Coverage for requests/utils.py: 16%

# Coverage for requests/utils.py : 16%

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""" import cgi import codecs import collections import contextlib import io import os import platform import re import socket import struct import warnings from .__version__ import __version__ from . import certs # to_native_string is unused here, but imported here for backwards compatibility from ._internal_utils import to_native_string from .compat import parse_http_list as _parse_list_header from .compat import ( quote, urlparse, bytes, str, OrderedDict, unquote, getproxies, proxy_bypass, urlunparse, basestring, integer_types, is_py3, proxy_bypass_environment, getproxies_environment) from .cookies import cookiejar_from_dict from .structures import CaseInsensitiveDict from .exceptions import ( InvalidURL, InvalidHeader, FileModeWarning, UnrewindableBodyError) NETRC_FILES = ('.netrc', '_netrc') DEFAULT_CA_BUNDLE_PATH = certs.where() if platform.system() == 'Windows': # provide a proxy_bypass version on Windows without DNS lookups def proxy_bypass_registry(host): if is_py3: import winreg else: import _winreg as winreg try: internetSettings = winreg.OpenKey(winreg.HKEY_CURRENT_USER, r'Software\Microsoft\Windows\CurrentVersion\Internet Settings') proxyEnable = winreg.QueryValueEx(internetSettings, 'ProxyEnable')[0] proxyOverride = winreg.QueryValueEx(internetSettings, 'ProxyOverride')[0] except OSError: return False if not proxyEnable or not proxyOverride: return False # make a check value list from the registry entry: replace the # '<local>' string by the localhost entry and the corresponding # canonical entry. proxyOverride = proxyOverride.split(';') # now check if we match one of the registry values. for test in proxyOverride: if test == '<local>': if '.' not in host: return True test = test.replace(".", r"\.") # mask dots test = test.replace("*", r".*") # change glob sequence test = test.replace("?", r".") # change glob char if re.match(test, host, re.I): return True return False def proxy_bypass(host): # noqa """Return True, if the host should be bypassed. Checks proxy settings gathered from the environment, if specified, or the registry. """ if getproxies_environment(): return proxy_bypass_environment(host) else: return proxy_bypass_registry(host) def dict_to_sequence(d): """Returns an internal sequence dictionary update.""" if hasattr(d, 'items'): d = d.items() return d def super_len(o): total_length = None current_position = 0 if hasattr(o, '__len__'): total_length = len(o) elif hasattr(o, 'len'): total_length = o.len elif hasattr(o, 'fileno'): try: fileno = o.fileno() except io.UnsupportedOperation: pass else: total_length = os.fstat(fileno).st_size # Having used fstat to determine the file length, we need to # confirm that this file was opened up in binary mode. if 'b' not in o.mode: warnings.warn(( "Requests has determined the content-length for this " "request using the binary size of the file: however, the " "file has been opened in text mode (i.e. without the 'b' " "flag in the mode). This may lead to an incorrect " "content-length. In Requests 3.0, support will be removed " "for files in text mode."), FileModeWarning ) if hasattr(o, 'tell'): try: current_position = o.tell() except (OSError, IOError): # This can happen in some weird situations, such as when the file # is actually a special file descriptor like stdin. In this # instance, we don't know what the length is, so set it to zero and # let requests chunk it instead. if total_length is not None: current_position = total_length else: if hasattr(o, 'seek') and total_length is None: # StringIO and BytesIO have seek but no useable fileno try: # seek to end of file o.seek(0, 2) total_length = o.tell() # seek back to current position to support # partially read file-like objects o.seek(current_position or 0) except (OSError, IOError): total_length = 0 if total_length is None: total_length = 0 return max(0, total_length - current_position) def get_netrc_auth(url, raise_errors=False): """Returns the Requests tuple auth for a given url from netrc.""" try: from netrc import netrc, NetrcParseError netrc_path = None for f in NETRC_FILES: try: loc = os.path.expanduser('~/{0}'.format(f)) except KeyError: # os.path.expanduser can fail when $HOME is undefined and # getpwuid fails. See http://bugs.python.org/issue20164 & # https://github.com/requests/requests/issues/1846 return if os.path.exists(loc): netrc_path = loc break # Abort early if there isn't one. if netrc_path is None: return ri = urlparse(url) # Strip port numbers from netloc. This weird `if...encode`` dance is # used for Python 3.2, which doesn't support unicode literals. splitstr = b':' if isinstance(url, str): splitstr = splitstr.decode('ascii') host = ri.netloc.split(splitstr)[0] try: _netrc = netrc(netrc_path).authenticators(host) if _netrc: # Return with login / password login_i = (0 if _netrc[0] else 1) return (_netrc[login_i], _netrc[2]) except (NetrcParseError, IOError): # If there was a parsing error or a permissions issue reading the file, # we'll just skip netrc auth unless explicitly asked to raise errors. if raise_errors: raise # AppEngine hackiness. except (ImportError, AttributeError): pass def guess_filename(obj): """Tries to guess the filename of the given object.""" name = getattr(obj, 'name', None) if (name and isinstance(name, basestring) and name[0] != '<' and name[-1] != '>'): return os.path.basename(name) def from_key_val_list(value): """Take an object and test to see if it can be represented as a dictionary. Unless it can not be represented as such, return an OrderedDict, e.g., :: >>> from_key_val_list([('key', 'val')]) OrderedDict([('key', 'val')]) >>> from_key_val_list('string') ValueError: need more than 1 value to unpack >>> from_key_val_list({'key': 'val'}) OrderedDict([('key', 'val')]) :rtype: OrderedDict """ if value is None: return None if isinstance(value, (str, bytes, bool, int)): raise ValueError('cannot encode objects that are not 2-tuples') return OrderedDict(value) def to_key_val_list(value): """Take an object and test to see if it can be represented as a dictionary. If it can be, return a list of tuples, e.g., :: >>> to_key_val_list([('key', 'val')]) [('key', 'val')] >>> to_key_val_list({'key': 'val'}) [('key', 'val')] >>> to_key_val_list('string') ValueError: cannot encode objects that are not 2-tuples. :rtype: list """ if value is None: return None if isinstance(value, (str, bytes, bool, int)): raise ValueError('cannot encode objects that are not 2-tuples') if isinstance(value, collections.Mapping): value = value.items() return list(value) # From mitsuhiko/werkzeug (used with permission). def parse_list_header(value): """Parse lists as described by RFC 2068 Section 2. In particular, parse comma-separated lists where the elements of the list may include quoted-strings. A quoted-string could contain a comma. A non-quoted string could have quotes in the middle. Quotes are removed automatically after parsing. It basically works like :func:`parse_set_header` just that items may appear multiple times and case sensitivity is preserved. The return value is a standard :class:`list`: >>> parse_list_header('token, "quoted value"') ['token', 'quoted value'] To create a header from the :class:`list` again, use the :func:`dump_header` function. :param value: a string with a list header. :return: :class:`list` :rtype: list """ result = [] for item in _parse_list_header(value): if item[:1] == item[-1:] == '"': item = unquote_header_value(item[1:-1]) result.append(item) return result # From mitsuhiko/werkzeug (used with permission). def parse_dict_header(value): """Parse lists of key, value pairs as described by RFC 2068 Section 2 and convert them into a python dict: >>> d = parse_dict_header('foo="is a fish", bar="as well"') >>> type(d) is dict True >>> sorted(d.items()) [('bar', 'as well'), ('foo', 'is a fish')] If there is no value for a key it will be `None`: >>> parse_dict_header('key_without_value') {'key_without_value': None} To create a header from the :class:`dict` again, use the :func:`dump_header` function. :param value: a string with a dict header. :return: :class:`dict` :rtype: dict """ result = {} for item in _parse_list_header(value): if '=' not in item: result[item] = None continue name, value = item.split('=', 1) if value[:1] == value[-1:] == '"': value = unquote_header_value(value[1:-1]) result[name] = value return result # From mitsuhiko/werkzeug (used with permission). def unquote_header_value(value, is_filename=False): r"""Unquotes a header value. (Reversal of :func:`quote_header_value`). This does not use the real unquoting but what browsers are actually using for quoting. :param value: the header value to unquote. :rtype: str """ if value and value[0] == value[-1] == '"': # this is not the real unquoting, but fixing this so that the # RFC is met will result in bugs with internet explorer and # probably some other browsers as well. IE for example is # uploading files with "C:\foo\bar.txt" as filename value = value[1:-1] # if this is a filename and the starting characters look like # a UNC path, then just return the value without quotes. Using the # replace sequence below on a UNC path has the effect of turning # the leading double slash into a single slash and then # _fix_ie_filename() doesn't work correctly. See #458. if not is_filename or value[:2] != '\\\\': return value.replace('\\\\', '\\').replace('\\"', '"') return value def dict_from_cookiejar(cj): """Returns a key/value dictionary from a CookieJar. :param cj: CookieJar object to extract cookies from. :rtype: dict """ cookie_dict = {} for cookie in cj: cookie_dict[cookie.name] = cookie.value return cookie_dict def add_dict_to_cookiejar(cj, cookie_dict): """Returns a CookieJar from a key/value dictionary. :param cj: CookieJar to insert cookies into. :param cookie_dict: Dict of key/values to insert into CookieJar. :rtype: CookieJar """ return cookiejar_from_dict(cookie_dict, cj) def get_encodings_from_content(content): """Returns encodings from given content string. :param content: bytestring to extract encodings from. """ warnings.warn(( 'In requests 3.0, get_encodings_from_content will be removed. For ' 'more information, please see the discussion on issue #2266. (This' ' warning should only appear once.)'), DeprecationWarning) charset_re = re.compile(r'<meta.*?charset=["\']*(.+?)["\'>]', flags=re.I) pragma_re = re.compile(r'<meta.*?content=["\']*;?charset=(.+?)["\'>]', flags=re.I) xml_re = re.compile(r'^<\?xml.*?encoding=["\']*(.+?)["\'>]') return (charset_re.findall(content) + pragma_re.findall(content) + xml_re.findall(content)) def get_encoding_from_headers(headers): """Returns encodings from given HTTP Header Dict. :param headers: dictionary to extract encoding from. :rtype: str """ content_type = headers.get('content-type') if not content_type: return None content_type, params = cgi.parse_header(content_type) if 'charset' in params: return params['charset'].strip("'\"") if 'text' in content_type: return 'ISO-8859-1' def stream_decode_response_unicode(iterator, r): """Stream decodes a iterator.""" if r.encoding is None: for item in iterator: yield item return decoder = codecs.getincrementaldecoder(r.encoding)(errors='replace') for chunk in iterator: rv = decoder.decode(chunk) if rv: yield rv rv = decoder.decode(b'', final=True) if rv: yield rv def iter_slices(string, slice_length): """Iterate over slices of a string.""" pos = 0 if slice_length is None or slice_length <= 0: slice_length = len(string) while pos < len(string): yield string[pos: pos + slice_length] pos += slice_length def get_unicode_from_response(r): """Returns the requested content back in unicode. :param r: Response object to get unicode content from. Tried: 1. charset from content-type 2. fall back and replace all unicode characters :rtype: str """ warnings.warn(( 'In requests 3.0, get_unicode_from_response will be removed. For ' 'more information, please see the discussion on issue #2266. (This' ' warning should only appear once.)'), DeprecationWarning) tried_encodings = [] # Try charset from content-type encoding = get_encoding_from_headers(r.headers) if encoding: try: return str(r.content, encoding) except UnicodeError: tried_encodings.append(encoding) # Fall back: try: return str(r.content, encoding, errors='replace') except TypeError: return r.content # The unreserved URI characters (RFC 3986) UNRESERVED_SET = frozenset( "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz" + "0123456789-._~") def unquote_unreserved(uri): """Un-escape any percent-escape sequences in a URI that are unreserved characters. This leaves all reserved, illegal and non-ASCII bytes encoded. :rtype: str """ parts = uri.split('%') for i in range(1, len(parts)): h = parts[i][0:2] if len(h) == 2 and h.isalnum(): try: c = chr(int(h, 16)) except ValueError: raise InvalidURL("Invalid percent-escape sequence: '%s'" % h) if c in UNRESERVED_SET: parts[i] = c + parts[i][2:] else: parts[i] = '%' + parts[i] else: parts[i] = '%' + parts[i] return ''.join(parts) def requote_uri(uri): """Re-quote the given URI. This function passes the given URI through an unquote/quote cycle to ensure that it is fully and consistently quoted. :rtype: str """ safe_with_percent = "!#$%&'()*+,/:;=?@[]~" safe_without_percent = "!#$&'()*+,/:;=?@[]~" try: # Unquote only the unreserved characters # Then quote only illegal characters (do not quote reserved, # unreserved, or '%') return quote(unquote_unreserved(uri), safe=safe_with_percent) except InvalidURL: # We couldn't unquote the given URI, so let's try quoting it, but # there may be unquoted '%'s in the URI. We need to make sure they're # properly quoted so they do not cause issues elsewhere. return quote(uri, safe=safe_without_percent) def address_in_network(ip, net): """This function allows you to check if an IP belongs to a network subnet Example: returns True if ip = 192.168.1.1 and net = 192.168.1.0/24 returns False if ip = 192.168.1.1 and net = 192.168.100.0/24 :rtype: bool """ ipaddr = struct.unpack('=L', socket.inet_aton(ip))[0] netaddr, bits = net.split('/') netmask = struct.unpack('=L', socket.inet_aton(dotted_netmask(int(bits))))[0] network = struct.unpack('=L', socket.inet_aton(netaddr))[0] & netmask return (ipaddr & netmask) == (network & netmask) def dotted_netmask(mask): """Converts mask from /xx format to xxx.xxx.xxx.xxx Example: if mask is 24 function returns 255.255.255.0 :rtype: str """ bits = 0xffffffff ^ (1 << 32 - mask) - 1 return socket.inet_ntoa(struct.pack('>I', bits)) def is_ipv4_address(string_ip): """ :rtype: bool """ try: socket.inet_aton(string_ip) except socket.error: return False return True def is_valid_cidr(string_network): """ Very simple check of the cidr format in no_proxy variable. :rtype: bool """ if string_network.count('/') == 1: try: mask = int(string_network.split('/')[1]) except ValueError: return False if mask < 1 or mask > 32: return False try: socket.inet_aton(string_network.split('/')[0]) except socket.error: return False else: return False return True @contextlib.contextmanager def set_environ(env_name, value): """Set the environment variable 'env_name' to 'value' Save previous value, yield, and then restore the previous value stored in the environment variable 'env_name'. If 'value' is None, do nothing""" value_changed = value is not None if value_changed: old_value = os.environ.get(env_name) os.environ[env_name] = value try: yield finally: if value_changed: if old_value is None: del os.environ[env_name] else: os.environ[env_name] = old_value def should_bypass_proxies(url, no_proxy): """ Returns whether we should bypass proxies or not. :rtype: bool """ get_proxy = lambda k: os.environ.get(k) or os.environ.get(k.upper()) # First check whether no_proxy is defined. If it is, check that the URL # we're getting isn't in the no_proxy list. no_proxy_arg = no_proxy if no_proxy is None: no_proxy = get_proxy('no_proxy') netloc = urlparse(url).netloc if no_proxy: # We need to check whether we match here. We need to see if we match # the end of the netloc, both with and without the port. no_proxy = ( host for host in no_proxy.replace(' ', '').split(',') if host ) ip = netloc.split(':')[0] if is_ipv4_address(ip): for proxy_ip in no_proxy: if is_valid_cidr(proxy_ip): if address_in_network(ip, proxy_ip): return True elif ip == proxy_ip: # If no_proxy ip was defined in plain IP notation instead of cidr notation & # matches the IP of the index return True else: for host in no_proxy: if netloc.endswith(host) or netloc.split(':')[0].endswith(host): # The URL does match something in no_proxy, so we don't want # to apply the proxies on this URL. return True # If the system proxy settings indicate that this URL should be bypassed, # don't proxy. # The proxy_bypass function is incredibly buggy on OS X in early versions # of Python 2.6, so allow this call to fail. Only catch the specific # exceptions we've seen, though: this call failing in other ways can reveal # legitimate problems. with set_environ('no_proxy', no_proxy_arg): try: bypass = proxy_bypass(netloc) except (TypeError, socket.gaierror): bypass = False if bypass: return True return False def get_environ_proxies(url, no_proxy=None): """ Return a dict of environment proxies. :rtype: dict """ if should_bypass_proxies(url, no_proxy=no_proxy): return {} else: return getproxies() def select_proxy(url, proxies): """Select a proxy for the url, if applicable. :param url: The url being for the request :param proxies: A dictionary of schemes or schemes and hosts to proxy URLs """ proxies = proxies or {} urlparts = urlparse(url) if urlparts.hostname is None: return proxies.get(urlparts.scheme, proxies.get('all')) proxy_keys = [ urlparts.scheme + '://' + urlparts.hostname, urlparts.scheme, 'all://' + urlparts.hostname, 'all', ] proxy = None for proxy_key in proxy_keys: if proxy_key in proxies: proxy = proxies[proxy_key] break return proxy def default_user_agent(name="python-requests"): """ Return a string representing the default user agent. :rtype: str """ return '%s/%s' % (name, __version__) def default_headers(): """ :rtype: requests.structures.CaseInsensitiveDict """ return CaseInsensitiveDict({ 'User-Agent': default_user_agent(), 'Accept-Encoding': ', '.join(('gzip', 'deflate')), 'Accept': '*/*', 'Connection': 'keep-alive', }) def parse_header_links(value): """Return a dict of parsed link headers proxies. i.e. Link: <http:/.../front.jpeg>; rel=front; type="image/jpeg",<http://.../back.jpeg>; rel=back;type="image/jpeg" :rtype: list """ links = [] replace_chars = ' \'"' for val in re.split(', *<', value): try: url, params = val.split(';', 1) except ValueError: url, params = val, '' link = {'url': url.strip('<> \'"')} for param in params.split(';'): try: key, value = param.split('=') except ValueError: break link[key.strip(replace_chars)] = value.strip(replace_chars) links.append(link) return links # Null bytes; no need to recreate these on each call to guess_json_utf _null = '\x00'.encode('ascii') # encoding to ASCII for Python 3 _null2 = _null * 2 _null3 = _null * 3 def guess_json_utf(data): """ :rtype: str """ # JSON always starts with two ASCII characters, so detection is as # easy as counting the nulls and from their location and count # determine the encoding. Also detect a BOM, if present. sample = data[:4] if sample in (codecs.BOM_UTF32_LE, codecs.BOM_UTF32_BE): return 'utf-32' # BOM included if sample[:3] == codecs.BOM_UTF8: return 'utf-8-sig' # BOM included, MS style (discouraged) if sample[:2] in (codecs.BOM_UTF16_LE, codecs.BOM_UTF16_BE): return 'utf-16' # BOM included nullcount = sample.count(_null) if nullcount == 0: return 'utf-8' if nullcount == 2: if sample[::2] == _null2: # 1st and 3rd are null return 'utf-16-be' if sample[1::2] == _null2: # 2nd and 4th are null return 'utf-16-le' # Did not detect 2 valid UTF-16 ascii-range characters if nullcount == 3: if sample[:3] == _null3: return 'utf-32-be' if sample[1:] == _null3: return 'utf-32-le' # Did not detect a valid UTF-32 ascii-range character return None def prepend_scheme_if_needed(url, new_scheme): """Given a URL that may or may not have a scheme, prepend the given scheme. Does not replace a present scheme with the one provided as an argument. :rtype: str """ scheme, netloc, path, params, query, fragment = urlparse(url, new_scheme) # urlparse is a finicky beast, and sometimes decides that there isn't a # netloc present. Assume that it's being over-cautious, and switch netloc # and path if urlparse decided there was no netloc. if not netloc: netloc, path = path, netloc return urlunparse((scheme, netloc, path, params, query, fragment)) def get_auth_from_url(url): """Given a url with authentication components, extract them into a tuple of username,password. :rtype: (str,str) """ parsed = urlparse(url) try: auth = (unquote(parsed.username), unquote(parsed.password)) except (AttributeError, TypeError): auth = ('', '') return auth # Moved outside of function to avoid recompile every call _CLEAN_HEADER_REGEX_BYTE = re.compile(b'^\\S[^\\r\\n]*$|^$') _CLEAN_HEADER_REGEX_STR = re.compile(r'^\S[^\r\n]*$|^$') def check_header_validity(header): """Verifies that header value is a string which doesn't contain leading whitespace or return characters. This prevents unintended header injection. :param header: tuple, in the format (name, value). """ name, value = header if isinstance(value, bytes): pat = _CLEAN_HEADER_REGEX_BYTE else: pat = _CLEAN_HEADER_REGEX_STR try: if not pat.match(value): raise InvalidHeader("Invalid return character or leading space in header: %s" % name) except TypeError: raise InvalidHeader("Value for header {%s: %s} must be of type str or " "bytes, not %s" % (name, value, type(value))) def urldefragauth(url): """ Given a url remove the fragment and the authentication part. :rtype: str """ scheme, netloc, path, params, query, fragment = urlparse(url) # see func:`prepend_scheme_if_needed` if not netloc: netloc, path = path, netloc netloc = netloc.rsplit('@', 1)[-1] return urlunparse((scheme, netloc, path, params, query, '')) def rewind_body(prepared_request): """Move file pointer back to its recorded starting position so it can be read again on redirect. """ body_seek = getattr(prepared_request.body, 'seek', None) if body_seek is not None and isinstance(prepared_request._body_position, integer_types): try: body_seek(prepared_request._body_position) except (IOError, OSError): raise UnrewindableBodyError("An error occurred when rewinding request " "body for redirect.") else: raise UnrewindableBodyError("Unable to rewind request body for redirect.")