New submission from Matt Martz <m...@sivel.net>:
HTTPError may not be fully initialized in some scenarios leading to an inconsistent interface. This is documented in code at: https://github.com/python/cpython/blob/55fe1ae9708d81b902b6fe8f6590e2a24b1bd4b0/Lib/urllib/error.py#L45-L50 Unfortunately the way this is implemented creates an inconsistent interface, and opaque code, without a number of inline comments explaining the behavior of HTTPError. Additionally, the way that it currently works, will cause a KeyError to be raised from tempfile, which is rather confusing. Instead of "partially initializing" the HTTPError object, I'd propose that when fp is None, that we provide it with something like io.BytesIO to fulfill the interface. There may be other recommended solutions, I've not thought through this extensively yet. I think I just prefer always calling self.__super_init but passing in something like io.BytesIO if fp is None I'm willing to create the PR once I know which direction seems to make the most sense. >>> from urllib.error import HTTPError >>> from urllib.request import HTTPDigestAuthHandler, >>> HTTPPasswordMgrWithDefaultRealm, build_opener >>> passman = HTTPPasswordMgrWithDefaultRealm() >>> passman.add_password(None, 'httpbin.org', 'user', 'wrong') >>> opener = build_opener(HTTPDigestAuthHandler(passman)) >>> try: ... opener.open('https://httpbin.org/digest-auth/auth/user/passwd') ... except HTTPError as e: ... e.read() ... Traceback (most recent call last): File "<stdin>", line 2, in <module> File ".../3.10.0/lib/python3.10/urllib/request.py", line 525, in open response = meth(req, response) File ".../3.10.0/lib/python3.10/urllib/request.py", line 634, in http_response response = self.parent.error( File ".../3.10.0/lib/python3.10/urllib/request.py", line 557, in error result = self._call_chain(*args) File ".../3.10.0/lib/python3.10/urllib/request.py", line 496, in _call_chain result = func(*args) File ".../3.10.0/lib/python3.10/urllib/request.py", line 1238, in http_error_401 retry = self.http_error_auth_reqed('www-authenticate', File ".../3.10.0/lib/python3.10/urllib/request.py", line 1111, in http_error_auth_reqed raise HTTPError(req.full_url, 401, "digest auth failed", During handling of the above exception, another exception occurred: Traceback (most recent call last): File "<stdin>", line 4, in <module> File ".../3.10.0/lib/python3.10/tempfile.py", line 473, in __getattr__ file = self.__dict__['file'] KeyError: 'file' ---------- components: Library (Lib) messages: 407482 nosy: sivel priority: normal severity: normal status: open title: Calling read() on HTTPError may cause KeyError in tempfile versions: Python 3.10, Python 3.11, Python 3.6, Python 3.7, Python 3.8, Python 3.9 _______________________________________ Python tracker <rep...@bugs.python.org> <https://bugs.python.org/issue45955> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
