class DSLink:
"""
Base DSLink class which creates the node structure,
subscription/stream manager, and connects to the broker.
"""
def __init__(self, config):
"""
Construct for DSLink.
:param config: Configuration object.
"""
self.active = False
self.needs_auth = False
# DSLink Configuration
self.config = config
self.server_config = None
# Logger setup
self.logger = self.create_logger("DSLink", self.config.log_level)
self.logger.info("Starting DSLink")
# Requester and Responder setup
if self.config.requester:
self.requester = Requester(self)
if self.config.responder:
self.responder = Responder(self)
self.responder.start()
# DSLink setup
self.keypair = Keypair(self.config.keypair_path)
self.handshake = Handshake(self, self.keypair)
self.handshake.run_handshake()
self.dsid = self.handshake.get_dsid()
# Connection setup
self.wsp = None
self.websocket = WebSocket(self)
self.call_later(1, self.start)
self.logger.info("Started DSLink")
self.logger.debug("Starting reactor")
reactor.run()
def start(self):
"""
Called once the DSLink is initialized and connected.
Override this rather than the constructor.
"""
pass
# noinspection PyMethodMayBeStatic
def get_default_nodes(self, super_root):
"""
Create the default Node structure in this, override it.
:param super_root: Super Root.
:return: Super Root with default Node structure.
"""
return super_root
def get_auth(self):
"""
Get auth parameter for connection.
:return: Auth parameter.
"""
auth = str(self.server_config["salt"]) + self.shared_secret
auth = base64.urlsafe_b64encode(hashlib.sha256(auth).digest()).decode("utf-8").replace("=", "")
return auth
def get_url(self):
"""
Get full WebSocket URL.
:return: WebSocket URL.
"""
websocket_uri = self.config.broker[:-5].replace("http", "ws") + "/ws?dsId=%s" % self.dsid
if self.needs_auth:
websocket_uri += "&auth=%s" % self.get_auth()
if self.config.token is not None:
websocket_uri += "&token=%s" % self.config.token
url = urlparse(websocket_uri)
if url.port is None:
port = 80
else:
port = url.port
return websocket_uri, url, port
@staticmethod
def create_logger(name, log_level=logging.INFO):
"""
Create a logger with the specified name.
:param name: Logger name.
:param log_level: Output Logger level.
:return: Logger instance.
"""
# Logger setup
formatter = logging.Formatter('%(asctime)s %(name)s %(levelname)s %(message)s')
ch = logging.StreamHandler()
ch.setFormatter(formatter)
ch.setLevel(log_level)
logger = logging.getLogger(name)
logger.setLevel(log_level)
logger.addHandler(ch)
return logger
@staticmethod
def add_padding(string):
"""
Add padding to a URL safe base64 string.
:param string:
:return:
"""
while len(string) % 4 != 0:
string += "="
return string
@staticmethod
def call_later(delay, call, *args, **kw):
"""
Call function later.
:param delay: Seconds to delay.
:param call: Method to call.
:param args: Arguments.
:return: DelayedCall instance.
"""
return reactor.callLater(delay, call, *args, **kw)