client.py 文件源码

def _handle_redirects(self, response, **extra):
        "Follows any redirects by requesting responses from the server using GET."

        response.redirect_chain = []
        while response.status_code in (301, 302, 303, 307):
            response_url = response.url
            redirect_chain = response.redirect_chain
            redirect_chain.append((response_url, response.status_code))

            url = urlsplit(response_url)
            if url.scheme:
                extra['wsgi.url_scheme'] = url.scheme
            if url.hostname:
                extra['SERVER_NAME'] = url.hostname
            if url.port:
                extra['SERVER_PORT'] = str(url.port)

            # Prepend the request path to handle relative path redirects
            path = url.path
            if not path.startswith('/'):
                path = urljoin(response.request['PATH_INFO'], path)

            response = self.get(path, QueryDict(url.query), follow=False, **extra)
            response.redirect_chain = redirect_chain

            if redirect_chain[-1] in redirect_chain[:-1]:
                # Check that we're not redirecting to somewhere we've already
                # been to, to prevent loops.
                raise RedirectCycleError("Redirect loop detected.", last_response=response)
            if len(redirect_chain) > 20:
                # Such a lengthy chain likely also means a loop, but one with
                # a growing path, changing view, or changing query argument;
                # 20 is the value of "network.http.redirection-limit" from Firefox.
                raise RedirectCycleError("Too many redirects.", last_response=response)

        return response