Merge PR49: emit pacifier message when key-verification is slow

Closes #29
Closes #49

src/wormhole/cli/cmd_receive.py

@@ -12,6 +12,7 @@ from ..util import (dict_to_bytes, bytes_to_dict, bytes_to_hexstr,
                     estimate_free_space)
 
 APPID = u"lothar.com/wormhole/text-or-file-xfer"
+VERIFY_TIMER = 1
 
 class RespondError(Exception):
     def __init__(self, response):
@@ -75,7 +76,16 @@ class TwistedReceiver:
     @inlineCallbacks
     def _go(self, w):
         yield self._handle_code(w)
-        verifier = yield w.verify()
+        yield w.establish_key()
+        def on_slow_connection():
+            print(u"Key established, waiting for confirmation...",
+                  file=self.args.stderr)
+        notify = self._reactor.callLater(VERIFY_TIMER, on_slow_connection)
+        try:
+            verifier = yield w.verify()
+        finally:
+            if not notify.called:
+                notify.cancel()
         self._show_verifier(verifier)
 
         want_offer = True

src/wormhole/cli/cmd_send.py

@@ -12,6 +12,7 @@ from ..transit import TransitSender
 from ..util import dict_to_bytes, bytes_to_dict, bytes_to_hexstr
 
 APPID = u"lothar.com/wormhole/text-or-file-xfer"
+VERIFY_TIMER = 1
 
 def send(args, reactor=reactor):
     """I implement 'wormhole send'. I return a Deferred that fires with None
@@ -85,8 +86,19 @@ class Sender:
             print(u"Wormhole code is: %s" % code, file=args.stdout)
         print(u"", file=args.stdout)
 
+        yield w.establish_key()
+        def on_slow_connection():
+            print(u"Key established, waiting for confirmation...",
+                  file=args.stderr)
+        notify = self._reactor.callLater(VERIFY_TIMER, on_slow_connection)
+
         # TODO: don't stall on w.verify() unless they want it
-        verifier_bytes = yield w.verify() # this may raise WrongPasswordError
+        try:
+            verifier_bytes = yield w.verify() # this may raise WrongPasswordError
+        finally:
+            if not notify.called:
+                notify.cancel()
+
         if args.verify:
             verifier = bytes_to_hexstr(verifier_bytes)
             while True:

src/wormhole/test/test_scripts.py

@@ -225,7 +225,7 @@ class PregeneratedCode(ServerBase, ScriptsBase, unittest.TestCase):
     @inlineCallbacks
     def _do_test(self, as_subprocess=False,
                  mode="text", addslash=False, override_filename=False):
-        assert mode in ("text", "file", "directory")
+        assert mode in ("text", "file", "directory", "slow-text")
         send_cfg = config("send")
         recv_cfg = config("receive")
         message = "blah blah blah ponies"
@@ -244,7 +244,7 @@ class PregeneratedCode(ServerBase, ScriptsBase, unittest.TestCase):
         receive_dir = self.mktemp()
         os.mkdir(receive_dir)
 
-        if mode == "text":
+        if mode == "text" or mode == "slow-text":
             send_cfg.text = message
 
         elif mode == "file":
@@ -348,8 +348,14 @@ class PregeneratedCode(ServerBase, ScriptsBase, unittest.TestCase):
 
             # The sender might fail, leaving the receiver hanging, or vice
             # versa. Make sure we don't wait on one side exclusively
+            if mode == "slow-text":
+                with mock.patch.object(cmd_send, "VERIFY_TIMER", 0), \
+                      mock.patch.object(cmd_receive, "VERIFY_TIMER", 0):
+                    yield gatherResults([send_d, receive_d], True)
+            else:
+                yield gatherResults([send_d, receive_d], True)
+
 
-            yield gatherResults([send_d, receive_d], True)
             send_stdout = send_cfg.stdout.getvalue()
             send_stderr = send_cfg.stderr.getvalue()
             receive_stdout = recv_cfg.stdout.getvalue()
@@ -361,13 +367,21 @@ class PregeneratedCode(ServerBase, ScriptsBase, unittest.TestCase):
 
         self.maxDiff = None # show full output for assertion failures
 
-        self.failUnlessEqual(send_stderr, "",
+        if mode != "slow-text":
-                             (send_stdout, send_stderr))
+            self.failUnlessEqual(send_stderr, "",
-        self.failUnlessEqual(receive_stderr, "",
+                                 (send_stdout, send_stderr))
-                             (receive_stdout, receive_stderr))
+            self.failUnlessEqual(receive_stderr, "",
+                                 (receive_stdout, receive_stderr))
+        else:
+            self.assertEqual(send_stderr,
+                "Key established, waiting for confirmation...\n",
+                (send_stdout, send_stderr))
+            self.assertEqual(receive_stderr,
+                "Key established, waiting for confirmation...\n",
+                (receive_stdout, receive_stderr))
 
         # check sender
-        if mode == "text":
+        if mode == "text" or mode == "slow-text":
             expected = ("Sending text message ({bytes:d} Bytes){NL}"
                         "On the other computer, please run: "
                         "wormhole receive{NL}"
@@ -401,7 +415,7 @@ class PregeneratedCode(ServerBase, ScriptsBase, unittest.TestCase):
                               .format(NL=NL), send_stdout)
 
         # check receiver
-        if mode == "text":
+        if mode == "text" or mode == "slow-text":
             self.failUnlessEqual(receive_stdout, message+NL)
         elif mode == "file":
             self.failUnlessIn("Receiving file ({size:s}) into: {name}"
@@ -448,6 +462,9 @@ class PregeneratedCode(ServerBase, ScriptsBase, unittest.TestCase):
     def test_directory_override(self):
         return self._do_test(mode="directory", override_filename=True)
 
+    def test_slow_text(self):
+        return self._do_test(mode="slow-text")
+
     @inlineCallbacks
     def _do_test_fail(self, mode, failmode):
         assert mode in ("file", "directory")

src/wormhole/test/test_wormhole.py

@@ -522,6 +522,45 @@ class Basic(unittest.TestCase):
         self.assertEqual(len(pieces), 3) # nameplate plus two words
         self.assert_(re.search(r'^\d+-\w+-\w+$', code), code)
 
+    def _test_establish_key_hook(self, established, before):
+        timing = DebugTiming()
+        w = wormhole._Wormhole(APPID, "relay_url", reactor, None, timing)
+
+        if before:
+            d = w.establish_key()
+
+        if established is True:
+            w._key = b"key"
+        elif established is False:
+            w._key = None
+        else:
+            w._key = b"key"
+            w._error = WelcomeError()
+
+        if not before:
+            d = w.establish_key()
+        else:
+            w._maybe_notify_key()
+
+        if w._key is not None and established is True:
+            self.successResultOf(d)
+        elif established is False:
+            self.assertNot(d.called)
+        else:
+            self.failureResultOf(d)
+
+    def test_establish_key_hook(self):
+        for established in (True, False, "error"):
+            for before in (True, False):
+                self._test_establish_key_hook(established, before)
+
+    def test_establish_key_twice(self):
+        timing = DebugTiming()
+        w = wormhole._Wormhole(APPID, "relay_url", reactor, None, timing)
+        d = w.establish_key()
+        self.assertRaises(InternalError, w.establish_key)
+        del d
+
     # make sure verify() can be called both before and after the verifier is
     # computed
 

src/wormhole/wormhole.py

@@ -237,6 +237,8 @@ class _Wormhole:
         self._flag_need_to_see_mailbox_used = True
         self._flag_need_to_build_msg1 = True
         self._flag_need_to_send_PAKE = True
+        self._establish_key_called = False
+        self._key_waiter = None
         self._key = None
 
         self._version_message = None
@@ -283,6 +285,14 @@ class _Wormhole:
 
     # todo: restore-saved-state entry points
 
+    def establish_key(self):
+        """
+        returns a Deferred that fires when we've established the shared key.
+        When successful, the Deferred fires with a simple `True`, otherwise
+        it fails.
+        """
+        return self._API_establish_key()
+
     def verify(self):
         """Returns a Deferred that fires when we've heard back from the other
         side, and have confirmed that they used the right wormhole code. When
@@ -559,6 +569,7 @@ class _Wormhole:
 
     def _event_established_key(self):
         self._timing.add("key established")
+        self._maybe_notify_key()
 
         # both sides send different (random) version messages
         self._send_version_message()
@@ -569,6 +580,25 @@ class _Wormhole:
         self._maybe_check_version()
         self._maybe_send_phase_messages()
 
+    def _API_establish_key(self):
+        if self._error: return defer.fail(self._error)
+        if self._establish_key_called: raise InternalError
+        self._establish_key_called = True
+        if self._key is not None:
+            return defer.succeed(True)
+        self._key_waiter = defer.Deferred()
+        return self._key_waiter
+
+    def _maybe_notify_key(self):
+        if self._key is None:
+            return
+        if self._error:
+            result = failure.Failure(self._error)
+        else:
+            result = True
+        if self._key_waiter and not self._key_waiter.called:
+            self._key_waiter.callback(result)
+
     def _send_version_message(self):
         # this is encrypted like a normal phase message, and includes a
         # dictionary of version flags to let the other Wormhole know what
@@ -824,6 +854,9 @@ class _Wormhole:
         if self._verifier_waiter and not self._verifier_waiter.called:
             if self.DEBUG: print("EB VW")
             self._verifier_waiter.errback(error)
+        if self._key_waiter and not self._key_waiter.called:
+            if self.DEBUG: print("EB KW")
+            self._key_waiter.errback(error)
         for d in self._receive_waiters.values():
             if self.DEBUG: print("EB RW")
             d.errback(error)