines an onEvicted callback that is invoked when a cache entry is evicted.
// The callback ensures that if the evicted value (v) is not nil, its Close method is called asynchronously
// to release associated resources.
//