Fixes #368. random-peer and not-self tx broadcast.

Prior to this commit, users setting the POLICY config
option `tx_broadcast` to anything other than `self` would
cause a crash after the merge of #536 due to a bin/hex
conversion failure (before this merge, the tx would simply
fail to broadcast).
This commit adds a `JMTXBroadcast` AMP command so that makers
can send arbitrary transactions from daemon to client, for
broadcast via the blockchain interface. This allows the
existing code in `taker.push()` to function correctly, after
fixing the bin/hex conversion bug. Hence users can now select
`random-peer` or `not-self` and the transaction will be
broadcast as expected according to the comments, and the
WalletService will react to the broadcast just as it does
currently for self-broadcast.
Note that this change will be ineffective if the counterparties
do not support it; the transaction will simply remain un-broadcast.

jmbase/jmbase/commands.py

@@ -220,3 +220,11 @@ class JMTXReceived(JMCommand):
     arguments = [(b'nick', Unicode()),
                  (b'txhex', Unicode()),
                  (b'offer', Unicode())]
+
+class JMTXBroadcast(JMCommand):
+    """ Accept a bitcoin transaction
+    sent over the wire by a counterparty
+    and relay it to the client for network
+    broadcast.
+    """
+    arguments = [(b'txhex', Unicode())]

jmbase/test/test_commands.py

@@ -111,7 +111,9 @@ class JMTestServerProtocol(JMBaseProtocol):
                                         hashlen=4,
                                         max_encoded=5,
                                         hostid="hostid2")
-        self.defaultCallbacks(d3)        
+        self.defaultCallbacks(d3)
+        d4 = self.callRemote(JMTXBroadcast, txhex="deadbeef")
+        self.defaultCallbacks(d4)
         return {'accepted': True}
             
 
@@ -216,6 +218,11 @@ class JMTestClientProtocol(JMBaseProtocol):
         self.defaultCallbacks(d)
         return {'accepted': True}
 
+    @JMTXBroadcast.responder
+    def on_JM_TX_BROADCAST(self, txhex):
+        show_receipt("JMTXBROADCAST", txhex)
+        return {"accepted": True}
+
 class JMTestClientProtocolFactory(protocol.ClientFactory):
     protocol = JMTestClientProtocol
 

jmclient/jmclient/client_protocol.py

@@ -301,6 +301,22 @@ class JMMakerClientProtocol(JMClientProtocol):
             self.defaultCallbacks(d)
         return {"accepted": True}
 
+    @commands.JMTXBroadcast.responder
+    def on_JM_TX_BROADCAST(self, txhex):
+        """ Makers have no issue broadcasting anything,
+        so only need to prevent crashes.
+        Note in particular we don't check the return value,
+        since the transaction being accepted or not is not
+        our (maker)'s concern.
+        """
+        try:
+            txbin = hextobin(txhex)
+            jm_single().bc_interface.pushtx(txbin)
+        except:
+            jlog.info("We received an invalid transaction broadcast "
+                      "request: " + txhex)
+        return {"accepted": True}
+
     def tx_match(self, txd):
         for k,v in self.finalized_offers.items():
             # Tx considered defined by its output set

jmclient/jmclient/taker.py

@@ -830,8 +830,7 @@ class Taker(object):
             self.on_finished_callback(False, fromtx=True)
         else:
             if nick_to_use:
-                # TODO option not currently functional
-                return (nick_to_use, self.latest_tx.serialize())
+                return (nick_to_use, bintohex(self.latest_tx.serialize()))
         #if push was not successful, return None
 
     def self_sign_and_push(self):

jmdaemon/jmdaemon/daemon_protocol.py

@@ -9,6 +9,7 @@ from .protocol import (COMMAND_PREFIX, ORDER_KEYS, NICK_HASH_LENGTH,
                        COMMITMENT_PREFIXES)
 from .irc import IRCMessageChannel
 
+from jmbase import hextobin
 from jmbase.commands import *
 from twisted.protocols import amp
 from twisted.internet import reactor, ssl
@@ -432,9 +433,16 @@ class JMDaemonServerProtocol(amp.AMP, OrderbookWatch):
 
     @maker_only
     def on_push_tx(self, nick, txhex):
-        """Not yet implemented; ignore rather than raise.
+        """Broadcast unquestioningly, except checking
+        hex format.
 	"""
-        log.msg('received pushtx message, ignoring, TODO')
+        try:
+            dummy = hextobin(txhex)
+        except:
+            return
+        d = self.callRemote(JMTXBroadcast,
+                            txhex=txhex)
+        self.defaultCallbacks(d)
 
     @maker_only
     def on_seen_tx(self, nick, txhex):