### Sem tipo de retorno { #no-return-type }

Você também pode omitir o tipo de retorno. O FastAPI então usará o [`jsonable_encoder`](./encoder.md) para converter os dados em algo que possa ser serializado para JSON e depois enviá-los como JSON Lines.

{* ../../docs_src/stream_json_lines/tutorial001_py310.py ln[33:36] hl[34] *}

## Eventos enviados pelo servidor (SSE) { #server-sent-events-sse }

クライアントが**余分なヘッダー**を送信しようとすると、**エラー**レスポンスが返されます。

例えば、クライアントが値 `plumbus` の `tool` ヘッダーを送ろうとすると、ヘッダーパラメータ `tool` は許可されていない旨の**エラー**レスポンスが返されます:

```json
{
    "detail": [
        {
            "type": "extra_forbidden",
            "loc": ["header", "tool"],
            "msg": "Extra inputs are not permitted",
            "input": "plumbus",
        }
    ]
}
```

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"testing"
	"time"
)

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package cmd

import (
	"context"
	"errors"
	"fmt"

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package lifecycle

import (
	"encoding/xml"
	"time"

// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package scanner

import (
	"fmt"
	"strconv"
	"time"

    },
    "required": ["loc", "msg", "type"],
}

validation_error_response_definition = {
    "title": "HTTPValidationError",
    "type": "object",
    "properties": {
        "detail": {
            "title": "Detail",
            "type": "array",
            "items": {"$ref": REF_PREFIX + "ValidationError"},
        }
    },
}

status_code_ranges: dict[str, str] = {
    "1XX": "Information",

Yukarıdaki durumların herhangi birinde FastAPI yine de asenkron olarak çalışır ve son derece hızlıdır.

Ancak yukarıdaki adımları izleyerek bazı performans optimizasyonları mümkün olur.

## Teknik Detaylar { #technical-details }

Python’un modern sürümleri, **`async` ve `await`** sözdizimiyle, **"coroutines"** denilen bir yapıyı kullanarak **"asenkron kod"** desteğine sahiptir.

Aşağıdaki bölümlerde bu ifadeyi parça parça ele alalım:

                                                <tr
                                                        data-href="${contextPath}/admin/dict/kuromoji/details/${f:u(dictId)}/4/${f:u(data.id)}">
                                                    <td>${f:h(data.token)}</td>
                                                    <td>${f:h(data.reading)}</td>

 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */