Content """ Websockets client for micropython Based very heavily off https://github.com/aaugustin/websockets/blob/master/websockets/client.py """ import usocket as socket import ubinascii as binascii import urandom as random import ussl from protocol import Websocket, urlparse class WebsocketClient(Websocket): is_client = True def connect(uri): """ Connect a websocket. """ uri = urlparse(uri) assert uri if __debug__: print("open connection %s:%s", uri.hostname, uri.port) sock = socket.socket() addr = socket.getaddrinfo(uri.hostname, uri.port) sock.connect(addr[0][4]) if uri.protocol == 'wss': sock = ussl.wrap_socket(sock) def send_header(header, *args): if __debug__: print(str(header)) sock.write(header % args + '\r\n') # Sec-WebSocket-Key is 16 bytes of random base64 encoded key = binascii.b2a_base64(bytes(random.getrandbits(8) for _ in range(16)))[:-1] send_header(b'GET %s HTTP/1.1', uri.path or '/') send_header(b'Host: %s:%s', uri.hostname, uri.port) send_header(b'Connection: Upgrade') send_header(b'Upgrade: websocket') send_header(b'Sec-WebSocket-Key: %s', key) send_header(b'Sec-WebSocket-Version: 13') send_header(b'Origin: http://{hostname}:{port}'.format( hostname=uri.hostname, port=uri.port) ) send_header(b'') header = sock.readline()[:-2] assert header.startswith(b'HTTP/1.1 101 '), header # We don't (currently) need these headers # FIXME: should we check the return key? while header: if __debug__: print(str(header)) header = sock.readline()[:-2] return WebsocketClient(sock)