def _ensure_html_response(url: str, session: PipSession) -> None:
"""Send a HEAD request to the URL, and ensure the response contains HTML.
Raises `_NotHTTP` if the URL is not available for a HEAD request, or
`_NotHTML` if the content type is not text/html.
"""
scheme, netloc, path, query, fragment = urllib.parse.urlsplit(url)
if scheme not in {"http", "https"}:
raise _NotHTTP()
resp = session.head(url, allow_redirects=True)
raise_for_status(resp)
_ensure_html_header(resp)
def __init__(
self, url: str, session: PipSession, chunk_size: int = CONTENT_CHUNK_SIZE
) -> None:
head = session.head(url, headers=HEADERS)
raise_for_status(head)
assert head.status_code == 200
self._session, self._url, self._chunk_size = session, url, chunk_size
self._length = int(head.headers["Content-Length"])
self._file = NamedTemporaryFile()
self.truncate(self._length)
self._left: List[int] = []
self._right: List[int] = []
if "bytes" not in head.headers.get("Accept-Ranges", "none"):
raise HTTPRangeRequestUnsupported("range request is not supported")
self._check_zip()
