Content """ Micropython Socket.IO client. """ import ure as re import ujson as json import usocket as socket from ucollections import namedtuple from .protocol import * from .transport import SocketIO URL_RE = re.compile(r'http://([A-Za-z0-9\-\.]+)(?:\:([0-9]+))?(/.+)?') URI = namedtuple('URI', ('hostname', 'port', 'path')) def urlparse(uri): """Parse http:// URLs""" match = URL_RE.match(uri) if match: return URI(match.group(1), int(match.group(2)), match.group(3)) def _connect_http(hostname, port, path): """Stage 1 do the HTTP connection to get our SID""" try: sock = socket.socket() addr = socket.getaddrinfo(hostname, port) sock.connect(addr[0][4]) def send_header(header, *args): sock.write(header % args + '\r\n') send_header(b'GET %s HTTP/1.1', path) send_header(b'Host: %s:%s', hostname, port) send_header(b'') header = sock.readline()[:-2] assert header == b'HTTP/1.1 200 OK', header length = None while header: header = sock.readline()[:-2] if not header: break header, value = header.split(b': ') header = header.lower() if header == b'content-type': assert value == b'application/octet-stream' elif header == b'content-length': length = int(value) assert length data = sock.read(length) return decode_payload(data) finally: sock.close() def connect(uri): """Connect to a socket IO server.""" uri = urlparse(uri) assert uri path = uri.path or '/' + 'socket.io/?EIO=3' # Start a HTTP connection, which will give us an SID to use to upgrade # the websockets connection packets = _connect_http(uri.hostname, uri.port, path) # The first packet should open the connection, # following packets might be initialisation messages for us packet_type, params = next(packets) assert packet_type == PACKET_OPEN params = json.loads(params) assert 'websocket' in params['upgrades'] sid = params['sid'] path += '&sid={}'.format(sid) # Start a websocket and send a probe on it ws_uri = 'ws://{hostname}:{port}{path}&transport=websocket'.format( hostname=uri.hostname, port=uri.port, path=path) socketio = SocketIO(ws_uri, **params) # handle rest of the packets once we're in the main loop @socketio.on('connection') def on_connect(data): for packet_type, data in packets: socketio._handle_packet(packet_type, data) socketio._send_packet(PACKET_PING, 'probe') # Send a follow-up poll _connect_http(uri.hostname, uri.port, path + '&transport=polling') # We should receive an answer to our probe packet = socketio._recv() assert packet == (PACKET_PONG, 'probe') # Upgrade the connection socketio._send_packet(PACKET_UPGRADE) packet = socketio._recv() assert packet == (PACKET_NOOP, '') return socketio