socketIO-client/socketIO_client/parsers.py
2015-04-15 07:17:23 -04:00

137 lines
4.3 KiB
Python

import json
from collections import namedtuple
from .symmetries import (
decode_string, encode_string, get_byte, get_character, parse_url)
EngineIOSession = namedtuple('EngineIOSession', [
'id', 'ping_interval', 'ping_timeout', 'transport_upgrades'])
SocketIOData = namedtuple('SocketIOData', ['path', 'ack_id', 'args'])
def parse_host(host, port, resource):
if not host.startswith('http'):
host = 'http://' + host
url_pack = parse_url(host)
is_secure = url_pack.scheme == 'https'
port = port or url_pack.port or (443 if is_secure else 80)
url = '%s:%d%s/%s' % (url_pack.hostname, port, url_pack.path, resource)
return is_secure, url
def parse_engineIO_session(engineIO_packet_data):
d = json.loads(decode_string(engineIO_packet_data))
return EngineIOSession(
id=d['sid'],
ping_interval=d['pingInterval'] / float(1000),
ping_timeout=d['pingTimeout'] / float(1000),
transport_upgrades=d['upgrades'])
def encode_engineIO_content(engineIO_packets):
content = bytearray()
for packet_type, packet_data in engineIO_packets:
packet_text = format_packet_text(packet_type, packet_data)
content.extend(_make_packet_prefix(packet_text) + packet_text)
return content
def decode_engineIO_content(content):
content_index = 0
content_length = len(content)
while content_index < content_length:
try:
content_index, packet_length = _read_packet_length(
content, content_index)
except IndexError:
break
content_index, packet_text = _read_packet_text(
content, content_index, packet_length)
engineIO_packet_type, engineIO_packet_data = parse_packet_text(
packet_text)
yield engineIO_packet_type, engineIO_packet_data
def format_socketIO_packet_data(path=None, ack_id=None, args=None):
socketIO_packet_data = json.dumps(args, ensure_ascii=False) if args else ''
if ack_id is not None:
socketIO_packet_data = str(ack_id) + socketIO_packet_data
if path:
socketIO_packet_data = path + ',' + socketIO_packet_data
return socketIO_packet_data
def parse_socketIO_packet_data(socketIO_packet_data):
data = decode_string(socketIO_packet_data)
if data.startswith('/'):
try:
path, data = data.split(',', 1)
except ValueError:
path = data
data = ''
else:
path = ''
try:
ack_id_string, data = data.split('[', 1)
data = '[' + data
ack_id = int(ack_id_string)
except (ValueError, IndexError):
ack_id = None
try:
args = json.loads(data)
except ValueError:
args = []
return SocketIOData(path=path, ack_id=ack_id, args=args)
def format_packet_text(packet_type, packet_data):
return encode_string(str(packet_type) + packet_data)
def parse_packet_text(packet_text):
packet_type = int(get_character(packet_text, 0))
packet_data = packet_text[1:]
return packet_type, packet_data
def get_namespace_path(socketIO_packet_data):
if not socketIO_packet_data.startswith(b'/'):
return ''
# Loop incrementally in case there is binary data
parts = []
for i in range(len(socketIO_packet_data)):
character = get_character(socketIO_packet_data, i)
if ',' == character:
break
parts.append(character)
return ''.join(parts)
def _make_packet_prefix(packet):
length_string = str(len(packet))
header_digits = bytearray([0])
for i in range(len(length_string)):
header_digits.append(ord(length_string[i]) - 48)
header_digits.append(255)
return header_digits
def _read_packet_length(content, content_index):
while get_byte(content, content_index) != 0:
content_index += 1
content_index += 1
packet_length_string = ''
byte = get_byte(content, content_index)
while byte != 255:
packet_length_string += str(byte)
content_index += 1
byte = get_byte(content, content_index)
return content_index, int(packet_length_string)
def _read_packet_text(content, content_index, packet_length):
while get_byte(content, content_index) == 255:
content_index += 1
packet_text = content[content_index:content_index + packet_length]
return content_index + packet_length, packet_text