Working protobuf passing.

This is barely working, really. In fact, I have an "unused" field in my enum because if I don't prowide it the protobuf serializes down to an empty buffer which breaks all kinds of things.

datajack/__init__.py

@@ -1,12 +1,48 @@
+import enum
+import logging
 import socket
+from typing import Tuple
 import urllib.parse
 
+from proto import control_pb2
+
+LOGGER = logging.getLogger(__name__)
+
+# Uniquely identifies a datajack connection.
+# This indicates the handshake style expected and is used
+# to quickly and easily determine if the client is even speaking the
+# right protocol for the server.
+MAGIC = "e8437140-4347-48cc-a31d-dcdc944ffc15"
+
+# The list of formats supported by this client in descending order of preference
+# This is used for negotiation of the data format that will be used with the server.
+DATA_FORMATS = ",".join([
+	"protobuf",
+	"json",
+])
+
+# The types of access that are allowed with this connection
+class Permissions(enum.Enum):
+	pass
+
+def _parse_netloc(netloc) -> Tuple[str, str, str, int]:
+	app, _, connection = netloc.partition("@")
+	appname, _, version = app.partition(":")
+	host, _, part = connection.partition(":")
+	return appname, version, host, part
+
 class Connection:
 	def __init__(self, uri):
 		parts = urllib.parse.urlparse(uri)
+		print(parts)
 		netloc = parts.netloc
-		self.host, _, self.port = netloc.partition(":")
-		
+		assert parts.scheme == "socket"
+		self.app_name, self.app_version, self.host, self.port = _parse_netloc(netloc)
+		self.namespace = parts.path.lstrip("/")
+		self.public_key = "pretend_key"
+		self.data_format = None
+		self.address = None
+		self.server_key = None
 
 	def __enter__(self):
 		self.connect()
@@ -18,6 +54,7 @@ class Connection:
 	def connect(self):
 		self.socket = socket.socket()
 		self.socket.connect((self.host, int(self.port)))
+		self._handshake()
 
 	def disconnect(self):
 		pass
@@ -25,5 +62,23 @@ class Connection:
 	def send(self, data):
 		self.socket.send(data)
 
+	def _handshake(self):
+		"Handshake with the server, ensure we have all the data we need."
+		fields = [MAGIC, DATA_FORMATS, self.namespace, self.app_name, self.app_version, self.public_key,]
+		cliend_hand = " ".join(fields)
+		self.socket.send(cliend_hand.encode("UTF-8"))
+		server_hand = self.socket.recv(1024)
+		if not server_hand:
+			print("Failed to get server hand")
+		self.data_format, self.address, self.server_key = server_hand.decode("UTF-8").split(" ")
+		LOGGER.info("Data format: %s", self.data_format)
+		command = control_pb2.Command(
+			type=control_pb2.Command.Type.STATUS
+		)
+		to_send = command.SerializeToString()
+		LOGGER.info("Sending '%s'", to_send)
+		self.socket.send(to_send)
+
+
 def connection(uri) -> Connection:
 	return Connection(uri)