better sketch of transit-client API

bin/receive_file.py

@@ -12,23 +12,28 @@ APPID = "lothar.com/wormhole/file-xfer"
 transit_receiver = TransitReceiver()
 direct_hints = transit_receiver.get_direct_hints()
 
-data = json.dumps({"direct_connection_hints": direct_hints,
-                   }).encode("utf-8")
-r = Receiver(APPID, data)
+mydata = json.dumps({
+    "transit": {
+        "direct_connection_hints": direct_hints,
+        },
+    }).encode("utf-8")
+r = Receiver(APPID, mydata)
 r.set_code(r.input_code("Enter receive-text wormhole code: "))
 
-them_bytes = r.get_data()
-them_d = json.loads(them_bytes.decode("utf-8"))
-print("them: %r" % (them_d,))
+data = json.loads(r.get_data().decode("utf-8"))
+print("their data: %r" % (data,))
 
-xfer_key = unhexlify(them_d["xfer_key"].encode("ascii"))
-filename = os.path.basename(them_d["filename"]) # unicode
-filesize = them_d["filesize"]
+file_data = data["file"]
+xfer_key = unhexlify(file_data["key"].encode("ascii"))
+filename = os.path.basename(file_data["filename"]) # unicode
+filesize = file_data["filesize"]
 
 # now receive the rest of the owl
-transit_receiver.add_sender_direct_hints(them_d["direct_connection_hints"])
-transit_receiver.add_sender_relay_hints(them_d["relay_connection_hints"])
-transit_receiver.establish_connection(IDS)
+tdata = data["transit"]
+transit_receiver.set_transit_key(tdata["key"])
+transit_receiver.add_sender_direct_hints(tdata["direct_connection_hints"])
+transit_receiver.add_sender_relay_hints(tdata["relay_connection_hints"])
+transit_receiver.establish_connection()
 encrypted = transit_receiver.receive()
 
 decrypted = SecretBox(xfer_key).decrypt(encrypted)

bin/send_file.py

@@ -2,7 +2,6 @@ from __future__ import print_function
 import os, sys, json
 from binascii import hexlify
 from nacl.secret import SecretBox
-from nacl import utils
 from wormhole.blocking.transcribe import Initiator
 from wormhole.blocking.transit import TransitSender
 
@@ -11,17 +10,24 @@ APPID = "lothar.com/wormhole/file-xfer"
 # we're sending
 filename = sys.argv[1]
 assert os.path.isfile(filename)
-xfer_key = utils.random(SecretBox.KEY_SIZE)
+xfer_key = os.urandom(SecretBox.KEY_SIZE)
 transit_sender = TransitSender()
+transit_key = transit_sender.get_transit_key()
 direct_hints = transit_sender.get_direct_hints()
 relay_hints = transit_sender.get_relay_hints()
 
-data = json.dumps({"xfer_key": hexlify(xfer_key),
-                   "filename": os.path.basename(filename),
-                   "filesize": os.stat(filename).st_size,
-                   "direct_connection_hints": direct_hints,
-                   "relay_connection_hints": relay_hints,
-                   }).encode("utf-8")
+data = json.dumps({
+    "file": {
+        "key": hexlify(xfer_key),
+        "filename": os.path.basename(filename),
+        "filesize": os.stat(filename).st_size,
+        },
+    "transit": {
+        "key": hexlify(transit_key),
+        "direct_connection_hints": direct_hints,
+        "relay_connection_hints": relay_hints,
+        },
+    }).encode("utf-8")
 
 i = Initiator(APPID, data)
 code = i.get_code()
@@ -39,7 +45,7 @@ nonce = utils.random(SecretBox.NONCE_SIZE)
 encrypted = box.encrypt(plaintext, nonce)
 
 transit_sender.add_receiver_hints(them_d["direct_connection_hints"])
-transit_sender.establish_connection(IDS)
+transit_sender.establish_connection()
 transit_sender.write(encrypted)
 transit_sender.close()
 

src/wormhole/blocking/transit.py

@@ -1,7 +1,11 @@
+import os
+from ..util import ipaddrs
 
 class TransitSender:
-    def __init__(self, IDS):
-        pass
+    def __init__(self):
+        self.key = os.urandom(32)
+    def get_transit_key(self):
+        return self.key
     def get_direct_hints(self):
         pass
     def get_relay_hints(self):
@@ -16,10 +20,12 @@ class TransitSender:
         pass
 
 class TransitReceiver:
-    def __init__(self, IDS):
+    def __init__(self):
         pass
     def get_direct_hints(self):
         pass
+    def set_transit_key(self, key):
+        self.key = key
     def add_sender_direct_hints(self, hints):
         self.sender_direct_hints = hints
     def add_sender_relay_hints(self, hints):