Edit File: httplib.py
r"""HTTP/1.1 client library <intro stuff goes here> <other stuff, too> HTTPConnection goes through a number of "states", which define when a client may legally make another request or fetch the response for a particular request. This diagram details these state transitions: (null) | | HTTPConnection() v Idle | | putrequest() v Request-started | | ( putheader() )* endheaders() v Request-sent | | response = getresponse() v Unread-response [Response-headers-read] |\____________________ | | | response.read() | putrequest() v v Idle Req-started-unread-response ______/| / | response.read() | | ( putheader() )* endheaders() v v Request-started Req-sent-unread-response | | response.read() v Request-sent This diagram presents the following rules: -- a second request may not be started until {response-headers-read} -- a response [object] cannot be retrieved until {request-sent} -- there is no differentiation between an unread response body and a partially read response body Note: this enforcement is applied by the HTTPConnection class. The HTTPResponse class does not enforce this state machine, which implies sophisticated clients may accelerate the request/response pipeline. Caution should be taken, though: accelerating the states beyond the above pattern may imply knowledge of the server's connection-close behavior for certain requests. For example, it is impossible to tell whether the server will close the connection UNTIL the response headers have been read; this means that further requests cannot be placed into the pipeline until it is known that the server will NOT be closing the connection. Logical State __state __response ------------- ------- ---------- Idle _CS_IDLE None Request-started _CS_REQ_STARTED None Request-sent _CS_REQ_SENT None Unread-response _CS_IDLE <response_class> Req-started-unread-response _CS_REQ_STARTED <response_class> Req-sent-unread-response _CS_REQ_SENT <response_class> """ from array import array import os import re import socket from sys import py3kwarning from urlparse import urlsplit import warnings with warnings.catch_warnings(): if py3kwarning: warnings.filterwarnings("ignore", ".*mimetools has been removed", DeprecationWarning) import mimetools try: from cStringIO import StringIO except ImportError: from StringIO import StringIO __all__ = ["HTTP", "HTTPResponse", "HTTPConnection", "HTTPException", "NotConnected", "UnknownProtocol", "UnknownTransferEncoding", "UnimplementedFileMode", "IncompleteRead", "InvalidURL", "ImproperConnectionState", "CannotSendRequest", "CannotSendHeader", "ResponseNotReady", "BadStatusLine", "error", "responses"] HTTP_PORT = 80 HTTPS_PORT = 443 _UNKNOWN = 'UNKNOWN' # connection states _CS_IDLE = 'Idle' _CS_REQ_STARTED = 'Request-started' _CS_REQ_SENT = 'Request-sent' # status codes # informational CONTINUE = 100 SWITCHING_PROTOCOLS = 101 PROCESSING = 102 # successful OK = 200 CREATED = 201 ACCEPTED = 202 NON_AUTHORITATIVE_INFORMATION = 203 NO_CONTENT = 204 RESET_CONTENT = 205 PARTIAL_CONTENT = 206 MULTI_STATUS = 207 IM_USED = 226 # redirection MULTIPLE_CHOICES = 300 MOVED_PERMANENTLY = 301 FOUND = 302 SEE_OTHER = 303 NOT_MODIFIED = 304 USE_PROXY = 305 TEMPORARY_REDIRECT = 307 # client error BAD_REQUEST = 400 UNAUTHORIZED = 401 PAYMENT_REQUIRED = 402 FORBIDDEN = 403 NOT_FOUND = 404 METHOD_NOT_ALLOWED = 405 NOT_ACCEPTABLE = 406 PROXY_AUTHENTICATION_REQUIRED = 407 REQUEST_TIMEOUT = 408 CONFLICT = 409 GONE = 410 LENGTH_REQUIRED = 411 PRECONDITION_FAILED = 412 REQUEST_ENTITY_TOO_LARGE = 413 REQUEST_URI_TOO_LONG = 414 UNSUPPORTED_MEDIA_TYPE = 415 REQUESTED_RANGE_NOT_SATISFIABLE = 416 EXPECTATION_FAILED = 417 UNPROCESSABLE_ENTITY = 422 LOCKED = 423 FAILED_DEPENDENCY = 424 UPGRADE_REQUIRED = 426 # server error INTERNAL_SERVER_ERROR = 500 NOT_IMPLEMENTED = 501 BAD_GATEWAY = 502 SERVICE_UNAVAILABLE = 503 GATEWAY_TIMEOUT = 504 HTTP_VERSION_NOT_SUPPORTED = 505 INSUFFICIENT_STORAGE = 507 NOT_EXTENDED = 510 # Mapping status codes to official W3C names responses = { 100: 'Continue', 101: 'Switching Protocols', 200: 'OK', 201: 'Created', 202: 'Accepted', 203: 'Non-Authoritative Information', 204: 'No Content', 205: 'Reset Content', 206: 'Partial Content', 300: 'Multiple Choices', 301: 'Moved Permanently', 302: 'Found', 303: 'See Other', 304: 'Not Modified', 305: 'Use Proxy', 306: '(Unused)', 307: 'Temporary Redirect', 400: 'Bad Request', 401: 'Unauthorized', 402: 'Payment Required', 403: 'Forbidden', 404: 'Not Found', 405: 'Method Not Allowed', 406: 'Not Acceptable', 407: 'Proxy Authentication Required', 408: 'Request Timeout', 409: 'Conflict', 410: 'Gone', 411: 'Length Required', 412: 'Precondition Failed', 413: 'Request Entity Too Large', 414: 'Request-URI Too Long', 415: 'Unsupported Media Type', 416: 'Requested Range Not Satisfiable', 417: 'Expectation Failed', 500: 'Internal Server Error', 501: 'Not Implemented', 502: 'Bad Gateway', 503: 'Service Unavailable', 504: 'Gateway Timeout', 505: 'HTTP Version Not Supported', } # maximal amount of data to read at one time in _safe_read MAXAMOUNT = 1048576 # maximal line length when calling readline(). _MAXLINE = 65536 # maximum amount of headers accepted _MAXHEADERS = 100 # Header name/value ABNF (http://tools.ietf.org/html/rfc7230#section-3.2) # # VCHAR = %x21-7E # obs-text = %x80-FF # header-field = field-name ":" OWS field-value OWS # field-name = token # field-value = *( field-content / obs-fold ) # field-content = field-vchar [ 1*( SP / HTAB ) field-vchar ] # field-vchar = VCHAR / obs-text # # obs-fold = CRLF 1*( SP / HTAB ) # ; obsolete line folding # ; see Section 3.2.4 # token = 1*tchar # # tchar = "!" / "#" / "$" / "%" / "&" / "'" / "*" # / "+" / "-" / "." / "^" / "_" / "`" / "|" / "~" # / DIGIT / ALPHA # ; any VCHAR, except delimiters # # VCHAR defined in http://tools.ietf.org/html/rfc5234#appendix-B.1 # the patterns for both name and value are more lenient than RFC # definitions to allow for backwards compatibility _is_legal_header_name = re.compile(r'\A[^:\s][^:\r\n]*\Z').match _is_illegal_header_value = re.compile(r'\n(?![ \t])|\r(?![ \t\n])').search # These characters are not allowed within HTTP URL paths. # See https://tools.ietf.org/html/rfc3986#section-3.3 and the # https://tools.ietf.org/html/rfc3986#appendix-A pchar definition. # Prevents CVE-2019-9740. Includes control characters such as \r\n. # Restrict non-ASCII characters above \x7f (0x80-0xff). _contains_disallowed_url_pchar_re = re.compile('[\x00-\x20\x7f-\xff]') # Arguably only these _should_ allowed: # _is_allowed_url_pchars_re = re.compile(r"^[/!$&'()*+,;=:@%a-zA-Z0-9._~-]+$") # We are more lenient for assumed real world compatibility purposes. # These characters are not allowed within HTTP method names # to prevent http header injection. _contains_disallowed_method_pchar_re = re.compile('[\x00-\x1f]') # We always set the Content-Length header for these methods because some # servers will otherwise respond with a 411 _METHODS_EXPECTING_BODY = {'PATCH', 'POST', 'PUT'} class HTTPMessage(mimetools.Message): def addheader(self, key, value): """Add header for field key handling repeats.""" prev = self.dict.get(key) if prev is None: self.dict[key] = value else: combined = ", ".join((prev, value)) self.dict[key] = combined def addcontinue(self, key, more): """Add more field data from a continuation line.""" prev = self.dict[key] self.dict[key] = prev + "\n " + more def readheaders(self): """Read header lines. Read header lines up to the entirely blank line that terminates them. The (normally blank) line that ends the headers is skipped, but not included in the returned list. If an invalid line is found in the header section, it is skipped, and further lines are processed. The variable self.status is set to the empty string if all went well, otherwise it is an error message. The variable self.headers is a completely uninterpreted list of lines contained in the header (so printing them will reproduce the header exactly as it appears in the file). If multiple header fields with the same name occur, they are combined according to the rules in RFC 2616 sec 4.2: Appending each subsequent field-value to the first, each separated by a comma. The order in which header fields with the same field-name are received is significant to the interpretation of the combined field value. """ # XXX The implementation overrides the readheaders() method of # rfc822.Message. The base class design isn't amenable to # customized behavior here so the method here is a copy of the # base class code with a few small changes. self.dict = {} self.unixfrom = '' self.headers = hlist = [] self.status = '' headerseen = "" firstline = 1 tell = None if not hasattr(self.fp, 'unread') and self.seekable: tell = self.fp.tell while True: if len(hlist) > _MAXHEADERS: raise HTTPException("got more than %d headers" % _MAXHEADERS) if tell: try: tell() except IOError: tell = None self.seekable = 0 line = self.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("header line") if not line: self.status = 'EOF in headers' break # Skip unix From name time lines if firstline and line.startswith('From '): self.unixfrom = self.unixfrom + line continue firstline = 0 if headerseen and line[0] in ' \t': # XXX Not sure if continuation lines are handled properly # for http and/or for repeating headers # It's a continuation line. hlist.append(line) self.addcontinue(headerseen, line.strip()) continue elif self.iscomment(line): # It's a comment. Ignore it. continue elif self.islast(line): # Note! No pushback here! The delimiter line gets eaten. break headerseen = self.isheader(line) if headerseen: # It's a legal header line, save it. hlist.append(line) self.addheader(headerseen, line[len(headerseen)+1:].strip()) elif headerseen is not None: # An empty header name. These aren't allowed in HTTP, but it's # probably a benign mistake. Don't add the header, just keep # going. pass else: # It's not a header line; skip it and try the next line. self.status = 'Non-header line where header expected' def _read_headers(fp): """Reads potential header lines into a list from a file pointer. Length of line is limited by _MAXLINE, and number of headers is limited by _MAXHEADERS. """ headers = [] while True: line = fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("header line") headers.append(line) if len(headers) > _MAXHEADERS: raise HTTPException("got more than %d headers" % _MAXHEADERS) if line in (b'\r\n', b'\n', b''): break return headers class HTTPResponse: # strict: If true, raise BadStatusLine if the status line can't be # parsed as a valid HTTP/1.0 or 1.1 status line. By default it is # false because it prevents clients from talking to HTTP/0.9 # servers. Note that a response with a sufficiently corrupted # status line will look like an HTTP/0.9 response. # See RFC 2616 sec 19.6 and RFC 1945 sec 6 for details. def __init__(self, sock, debuglevel=0, strict=0, method=None, buffering=False): if buffering: # The caller won't be using any sock.recv() calls, so buffering # is fine and recommended for performance. self.fp = sock.makefile('rb') else: # The buffer size is specified as zero, because the headers of # the response are read with readline(). If the reads were # buffered the readline() calls could consume some of the # response, which make be read via a recv() on the underlying # socket. self.fp = sock.makefile('rb', 0) self.debuglevel = debuglevel self.strict = strict self._method = method self.msg = None # from the Status-Line of the response self.version = _UNKNOWN # HTTP-Version self.status = _UNKNOWN # Status-Code self.reason = _UNKNOWN # Reason-Phrase self.chunked = _UNKNOWN # is "chunked" being used? self.chunk_left = _UNKNOWN # bytes left to read in current chunk self.length = _UNKNOWN # number of bytes left in response self.will_close = _UNKNOWN # conn will close at end of response def _read_status(self): # Initialize with Simple-Response defaults line = self.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("header line") if self.debuglevel > 0: print "reply:", repr(line) if not line: # Presumably, the server closed the connection before # sending a valid response. raise BadStatusLine("No status line received - the server has closed the connection") try: [version, status, reason] = line.split(None, 2) except ValueError: try: [version, status] = line.split(None, 1) reason = "" except ValueError: # empty version will cause next test to fail and status # will be treated as 0.9 response. version = "" if not version.startswith('HTTP/'): if self.strict: self.close() raise BadStatusLine(line) else: # assume it's a Simple-Response from an 0.9 server self.fp = LineAndFileWrapper(line, self.fp) return "HTTP/0.9", 200, "" # The status code is a three-digit number try: status = int(status) if status < 100 or status > 999: raise BadStatusLine(line) except ValueError: raise BadStatusLine(line) return version, status, reason def begin(self): if self.msg is not None: # we've already started reading the response return # read until we get a non-100 response while True: version, status, reason = self._read_status() if status != CONTINUE: break # skip the header from the 100 response skipped_headers = _read_headers(self.fp) if self.debuglevel > 0: print("headers:", skipped_headers) del skipped_headers self.status = status self.reason = reason.strip() if version == 'HTTP/1.0': self.version = 10 elif version.startswith('HTTP/1.'): self.version = 11 # use HTTP/1.1 code for HTTP/1.x where x>=1 elif version == 'HTTP/0.9': self.version = 9 else: raise UnknownProtocol(version) if self.version == 9: self.length = None self.chunked = 0 self.will_close = 1 self.msg = HTTPMessage(StringIO()) return self.msg = HTTPMessage(self.fp, 0) if self.debuglevel > 0: for hdr in self.msg.headers: print "header:", hdr, # don't let the msg keep an fp self.msg.fp = None # are we using the chunked-style of transfer encoding? tr_enc = self.msg.getheader('transfer-encoding') if tr_enc and tr_enc.lower() == "chunked": self.chunked = 1 self.chunk_left = None else: self.chunked = 0 # will the connection close at the end of the response? self.will_close = self._check_close() # do we have a Content-Length? # NOTE: RFC 2616, S4.4, #3 says we ignore this if tr_enc is "chunked" length = self.msg.getheader('content-length') if length and not self.chunked: try: self.length = int(length) except ValueError: self.length = None else: if self.length < 0: # ignore nonsensical negative lengths self.length = None else: self.length = None # does the body have a fixed length? (of zero) if (status == NO_CONTENT or status == NOT_MODIFIED or 100 <= status < 200 or # 1xx codes self._method == 'HEAD'): self.length = 0 # if the connection remains open, and we aren't using chunked, and # a content-length was not provided, then assume that the connection # WILL close. if not self.will_close and \ not self.chunked and \ self.length is None: self.will_close = 1 def _check_close(self): conn = self.msg.getheader('connection') if self.version == 11: # An HTTP/1.1 proxy is assumed to stay open unless # explicitly closed. conn = self.msg.getheader('connection') if conn and "close" in conn.lower(): return True return False # Some HTTP/1.0 implementations have support for persistent # connections, using rules different than HTTP/1.1. # For older HTTP, Keep-Alive indicates persistent connection. if self.msg.getheader('keep-alive'): return False # At least Akamai returns a "Connection: Keep-Alive" header, # which was supposed to be sent by the client. if conn and "keep-alive" in conn.lower(): return False # Proxy-Connection is a netscape hack. pconn = self.msg.getheader('proxy-connection') if pconn and "keep-alive" in pconn.lower(): return False # otherwise, assume it will close return True def close(self): fp = self.fp if fp: self.fp = None fp.close() def isclosed(self): # NOTE: it is possible that we will not ever call self.close(). This # case occurs when will_close is TRUE, length is None, and we # read up to the last byte, but NOT past it. # # IMPLIES: if will_close is FALSE, then self.close() will ALWAYS be # called, meaning self.isclosed() is meaningful. return self.fp is None # XXX It would be nice to have readline and __iter__ for this, too. def read(self, amt=None): if self.fp is None: return '' if self._method == 'HEAD': self.close() return '' if self.chunked: return self._read_chunked(amt) if amt is None: # unbounded read if self.length is None: s = self.fp.read() else: try: s = self._safe_read(self.length) except IncompleteRead: self.close() raise self.length = 0 self.close() # we read everything return s if self.length is not None: if amt > self.length: # clip the read to the "end of response" amt = self.length # we do not use _safe_read() here because this may be a .will_close # connection, and the user is reading more bytes than will be provided # (for example, reading in 1k chunks) s = self.fp.read(amt) if not s and amt: # Ideally, we would raise IncompleteRead if the content-length # wasn't satisfied, but it might break compatibility. self.close() if self.length is not None: self.length -= len(s) if not self.length: self.close() return s def _read_chunked(self, amt): assert self.chunked != _UNKNOWN chunk_left = self.chunk_left value = [] while True: if chunk_left is None: line = self.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("chunk size") i = line.find(';') if i >= 0: line = line[:i] # strip chunk-extensions try: chunk_left = int(line, 16) except ValueError: # close the connection as protocol synchronisation is # probably lost self.close() raise IncompleteRead(''.join(value)) if chunk_left == 0: break if amt is None: value.append(self._safe_read(chunk_left)) elif amt < chunk_left: value.append(self._safe_read(amt)) self.chunk_left = chunk_left - amt return ''.join(value) elif amt == chunk_left: value.append(self._safe_read(amt)) self._safe_read(2) # toss the CRLF at the end of the chunk self.chunk_left = None return ''.join(value) else: value.append(self._safe_read(chunk_left)) amt -= chunk_left # we read the whole chunk, get another self._safe_read(2) # toss the CRLF at the end of the chunk chunk_left = None # read and discard trailer up to the CRLF terminator ### note: we shouldn't have any trailers! while True: line = self.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("trailer line") if not line: # a vanishingly small number of sites EOF without # sending the trailer break if line == '\r\n': break # we read everything; close the "file" self.close() return ''.join(value) def _safe_read(self, amt): """Read the number of bytes requested, compensating for partial reads. Normally, we have a blocking socket, but a read() can be interrupted by a signal (resulting in a partial read). Note that we cannot distinguish between EOF and an interrupt when zero bytes have been read. IncompleteRead() will be raised in this situation. This function should be used when <amt> bytes "should" be present for reading. If the bytes are truly not available (due to EOF), then the IncompleteRead exception can be used to detect the problem. """ # NOTE(gps): As of svn r74426 socket._fileobject.read(x) will never # return less than x bytes unless EOF is encountered. It now handles # signal interruptions (socket.error EINTR) internally. This code # never caught that exception anyways. It seems largely pointless. # self.fp.read(amt) will work fine. s = [] while amt > 0: chunk = self.fp.read(min(amt, MAXAMOUNT)) if not chunk: raise IncompleteRead(''.join(s), amt) s.append(chunk) amt -= len(chunk) return ''.join(s) def fileno(self): return self.fp.fileno() def getheader(self, name, default=None): if self.msg is None: raise ResponseNotReady() return self.msg.getheader(name, default) def getheaders(self): """Return list of (header, value) tuples.""" if self.msg is None: raise ResponseNotReady() return self.msg.items() class HTTPConnection: _http_vsn = 11 _http_vsn_str = 'HTTP/1.1' response_class = HTTPResponse default_port = HTTP_PORT auto_open = 1 debuglevel = 0 strict = 0 def __init__(self, host, port=None, strict=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT, source_address=None): self.timeout = timeout self.source_address = source_address self.sock = None self._buffer = [] self.__response = None self.__state = _CS_IDLE self._method = None self._tunnel_host = None self._tunnel_port = None self._tunnel_headers = {} if strict is not None: self.strict = strict (self.host, self.port) = self._get_hostport(host, port) self._validate_host(self.host) # This is stored as an instance variable to allow unittests # to replace with a suitable mock self._create_connection = socket.create_connection def set_tunnel(self, host, port=None, headers=None): """ Set up host and port for HTTP CONNECT tunnelling. In a connection that uses HTTP Connect tunneling, the host passed to the constructor is used as proxy server that relays all communication to the endpoint passed to set_tunnel. This is done by sending a HTTP CONNECT request to the proxy server when the connection is established. This method must be called before the HTTP connection has been established. The headers argument should be a mapping of extra HTTP headers to send with the CONNECT request. """ # Verify if this is required. if self.sock: raise RuntimeError("Can't setup tunnel for established connection.") self._tunnel_host, self._tunnel_port = self._get_hostport(host, port) if headers: self._tunnel_headers = headers else: self._tunnel_headers.clear() def _get_hostport(self, host, port): if port is None: i = host.rfind(':') j = host.rfind(']') # ipv6 addresses have [...] if i > j: try: port = int(host[i+1:]) except ValueError: if host[i+1:] == "": # http://foo.com:/ == http://foo.com/ port = self.default_port else: raise InvalidURL("nonnumeric port: '%s'" % host[i+1:]) host = host[:i] else: port = self.default_port if host and host[0] == '[' and host[-1] == ']': host = host[1:-1] return (host, port) def set_debuglevel(self, level): self.debuglevel = level def _tunnel(self): self.send("CONNECT %s:%d HTTP/1.0\r\n" % (self._tunnel_host, self._tunnel_port)) for header, value in self._tunnel_headers.iteritems(): self.send("%s: %s\r\n" % (header, value)) self.send("\r\n") response = self.response_class(self.sock, strict = self.strict, method = self._method) (version, code, message) = response._read_status() if version == "HTTP/0.9": # HTTP/0.9 doesn't support the CONNECT verb, so if httplib has # concluded HTTP/0.9 is being used something has gone wrong. self.close() raise socket.error("Invalid response from tunnel request") if code != 200: self.close() raise socket.error("Tunnel connection failed: %d %s" % (code, message.strip())) while True: line = response.fp.readline(_MAXLINE + 1) if len(line) > _MAXLINE: raise LineTooLong("header line") if not line: # for sites which EOF without sending trailer break if line == '\r\n': break def connect(self): """Connect to the host and port specified in __init__.""" self.sock = self._create_connection((self.host,self.port), self.timeout, self.source_address) if self._tunnel_host: self._tunnel() def close(self): """Close the connection to the HTTP server.""" self.__state = _CS_IDLE try: sock = self.sock if sock: self.sock = None sock.close() # close it manually... there may be other refs finally: response = self.__response if response: self.__response = None response.close() def send(self, data): """Send `data' to the server.""" if self.sock is None: if self.auto_open: self.connect() else: raise NotConnected() if self.debuglevel > 0: print "send:", repr(data) blocksize = 8192 if hasattr(data,'read') and not isinstance(data, array): if self.debuglevel > 0: print "sendIng a read()able" datablock = data.read(blocksize) while datablock: self.sock.sendall(datablock) datablock = data.read(blocksize) else: self.sock.sendall(data) def _output(self, s): """Add a line of output to the current request buffer. Assumes that the line does *not* end with \\r\\n. """ self._buffer.append(s) def _send_output(self, message_body=None): """Send the currently buffered request and clear the buffer. Appends an extra \\r\\n to the buffer. A message_body may be specified, to be appended to the request. """ self._buffer.extend(("", "")) msg = "\r\n".join(self._buffer) del self._buffer[:] # If msg and message_body are sent in a single send() call, # it will avoid performance problems caused by the interaction # between delayed ack and the Nagle algorithm. if isinstance(message_body, str): msg += message_body message_body = None self.send(msg) if message_body is not None: #message_body was not a string (i.e. it is a file) and #we must run the risk of Nagle self.send(message_body) def putrequest(self, method, url, skip_host=0, skip_accept_encoding=0): """Send a request to the server. `method' specifies an HTTP request method, e.g. 'GET'. `url' specifies the object being requested, e.g. '/index.html'. `skip_host' if True does not add automatically a 'Host:' header `skip_accept_encoding' if True does not add automatically an 'Accept-Encoding:' header """ # if a prior response has been completed, then forget about it. if self.__response and self.__response.isclosed(): self.__response = None # in certain cases, we cannot issue another request on this connection. # this occurs when: # 1) we are in the process of sending a request. (_CS_REQ_STARTED) # 2) a response to a previous request has signalled that it is going # to close the connection upon completion. # 3) the headers for the previous response have not been read, thus # we cannot determine whether point (2) is true. (_CS_REQ_SENT) # # if there is no prior response, then we can request at will. # # if point (2) is true, then we will have passed the socket to the # response (effectively meaning, "there is no prior response"), and # will open a new one when a new request is made. # # Note: if a prior response exists, then we *can* start a new request. # We are not allowed to begin fetching the response to this new # request, however, until that prior response is complete. # if self.__state == _CS_IDLE: self.__state = _CS_REQ_STARTED else: raise CannotSendRequest() self._validate_method(method) # Save the method for use later in the response phase self._method = method url = url or '/' self._validate_path(url) request = '%s %s %s' % (method, url, self._http_vsn_str) self._output(self._encode_request(request)) if self._http_vsn == 11: # Issue some standard headers for better HTTP/1.1 compliance if not skip_host: # this header is issued *only* for HTTP/1.1 # connections. more specifically, this means it is # only issued when the client uses the new # HTTPConnection() class. backwards-compat clients # will be using HTTP/1.0 and those clients may be # issuing this header themselves. we should NOT issue # it twice; some web servers (such as Apache) barf # when they see two Host: headers # If we need a non-standard port,include it in the # header. If the request is going through a proxy, # but the host of the actual URL, not the host of the # proxy. netloc = '' if url.startswith('http'): nil, netloc, nil, nil, nil = urlsplit(url) if netloc: try: netloc_enc = netloc.encode("ascii") except UnicodeEncodeError: netloc_enc = netloc.encode("idna") self.putheader('Host', netloc_enc) else: if self._tunnel_host: host = self._tunnel_host port = self._tunnel_port else: host = self.host port = self.port try: host_enc = host.encode("ascii") except UnicodeEncodeError: host_enc = host.encode("idna") # Wrap the IPv6 Host Header with [] (RFC 2732) if host_enc.find(':') >= 0: host_enc = "[" + host_enc + "]" if port == self.default_port: self.putheader('Host', host_enc) else: self.putheader('Host', "%s:%s" % (host_enc, port)) # note: we are assuming that clients will not attempt to set these # headers since *this* library must deal with the # consequences. this also means that when the supporting # libraries are updated to recognize other forms, then this # code should be changed (removed or updated). # we only want a Content-Encoding of "identity" since we don't # support encodings such as x-gzip or x-deflate. if not skip_accept_encoding: self.putheader('Accept-Encoding', 'identity') # we can accept "chunked" Transfer-Encodings, but no others # NOTE: no TE header implies *only* "chunked" #self.putheader('TE', 'chunked') # if TE is supplied in the header, then it must appear in a # Connection header. #self.putheader('Connection', 'TE') else: # For HTTP/1.0, the server will assume "not chunked" pass def _encode_request(self, request): # On Python 2, request is already encoded (default) return request def _validate_method(self, method): """Validate a method name for putrequest.""" # prevent http header injection match = _contains_disallowed_method_pchar_re.search(method) if match: raise ValueError( "method can't contain control characters. %r " "(found at least %r)" % (method, match.group())) def _validate_path(self, url): """Validate a url for putrequest.""" # Prevent CVE-2019-9740. match = _contains_disallowed_url_pchar_re.search(url) if match: msg = ( "URL can't contain control characters. {url!r} " "(found at least {matched!r})" ).format(matched=match.group(), url=url) raise InvalidURL(msg) def _validate_host(self, host): """Validate a host so it doesn't contain control characters.""" # Prevent CVE-2019-18348. match = _contains_disallowed_url_pchar_re.search(host) if match: msg = ( "URL can't contain control characters. {host!r} " "(found at least {matched!r})" ).format(matched=match.group(), host=host) raise InvalidURL(msg) def putheader(self, header, *values): """Send a request header line to the server. For example: h.putheader('Accept', 'text/html') """ if self.__state != _CS_REQ_STARTED: raise CannotSendHeader() header = '%s' % header if not _is_legal_header_name(header): raise ValueError('Invalid header name %r' % (header,)) values = [str(v) for v in values] for one_value in values: if _is_illegal_header_value(one_value): raise ValueError('Invalid header value %r' % (one_value,)) hdr = '%s: %s' % (header, '\r\n\t'.join(values)) self._output(hdr) def endheaders(self, message_body=None): """Indicate that the last header line has been sent to the server. This method sends the request to the server. The optional message_body argument can be used to pass a message body associated with the request. The message body will be sent in the same packet as the message headers if it is string, otherwise it is sent as a separate packet. """ if self.__state == _CS_REQ_STARTED: self.__state = _CS_REQ_SENT else: raise CannotSendHeader() self._send_output(message_body) def request(self, method, url, body=None, headers={}): """Send a complete request to the server.""" self._send_request(method, url, body, headers) def _set_content_length(self, body, method): # Set the content-length based on the body. If the body is "empty", we # set Content-Length: 0 for methods that expect a body (RFC 7230, # Section 3.3.2). If the body is set for other methods, we set the # header provided we can figure out what the length is. thelen = None if body is None and method.upper() in _METHODS_EXPECTING_BODY: thelen = '0' elif body is not None: try: thelen = str(len(body)) except (TypeError, AttributeError): # If this is a file-like object, try to # fstat its file descriptor try: thelen = str(os.fstat(body.fileno()).st_size) except (AttributeError, OSError): # Don't send a length if this failed if self.debuglevel > 0: print "Cannot stat!!" if thelen is not None: self.putheader('Content-Length', thelen) def _send_request(self, method, url, body, headers): # Honor explicitly requested Host: and Accept-Encoding: headers. header_names = dict.fromkeys([k.lower() for k in headers]) skips = {} if 'host' in header_names: skips['skip_host'] = 1 if 'accept-encoding' in header_names: skips['skip_accept_encoding'] = 1 self.putrequest(method, url, **skips) if 'content-length' not in header_names: self._set_content_length(body, method) for hdr, value in headers.iteritems(): self.putheader(hdr, value) self.endheaders(body) def getresponse(self, buffering=False): "Get the response from the server." # if a prior response has been completed, then forget about it. if self.__response and self.__response.isclosed(): self.__response = None # # if a prior response exists, then it must be completed (otherwise, we # cannot read this response's header to determine the connection-close # behavior) # # note: if a prior response existed, but was connection-close, then the # socket and response were made independent of this HTTPConnection # object since a new request requires that we open a whole new # connection # # this means the prior response had one of two states: # 1) will_close: this connection was reset and the prior socket and # response operate independently # 2) persistent: the response was retained and we await its # isclosed() status to become true. # if self.__state != _CS_REQ_SENT or self.__response: raise ResponseNotReady() args = (self.sock,) kwds = {"strict":self.strict, "method":self._method} if self.debuglevel > 0: args += (self.debuglevel,) if buffering: #only add this keyword if non-default, for compatibility with #other response_classes. kwds["buffering"] = True; response = self.response_class(*args, **kwds) try: response.begin() assert response.will_close != _UNKNOWN self.__state = _CS_IDLE if response.will_close: # this effectively passes the connection to the response self.close() else: # remember this, so we can tell when it is complete self.__response = response return response except: response.close() raise class HTTP: "Compatibility class with httplib.py from 1.5." _http_vsn = 10 _http_vsn_str = 'HTTP/1.0' debuglevel = 0 _connection_class = HTTPConnection def __init__(self, host='', port=None, strict=None): "Provide a default host, since the superclass requires one." # some joker passed 0 explicitly, meaning default port if port == 0: port = None # Note that we may pass an empty string as the host; this will raise # an error when we attempt to connect. Presumably, the client code # will call connect before then, with a proper host. self._setup(self._connection_class(host, port, strict)) def _setup(self, conn): self._conn = conn # set up delegation to flesh out interface self.send = conn.send self.putrequest = conn.putrequest self.putheader = conn.putheader self.endheaders = conn.endheaders self.set_debuglevel = conn.set_debuglevel conn._http_vsn = self._http_vsn conn._http_vsn_str = self._http_vsn_str self.file = None def connect(self, host=None, port=None): "Accept arguments to set the host/port, since the superclass doesn't." if host is not None: (self._conn.host, self._conn.port) = self._conn._get_hostport(host, port) self._conn.connect() def getfile(self): "Provide a getfile, since the superclass' does not use this concept." return self.file def getreply(self, buffering=False): """Compat definition since superclass does not define it. Returns a tuple consisting of: - server status code (e.g. '200' if all goes well) - server "reason" corresponding to status code - any RFC822 headers in the response from the server """ try: if not buffering: response = self._conn.getresponse() else: #only add this keyword if non-default for compatibility #with other connection classes response = self._conn.getresponse(buffering) except BadStatusLine, e: ### hmm. if getresponse() ever closes the socket on a bad request, ### then we are going to have problems with self.sock ### should we keep this behavior? do people use it? # keep the socket open (as a file), and return it self.file = self._conn.sock.makefile('rb', 0) # close our socket -- we want to restart after any protocol error self.close() self.headers = None return -1, e.line, None self.headers = response.msg self.file = response.fp return response.status, response.reason, response.msg def close(self): self._conn.close() # note that self.file == response.fp, which gets closed by the # superclass. just clear the object ref here. ### hmm. messy. if status==-1, then self.file is owned by us. ### well... we aren't explicitly closing, but losing this ref will ### do it self.file = None try: import ssl except ImportError: pass else: class HTTPSConnection(HTTPConnection): "This class allows communication via SSL." default_port = HTTPS_PORT def __init__(self, host, port=None, key_file=None, cert_file=None, strict=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT, source_address=None, context=None): HTTPConnection.__init__(self, host, port, strict, timeout, source_address) self.key_file = key_file self.cert_file = cert_file if context is None: context = ssl._create_default_https_context() if key_file or cert_file: context.load_cert_chain(cert_file, key_file) self._context = context def connect(self): "Connect to a host on a given (SSL) port." HTTPConnection.connect(self) if self._tunnel_host: server_hostname = self._tunnel_host else: server_hostname = self.host self.sock = self._context.wrap_socket(self.sock, server_hostname=server_hostname) __all__.append("HTTPSConnection") class HTTPS(HTTP): """Compatibility with 1.5 httplib interface Python 1.5.2 did not have an HTTPS class, but it defined an interface for sending http requests that is also useful for https. """ _connection_class = HTTPSConnection def __init__(self, host='', port=None, key_file=None, cert_file=None, strict=None, context=None): # provide a default host, pass the X509 cert info # urf. compensate for bad input. if port == 0: port = None self._setup(self._connection_class(host, port, key_file, cert_file, strict, context=context)) # we never actually use these for anything, but we keep them # here for compatibility with post-1.5.2 CVS. self.key_file = key_file self.cert_file = cert_file def FakeSocket (sock, sslobj): warnings.warn("FakeSocket is deprecated, and won't be in 3.x. " + "Use the result of ssl.wrap_socket() directly instead.", DeprecationWarning, stacklevel=2) return sslobj class HTTPException(Exception): # Subclasses that define an __init__ must call Exception.__init__ # or define self.args. Otherwise, str() will fail. pass class NotConnected(HTTPException): pass class InvalidURL(HTTPException): pass class UnknownProtocol(HTTPException): def __init__(self, version): self.args = version, self.version = version class UnknownTransferEncoding(HTTPException): pass class UnimplementedFileMode(HTTPException): pass class IncompleteRead(HTTPException): def __init__(self, partial, expected=None): self.args = partial, self.partial = partial self.expected = expected def __repr__(self): if self.expected is not None: e = ', %i more expected' % self.expected else: e = '' return 'IncompleteRead(%i bytes read%s)' % (len(self.partial), e) def __str__(self): return repr(self) class ImproperConnectionState(HTTPException): pass class CannotSendRequest(ImproperConnectionState): pass class CannotSendHeader(ImproperConnectionState): pass class ResponseNotReady(ImproperConnectionState): pass class BadStatusLine(HTTPException): def __init__(self, line): if not line: line = repr(line) self.args = line, self.line = line class LineTooLong(HTTPException): def __init__(self, line_type): HTTPException.__init__(self, "got more than %d bytes when reading %s" % (_MAXLINE, line_type)) # for backwards compatibility error = HTTPException class LineAndFileWrapper: """A limited file-like object for HTTP/0.9 responses.""" # The status-line parsing code calls readline(), which normally # get the HTTP status line. For a 0.9 response, however, this is # actually the first line of the body! Clients need to get a # readable file object that contains that line. def __init__(self, line, file): self._line = line self._file = file self._line_consumed = 0 self._line_offset = 0 self._line_left = len(line) def __getattr__(self, attr): return getattr(self._file, attr) def _done(self): # called when the last byte is read from the line. After the # call, all read methods are delegated to the underlying file # object. self._line_consumed = 1 self.read = self._file.read self.readline = self._file.readline self.readlines = self._file.readlines def read(self, amt=None): if self._line_consumed: return self._file.read(amt) assert self._line_left if amt is None or amt > self._line_left: s = self._line[self._line_offset:] self._done() if amt is None: return s + self._file.read() else: return s + self._file.read(amt - len(s)) else: assert amt <= self._line_left i = self._line_offset j = i + amt s = self._line[i:j] self._line_offset = j self._line_left -= amt if self._line_left == 0: self._done() return s def readline(self): if self._line_consumed: return self._file.readline() assert self._line_left s = self._line[self._line_offset:] self._done() return s def readlines(self, size=None): if self._line_consumed: return self._file.readlines(size) assert self._line_left L = [self._line[self._line_offset:]] self._done() if size is None: return L + self._file.readlines() else: return L + self._file.readlines(size)
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