def _skip_spaces(self):
# 4.1 35. read a byte from the server
while True:
ch = _receive_bytes(self._socket, 1)
if ch == ' ': # 0x20
continue
return ch
def _read_fields(self):
# 4.1 32. let /fields/ be a list of name-value pairs, initially empty.
fields = {}
while True: # "Field"
# 4.1 33. let /name/ and /value/ be empty byte arrays
name = ''
value = ''
# 4.1 34. read /name/
name = self._read_name()
if name is None:
break
# 4.1 35. read spaces
# TODO(tyoshino): Skip only one space as described in the spec.
ch = self._skip_spaces()
# 4.1 36. read /value/
value = self._read_value(ch)
# 4.1 37. read a byte from the server
ch = _receive_bytes(self._socket, 1)
if ch != '\n': # 0x0A
raise ClientHandshakeError(
'Expected LF but found %r while reading value %r for '
'header %r' % (ch, value, name))
self._logger.debug('Received %r header', name)
# 4.1 38. append an entry to the /fields/ list that has the name
# given by the string obtained by interpreting the /name/ byte
# array as a UTF-8 stream and the value given by the string
# obtained by interpreting the /value/ byte array as a UTF-8 byte
# stream.
fields.setdefault(name, []).append(value)
# 4.1 39. return to the "Field" step above
return fields
def _read_value(self, ch):
# 4.1 33. let /value/ be empty byte arrays
value = ''
# 4.1 36. read a byte from server.
while True:
if ch == '\r': # 0x0D
return value
elif ch == '\n': # 0x0A
raise ClientHandshakeError(
'Unexpected LF when reading header value %r' % value)
else:
value += ch
ch = _receive_bytes(self._socket, 1)
def _read_name(self):
# 4.1 33. let /name/ be empty byte arrays
name = ''
while True:
# 4.1 34. read a byte from the server
ch = _receive_bytes(self._socket, 1)
if ch == '\r': # 0x0D
return None
elif ch == '\n': # 0x0A
raise ClientHandshakeError(
'Unexpected LF when reading header name %r' % name)
elif ch == ':': # 0x3A
return name
elif ch >= 'A' and ch <= 'Z': # Range 0x31 to 0x5A
ch = chr(ord(ch) + 0x20)
name += ch
else:
name += ch
def handshake(self):
"""Performs opening handshake on the specified socket.
Raises:
ClientHandshakeError: handshake failed.
"""
request_line = _build_method_line(self._options.get('resource'))
self._logger.debug('Client\'s opening handshake Request-Line: %r',
request_line)
self._socket.sendall(request_line)
fields = []
fields.append(_format_host_header(
self._options.get('server_host'),
int(self._options.get('server_port')),
self._options.get('use_tls')=='True'))
fields.append(_UPGRADE_HEADER)
fields.append(_CONNECTION_HEADER)
if self._options.get('origin') is not None:
if self._options.get('protocol_version') == _PROTOCOL_VERSION_HYBI08:
fields.append(_origin_header(
common.SEC_WEBSOCKET_ORIGIN_HEADER,
self._options.get('origin')))
else:
fields.append(_origin_header(common.ORIGIN_HEADER,
self._options.get('origin')))
original_key = os.urandom(16)
self._key = base64.b64encode(original_key)
self._logger.debug(
'%s: %r (%s)',
common.SEC_WEBSOCKET_KEY_HEADER,
self._key,
util.hexify(original_key))
fields.append(
'%s: %s\r\n' % (common.SEC_WEBSOCKET_KEY_HEADER, self._key))
if int(self._options.get('version_header')) > 0:
fields.append('%s: %d\r\n' % (common.SEC_WEBSOCKET_VERSION_HEADER,
int(self._options.get('version_header'))))
else:
fields.append('%s: %d\r\n' % (common.SEC_WEBSOCKET_VERSION_HEADER,
common.VERSION_HYBI_LATEST))
extensions_to_request = []
if self._options.get('deflate_stream') == 'True':
extensions_to_request.append(
common.ExtensionParameter(
common.DEFLATE_STREAM_EXTENSION))
if self._options.get('deflate_frame') == 'True':
extensions_to_request.append(
common.ExtensionParameter(common.DEFLATE_FRAME_EXTENSION))
if len(extensions_to_request) != 0:
fields.append(
'%s: %s\r\n' %
(common.SEC_WEBSOCKET_EXTENSIONS_HEADER,
common.format_extensions(extensions_to_request)))
for field in fields:
self._socket.sendall(field)
self._socket.sendall('\r\n')
self._logger.debug('Sent client\'s opening handshake headers: %r',
fields)
self._logger.debug('Start reading Status-Line')
status_line = ''
while True:
ch = _receive_bytes(self._socket, 1)
status_line += ch
if ch == '\n':
break
m = re.match('HTTP/\\d+\.\\d+ (\\d\\d\\d) .*\r\n', status_line)
if m is None:
raise ClientHandshakeError(
'Wrong status line format: %r' % status_line)
status_code = m.group(1)
if status_code != '101':
self._logger.debug('Unexpected status code %s with following '
'headers: %r', status_code, self._read_fields())
raise ClientHandshakeError(
'Expected HTTP status code 101 but found %r' % status_code)
self._logger.debug('Received valid Status-Line')
self._logger.debug('Start reading headers until we see an empty line')
fields = self._read_fields()
ch = _receive_bytes(self._socket, 1)
if ch != '\n': # 0x0A
raise ClientHandshakeError(
'Expected LF but found %r while reading value %r for header '
'name %r' % (ch, value, name))
self._logger.debug('Received an empty line')
self._logger.debug('Server\'s opening handshake headers: %r', fields)
_validate_mandatory_header(
fields,
common.UPGRADE_HEADER,
common.WEBSOCKET_UPGRADE_TYPE,
False)
_validate_mandatory_header(
fields,
common.CONNECTION_HEADER,
common.UPGRADE_CONNECTION_TYPE,
False)
accept = _get_mandatory_header(
fields, common.SEC_WEBSOCKET_ACCEPT_HEADER)
# Validate
try:
binary_accept = base64.b64decode(accept)
except TypeError, e:
raise HandshakeError(
'Illegal value for header %s: %r' %
(common.SEC_WEBSOCKET_ACCEPT_HEADER, accept))
