Source code for scrapy.http.response

"""
This module implements the Response class which is used to represent HTTP
responses in Scrapy.

See documentation in docs/topics/request-response.rst
"""

from __future__ import annotations

from ipaddress import IPv4Address, IPv6Address
from typing import (
    TYPE_CHECKING,
    Any,
    AnyStr,
    Callable,
    Dict,
    Generator,
    Iterable,
    List,
    Mapping,
    Optional,
    Tuple,
    Union,
    cast,
)
from urllib.parse import urljoin

from twisted.internet.ssl import Certificate

from scrapy.exceptions import NotSupported
from scrapy.http.headers import Headers
from scrapy.http.request import Request
from scrapy.link import Link
from scrapy.utils.trackref import object_ref

if TYPE_CHECKING:
    from scrapy.selector import SelectorList


[docs]class Response(object_ref): """An object that represents an HTTP response, which is usually downloaded (by the Downloader) and fed to the Spiders for processing. """ attributes: Tuple[str, ...] = ( "url", "status", "headers", "body", "flags", "request", "certificate", "ip_address", "protocol", ) """A tuple of :class:`str` objects containing the name of all public attributes of the class that are also keyword parameters of the ``__init__`` method. Currently used by :meth:`Response.replace`. """ def __init__( self, url: str, status: int = 200, headers: Union[Mapping[AnyStr, Any], Iterable[Tuple[AnyStr, Any]], None] = None, body: bytes = b"", flags: Optional[List[str]] = None, request: Optional[Request] = None, certificate: Optional[Certificate] = None, ip_address: Union[IPv4Address, IPv6Address, None] = None, protocol: Optional[str] = None, ): self.headers: Headers = Headers(headers or {}) self.status: int = int(status) self._set_body(body) self._set_url(url) self.request: Optional[Request] = request self.flags: List[str] = [] if flags is None else list(flags) self.certificate: Optional[Certificate] = certificate self.ip_address: Union[IPv4Address, IPv6Address, None] = ip_address self.protocol: Optional[str] = protocol @property def cb_kwargs(self) -> Dict[str, Any]: try: return self.request.cb_kwargs # type: ignore[union-attr] except AttributeError: raise AttributeError( "Response.cb_kwargs not available, this response " "is not tied to any request" ) @property def meta(self) -> Dict[str, Any]: try: return self.request.meta # type: ignore[union-attr] except AttributeError: raise AttributeError( "Response.meta not available, this response " "is not tied to any request" ) @property def url(self) -> str: return self._url def _set_url(self, url: str) -> None: if isinstance(url, str): self._url: str = url else: raise TypeError( f"{type(self).__name__} url must be str, " f"got {type(url).__name__}" ) @property def body(self) -> bytes: return self._body def _set_body(self, body: Optional[bytes]) -> None: if body is None: self._body = b"" elif not isinstance(body, bytes): raise TypeError( "Response body must be bytes. " "If you want to pass unicode body use TextResponse " "or HtmlResponse." ) else: self._body = body def __repr__(self) -> str: return f"<{self.status} {self.url}>"
[docs] def copy(self) -> Response: """Return a copy of this Response""" return self.replace()
[docs] def replace(self, *args: Any, **kwargs: Any) -> Response: """Create a new Response with the same attributes except for those given new values""" for x in self.attributes: kwargs.setdefault(x, getattr(self, x)) cls = kwargs.pop("cls", self.__class__) return cast(Response, cls(*args, **kwargs))
[docs] def urljoin(self, url: str) -> str: """Join this Response's url with a possible relative url to form an absolute interpretation of the latter.""" return urljoin(self.url, url)
@property def text(self) -> str: """For subclasses of TextResponse, this will return the body as str """ raise AttributeError("Response content isn't text") def css(self, *a: Any, **kw: Any) -> SelectorList: """Shortcut method implemented only by responses whose content is text (subclasses of TextResponse). """ raise NotSupported("Response content isn't text") def jmespath(self, *a: Any, **kw: Any) -> SelectorList: """Shortcut method implemented only by responses whose content is text (subclasses of TextResponse). """ raise NotSupported("Response content isn't text") def xpath(self, *a: Any, **kw: Any) -> SelectorList: """Shortcut method implemented only by responses whose content is text (subclasses of TextResponse). """ raise NotSupported("Response content isn't text")
[docs] def follow( self, url: Union[str, Link], callback: Optional[Callable] = None, method: str = "GET", headers: Union[Mapping[AnyStr, Any], Iterable[Tuple[AnyStr, Any]], None] = None, body: Optional[Union[bytes, str]] = None, cookies: Optional[Union[dict, List[dict]]] = None, meta: Optional[Dict[str, Any]] = None, encoding: Optional[str] = "utf-8", priority: int = 0, dont_filter: bool = False, errback: Optional[Callable] = None, cb_kwargs: Optional[Dict[str, Any]] = None, flags: Optional[List[str]] = None, ) -> Request: """ Return a :class:`~.Request` instance to follow a link ``url``. It accepts the same arguments as ``Request.__init__`` method, but ``url`` can be a relative URL or a ``scrapy.link.Link`` object, not only an absolute URL. :class:`~.TextResponse` provides a :meth:`~.TextResponse.follow` method which supports selectors in addition to absolute/relative URLs and Link objects. .. versionadded:: 2.0 The *flags* parameter. """ if encoding is None: raise ValueError("encoding can't be None") if isinstance(url, Link): url = url.url elif url is None: raise ValueError("url can't be None") url = self.urljoin(url) return Request( url=url, callback=callback, method=method, headers=headers, body=body, cookies=cookies, meta=meta, encoding=encoding, priority=priority, dont_filter=dont_filter, errback=errback, cb_kwargs=cb_kwargs, flags=flags, )
[docs] def follow_all( self, urls: Iterable[Union[str, Link]], callback: Optional[Callable] = None, method: str = "GET", headers: Union[Mapping[AnyStr, Any], Iterable[Tuple[AnyStr, Any]], None] = None, body: Optional[Union[bytes, str]] = None, cookies: Optional[Union[dict, List[dict]]] = None, meta: Optional[Dict[str, Any]] = None, encoding: Optional[str] = "utf-8", priority: int = 0, dont_filter: bool = False, errback: Optional[Callable] = None, cb_kwargs: Optional[Dict[str, Any]] = None, flags: Optional[List[str]] = None, ) -> Generator[Request, None, None]: """ .. versionadded:: 2.0 Return an iterable of :class:`~.Request` instances to follow all links in ``urls``. It accepts the same arguments as ``Request.__init__`` method, but elements of ``urls`` can be relative URLs or :class:`~scrapy.link.Link` objects, not only absolute URLs. :class:`~.TextResponse` provides a :meth:`~.TextResponse.follow_all` method which supports selectors in addition to absolute/relative URLs and Link objects. """ if not hasattr(urls, "__iter__"): raise TypeError("'urls' argument must be an iterable") return ( self.follow( url=url, callback=callback, method=method, headers=headers, body=body, cookies=cookies, meta=meta, encoding=encoding, priority=priority, dont_filter=dont_filter, errback=errback, cb_kwargs=cb_kwargs, flags=flags, ) for url in urls )