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Response class

esmerald.Response 

Response(content, *, status_code=HTTP_200_OK, media_type=JSON, background=None, headers=None, cookies=None, encoders=None)

Bases: Response, Generic[T]

Default Response object from Esmerald where it can be as the return annotation of a handler.

Esmerakd automatically will understand what time of response is going to be used and parse all the details automatically.

Example

from pydantic import BaseModel

from esmerald import Esmerald, Gateway, Response, get
from esmerald.datastructures import Cookie


@get(path="/me")
async def home() -> Response:
    return Response(
        Item(id=1, sku="sku1238"),
        headers={"SKY-HEADER": "sku-xyz"},
        cookies=[Cookie(key="sku", value="a-value")],
    )


Esmerald(routes=[Gateway(handler=home)])
PARAMETER DESCRIPTION
content

Any content being sent to the response.

TYPE: Any

status_code

The response status code.

TYPE: int DEFAULT: HTTP_200_OK

media_type

The media type used in the response.

TYPE: Optional[Union[MediaType, str]] DEFAULT: JSON

background

Any instance of a BackgroundTask or BackgroundTasks.

TYPE: Optional[Union[BackgroundTask, BackgroundTasks]] DEFAULT: None

headers

Any additional headers being passed to the response.

TYPE: Optional[Dict[str, Any]] DEFAULT: None

cookies

A sequence of esmerald.datastructures.Cookie objects.

Read more about the Cookies.

Example

from esmerald import Response
from esmerald.datastructures import Cookie

response_cookies=[
    Cookie(
        key="csrf",
        value="CIwNZNlR4XbisJF39I8yWnWX9wX4WFoz",
        max_age=3000,
        httponly=True,
    )
]

Response(response_cookies=response_cookies)

TYPE: Optional[ResponseCookies] DEFAULT: None

encoders

A sequence of esmerald.encoders.Encoder type of objects to be used by the response object directly.

Example

from esmerald import Response
from esmerald.encoders import PydanticEncoder, MsgSpecEncoder

response_cookies=[
    encoders=[PydanticEncoder, MsgSpecEncoder]
]

Response(response_cookies=response_cookies)

TYPE: Union[Sequence[Encoder], None] DEFAULT: None

Source code in esmerald/responses/base.py 
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def __init__(
    self,
    content: Annotated[
        Any,
        Doc(
            """
            Any content being sent to the response.
            """
        ),
    ],
    *,
    status_code: Annotated[
        int,
        Doc(
            """
            The response status code.
            """
        ),
    ] = status.HTTP_200_OK,
    media_type: Annotated[
        Optional[Union[MediaType, str]],
        Doc(
            """
            The media type used in the response.
            """
        ),
    ] = MediaType.JSON,
    background: Annotated[
        Optional[Union["BackgroundTask", "BackgroundTasks"]],
        Doc(
            """
            Any instance of a [BackgroundTask or BackgroundTasks](https://esmerald.dev/background-tasks/).
            """
        ),
    ] = None,
    headers: Annotated[
        Optional[Dict[str, Any]],
        Doc(
            """
            Any additional headers being passed to the response.
            """
        ),
    ] = None,
    cookies: Annotated[
        Optional["ResponseCookies"],
        Doc(
            """
            A sequence of `esmerald.datastructures.Cookie` objects.

            Read more about the [Cookies](https://esmerald.dev/extras/cookie-fields/?h=responsecook#cookie-from-response-cookies).

            **Example**

            ```python
            from esmerald import Response
            from esmerald.datastructures import Cookie

            response_cookies=[
                Cookie(
                    key="csrf",
                    value="CIwNZNlR4XbisJF39I8yWnWX9wX4WFoz",
                    max_age=3000,
                    httponly=True,
                )
            ]

            Response(response_cookies=response_cookies)
            ```
            """
        ),
    ] = None,
    encoders: Annotated[
        Union[Sequence[Encoder], None],
        Doc(
            """
            A sequence of `esmerald.encoders.Encoder` type of objects to be used
            by the response object directly.

            **Example**

            ```python
            from esmerald import Response
            from esmerald.encoders import PydanticEncoder, MsgSpecEncoder

            response_cookies=[
                encoders=[PydanticEncoder, MsgSpecEncoder]
            ]

            Response(response_cookies=response_cookies)
            ```
            """
        ),
    ] = None,
) -> None:
    super().__init__(
        content=content,
        status_code=status_code,
        headers=headers or {},
        media_type=media_type,
        background=cast("BackgroundTask", background),
        encoders=encoders,
    )
    self.cookies = cookies or []

media_type class-attribute instance-attribute 

media_type = None

status_code class-attribute instance-attribute 

status_code = None

charset class-attribute instance-attribute 

charset = 'utf-8'

background instance-attribute 

background = background

encoders instance-attribute 

encoders = encoders or []

body instance-attribute 

body = make_response(content)

raw_headers instance-attribute 

raw_headers = []

headers property 

headers

encoded_headers property 

encoded_headers

cookies instance-attribute 

cookies = cookies or []

make_headers 

make_headers(content_headers=None)

Initializes the headers based on RFC specifications by setting appropriate conditions and restrictions.

PARAMETER DESCRIPTION
content_headers

TYPE: Mapping[str, str] | dict[str, str] | None DEFAULT: None

PARAMETER DESCRIPTION
content_headers

Additional headers to include (default is None).

TYPE: Union[Mapping[str, str], Dict[str, str], None] DEFAULT: None

Source code in lilya/responses.py 
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def make_headers(
    self, content_headers: Mapping[str, str] | dict[str, str] | None = None
) -> None:
    """
    Initializes the headers based on RFC specifications by setting appropriate conditions and restrictions.

    Args:
        content_headers (Union[Mapping[str, str], Dict[str, str], None], optional): Additional headers to include (default is None).
    """
    headers: dict[str, str] = {} if content_headers is None else content_headers  # type: ignore

    if HeaderHelper.has_entity_header_status(self.status_code):
        headers = HeaderHelper.remove_entity_headers(headers)
    if HeaderHelper.has_body_message(self.status_code):
        content_type = HeaderHelper.get_content_type(
            charset=self.charset, media_type=self.media_type
        )
        if hasattr(self, "body") and self.body is not None:
            headers.setdefault("content-length", str(len(self.body)))

        # Populates the content type if exists
        if content_type is not None:
            headers.setdefault("content-type", content_type)

    raw_headers = [
        (name.encode("utf-8"), f"{value}".encode(errors="surrogateescape"))
        for name, value in headers.items()
    ]
    self.raw_headers = raw_headers

set_cookie(key, value='', *, path='/', domain=None, secure=False, max_age=None, expires=None, httponly=False, samesite='lax')

Sets a cookie in the response headers.

PARAMETER DESCRIPTION
key

TYPE: str

value

TYPE: str DEFAULT: ''

path

TYPE: str DEFAULT: '/'

domain

TYPE: str | None DEFAULT: None

secure

TYPE: bool DEFAULT: False

max_age

TYPE: int | None DEFAULT: None

expires

TYPE: datetime | str | int | None DEFAULT: None

httponly

TYPE: bool DEFAULT: False

samesite

TYPE: Literal['lax', 'strict', 'none'] DEFAULT: 'lax'

PARAMETER DESCRIPTION
key

The name of the cookie.

TYPE: str

value

The value of the cookie.

TYPE: str DEFAULT: ''

path

The path for which the cookie is valid (default is '/').

TYPE: str DEFAULT: '/'

domain

The domain to which the cookie belongs.

TYPE: Union[str, None] DEFAULT: None

secure

If True, the cookie should only be sent over HTTPS.

TYPE: bool DEFAULT: False

max_age

The maximum age of the cookie in seconds.

TYPE: Union[int, None] DEFAULT: None

expires

The expiration date of the cookie.

TYPE: Union[Union[datetime, str, int], None] DEFAULT: None

httponly

If True, the cookie should only be accessible through HTTP.

TYPE: bool DEFAULT: False

samesite

SameSite attribute of the cookie.

TYPE: Literal['lax', 'strict', 'none'] DEFAULT: 'lax'

RAISES DESCRIPTION
AssertionError

If samesite is not one of 'strict', 'lax', or 'none'.
Source code in lilya/responses.py 
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def set_cookie(
    self,
    key: str,
    value: str = "",
    *,
    path: str = "/",
    domain: str | None = None,
    secure: bool = False,
    max_age: int | None = None,
    expires: datetime | str | int | None = None,
    httponly: bool = False,
    samesite: Literal["lax", "strict", "none"] = "lax",
) -> None:
    """
    Sets a cookie in the response headers.

    Args:
        key (str): The name of the cookie.
        value (str, optional): The value of the cookie.
        path (str, optional): The path for which the cookie is valid (default is '/').
        domain (Union[str, None], optional): The domain to which the cookie belongs.
        secure (bool, optional): If True, the cookie should only be sent over HTTPS.
        max_age (Union[int, None], optional): The maximum age of the cookie in seconds.
        expires (Union[Union[datetime, str, int], None], optional): The expiration date of the cookie.
        httponly (bool, optional): If True, the cookie should only be accessible through HTTP.
        samesite (Literal["lax", "strict", "none"], optional): SameSite attribute of the cookie.

    Raises:
        AssertionError: If samesite is not one of 'strict', 'lax', or 'none'.
    """
    cookie: http.cookies.BaseCookie[str] = http.cookies.SimpleCookie()
    cookie[key] = value
    if max_age is not None:
        cookie[key]["max-age"] = max_age
    if expires is not None:
        if isinstance(expires, datetime):
            cookie[key]["expires"] = format_datetime(expires, usegmt=True)
        else:
            cookie[key]["expires"] = expires
    if path is not None:
        cookie[key]["path"] = path
    if domain is not None:
        cookie[key]["domain"] = domain
    if secure:
        cookie[key]["secure"] = True
    if httponly:
        cookie[key]["httponly"] = True
    if samesite is not None:
        assert samesite.lower() in [
            "strict",
            "lax",
            "none",
        ], "samesite must be either 'strict', 'lax' or 'none'"
        cookie[key]["samesite"] = samesite
    cookie_val = cookie.output(header="").strip()
    self.headers.add("set-cookie", cookie_val.encode("utf-8"))

delete_cookie(key, path='/', domain=None, secure=False, httponly=False, samesite='lax')

Deletes a cookie in the response headers by setting its max age and expiration to 0.

PARAMETER DESCRIPTION
key

TYPE: str

path

TYPE: str DEFAULT: '/'

domain

TYPE: str | None DEFAULT: None

secure

TYPE: bool DEFAULT: False

httponly

TYPE: bool DEFAULT: False

samesite

TYPE: Literal['lax', 'strict', 'none'] DEFAULT: 'lax'

PARAMETER DESCRIPTION
key

The name of the cookie to delete.

TYPE: str

path

The path for which the cookie is valid (default is '/').

TYPE: str DEFAULT: '/'

domain

The domain to which the cookie belongs.

TYPE: Union[str, None] DEFAULT: None

secure

If True, the cookie should only be sent over HTTPS.

TYPE: bool DEFAULT: False

httponly

If True, the cookie should only be accessible through HTTP.

TYPE: bool DEFAULT: False

samesite

SameSite attribute of the cookie.

TYPE: Literal['lax', 'strict', 'none'] DEFAULT: 'lax'

Source code in lilya/responses.py 
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def delete_cookie(
    self,
    key: str,
    path: str = "/",
    domain: str | None = None,
    secure: bool = False,
    httponly: bool = False,
    samesite: Literal["lax", "strict", "none"] = "lax",
) -> None:
    """
    Deletes a cookie in the response headers by setting its max age and expiration to 0.

    Args:
        key (str): The name of the cookie to delete.
        path (str, optional): The path for which the cookie is valid (default is '/').
        domain (Union[str, None], optional): The domain to which the cookie belongs.
        secure (bool, optional): If True, the cookie should only be sent over HTTPS.
        httponly (bool, optional): If True, the cookie should only be accessible through HTTP.
        samesite (Literal["lax", "strict", "none"], optional): SameSite attribute of the cookie.
    """
    self.set_cookie(
        key,
        max_age=0,
        expires=0,
        path=path,
        domain=domain,
        secure=secure,
        httponly=httponly,
        samesite=samesite,
    )

message 

message(prefix)
PARAMETER DESCRIPTION
prefix

TYPE: str

Source code in lilya/responses.py 
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def message(self, prefix: str) -> dict[str, Any]:
    return {
        "type": prefix + "http.response.start",
        "status": self.status_code,
        "headers": self.encoded_headers,
    }

transform staticmethod 

transform(value)

The transformation of the data being returned.

Supports all the default encoders from Lilya and custom from Esmerald.

PARAMETER DESCRIPTION
value

TYPE: Any

Source code in esmerald/responses/base.py 
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@staticmethod
def transform(value: Any) -> Dict[str, Any]:
    """
    The transformation of the data being returned.

    Supports all the default encoders from Lilya and custom from Esmerald.
    """
    return cast(Dict[str, Any], json_encoder(value))

make_response 

make_response(content)
PARAMETER DESCRIPTION
content

TYPE: Any

Source code in esmerald/responses/base.py 
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def make_response(self, content: Any) -> Union[bytes, str]:
    try:
        if (
            content is None
            or content is NoReturn
            and (
                self.status_code < 100
                or self.status_code
                in {status.HTTP_204_NO_CONTENT, status.HTTP_304_NOT_MODIFIED}
            )
        ):
            return b""
        if self.media_type == MediaType.JSON:
            return dumps(
                content,
                default=self.transform,
                option=OPT_SERIALIZE_NUMPY | OPT_OMIT_MICROSECONDS,
            )
        return super().make_response(content)
    except (AttributeError, ValueError, TypeError) as e:  # pragma: no cover
        raise ImproperlyConfigured("Unable to serialize response content") from e