test_lnbase: add test that pays to another local electrum

electrum/lnbase.py

@@ -350,6 +350,11 @@ class Peer(PrintError):
     @log_exceptions
     @handle_disconnect
     async def main_loop(self):
+        """
+        This is used in LNWorker and is necessary so that we don't kill the main
+        task group. It is not merged with _main_loop, so that we can test if the
+        correct exceptions are getting thrown using _main_loop.
+        """
         await self._main_loop()
 
     async def _main_loop(self):

electrum/lnworker.py

@@ -32,7 +32,6 @@ from .lnutil import (Outpoint, calc_short_channel_id, LNPeerAddr,
                      generate_keypair, LnKeyFamily, LOCAL, REMOTE,
                      UnknownPaymentHash, MIN_FINAL_CLTV_EXPIRY_FOR_INVOICE,
                      NUM_MAX_EDGES_IN_PAYMENT_PATH)
-from .lnaddr import lndecode
 from .i18n import _
 from .lnrouter import RouteEdge, is_route_sane_to_use
 
@@ -258,6 +257,15 @@ class LNWorker(PrintError):
         return bh2u(chan.node_id)
 
     def pay(self, invoice, amount_sat=None):
+        """
+        This is not merged with _pay so that we can run the test with
+        one thread only.
+        """
+        addr, peer, coro = self._pay(invoice, amount_sat)
+        fut = asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop)
+        return addr, peer, fut
+
+    def _pay(self, invoice, amount_sat=None):
         addr = lndecode(invoice, expected_hrp=constants.net.SEGWIT_HRP)
         payment_hash = addr.paymenthash
         amount_sat = (addr.amount * COIN) if addr.amount else amount_sat
@@ -279,7 +287,7 @@ class LNWorker(PrintError):
             raise Exception("PathFinder returned path with short_channel_id {} that is not in channel list".format(bh2u(short_channel_id)))
         peer = self.peers[node_id]
         coro = peer.pay(route, chan, amount_msat, payment_hash, addr.get_min_final_cltv_expiry())
-        return addr, peer, asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop)
+        return addr, peer, coro
 
     def _create_route_from_invoice(self, decoded_invoice, amount_msat) -> List[RouteEdge]:
         invoice_pubkey = decoded_invoice.pubkey.serialize()

electrum/tests/test_lnbase.py

@@ -1,16 +1,40 @@
+import unittest
+import asyncio
+import tempfile
+from decimal import Decimal
+import os
+from contextlib import contextmanager
+from collections import defaultdict
+
+from electrum.network import Network
+from electrum.ecc import ECPrivkey
+from electrum import simple_config, lnutil
+from electrum.lnaddr import lnencode, LnAddr, lndecode
+from electrum.bitcoin import COIN, sha256
+from electrum.util import bh2u
+
 from electrum.lnbase import Peer, decode_msg, gen_msg
 from electrum.lnutil import LNPeerAddr, Keypair, privkey_to_pubkey
 from electrum.lnutil import LightningPeerConnectionClosed, RemoteMisbehaving
-from electrum.ecc import ECPrivkey
-from electrum.lnrouter import ChannelDB
-import unittest
-import asyncio
-from electrum import simple_config
-import tempfile
+from electrum.lnrouter import ChannelDB, LNPathFinder
+from electrum.lnworker import LNWorker
+
 from .test_lnchan import create_test_channels
 
+def keypair():
+    priv = ECPrivkey.generate_random_key().get_secret_bytes()
+    k1 = Keypair(
+            pubkey=privkey_to_pubkey(priv),
+            privkey=priv)
+    return k1
+
+@contextmanager
+def noop_lock():
+    yield
+
 class MockNetwork:
     def __init__(self):
+        self.callbacks = defaultdict(list)
         self.lnwatcher = None
         user_config = {}
         user_dir = tempfile.mkdtemp(prefix="electrum-lnbase-test-")
@@ -18,49 +42,132 @@ class MockNetwork:
         self.asyncio_loop = asyncio.get_event_loop()
         self.channel_db = ChannelDB(self)
         self.interface = None
-    def register_callback(self, cb, trigger_names):
-        print("callback registered", repr(trigger_names))
-    def trigger_callback(self, trigger_name, obj):
-        print("callback triggered", repr(trigger_name))
+        self.path_finder = LNPathFinder(self.channel_db)
+
+    @property
+    def callback_lock(self):
+        return noop_lock()
+
+    register_callback = Network.register_callback
+    unregister_callback = Network.unregister_callback
+    trigger_callback = Network.trigger_callback
+
+    def get_local_height(self):
+        return 0
 
 class MockLNWorker:
-    def __init__(self, remote_peer_pubkey, chan):
+    def __init__(self, remote_keypair, local_keypair, chan):
         self.chan = chan
-        self.remote_peer_pubkey = remote_peer_pubkey
-        priv = ECPrivkey.generate_random_key().get_secret_bytes()
-        self.node_keypair = Keypair(
-                pubkey=privkey_to_pubkey(priv),
-                privkey=priv)
+        self.remote_keypair = remote_keypair
+        self.node_keypair = local_keypair
         self.network = MockNetwork()
+        self.channels = {self.chan.channel_id: self.chan}
+        self.invoices = {}
+
+    @property
+    def lock(self):
+        return noop_lock()
+
     @property
     def peers(self):
-        return {self.remote_peer_pubkey: self.peer}
+        return {self.remote_keypair.pubkey: self.peer}
+
     def channels_for_peer(self, pubkey):
-        return {self.chan.channel_id: self.chan}
+        return self.channels
+
+    def save_channel(self, chan):
+        pass
+
+    get_invoice = LNWorker.get_invoice
+    _create_route_from_invoice = LNWorker._create_route_from_invoice
 
 class MockTransport:
     def __init__(self):
         self.queue = asyncio.Queue()
+
     async def read_messages(self):
         while True:
             yield await self.queue.get()
 
-class BadFeaturesTransport(MockTransport):
+class NoFeaturesTransport(MockTransport):
+    """
+    This answers the init message with a init that doesn't signal any features.
+    Used for testing that we require DATA_LOSS_PROTECT.
+    """
     def send_bytes(self, data):
         decoded = decode_msg(data)
         print(decoded)
         if decoded[0] == 'init':
             self.queue.put_nowait(gen_msg('init', lflen=1, gflen=1, localfeatures=b"\x00", globalfeatures=b"\x00"))
 
+class PutIntoOthersQueueTransport(MockTransport):
+    def __init__(self):
+        super().__init__()
+        self.other_mock_transport = None
+
+    def send_bytes(self, data):
+        self.other_mock_transport.queue.put_nowait(data)
+
+def transport_pair():
+    t1 = PutIntoOthersQueueTransport()
+    t2 = PutIntoOthersQueueTransport()
+    t1.other_mock_transport = t2
+    t2.other_mock_transport = t1
+    return t1, t2
+
 class TestPeer(unittest.TestCase):
     def setUp(self):
         self.alice_channel, self.bob_channel = create_test_channels()
-    def test_bad_feature_flags(self):
-        # we should require DATA_LOSS_PROTECT
-        mock_lnworker = MockLNWorker(b"\x00" * 32, self.alice_channel)
-        mock_transport = BadFeaturesTransport()
-        p1 = Peer(mock_lnworker, LNPeerAddr("bogus", 1337, b"\x00" * 32), request_initial_sync=False, transport=mock_transport)
+
+    def test_require_data_loss_protect(self):
+        mock_lnworker = MockLNWorker(keypair(), keypair(), self.alice_channel)
+        mock_transport = NoFeaturesTransport()
+        p1 = Peer(mock_lnworker, LNPeerAddr("bogus", 1337, b"\x00" * 33), request_initial_sync=False, transport=mock_transport)
         mock_lnworker.peer = p1
         with self.assertRaises(LightningPeerConnectionClosed):
             asyncio.get_event_loop().run_until_complete(asyncio.wait_for(p1._main_loop(), 1))
 
+    def test_payment(self):
+        k1, k2 = keypair(), keypair()
+        t1, t2 = transport_pair()
+        w1 = MockLNWorker(k1, k2, self.alice_channel)
+        w2 = MockLNWorker(k2, k1, self.bob_channel)
+        p1 = Peer(w1, LNPeerAddr("bogus1", 1337, k1.pubkey),
+                request_initial_sync=False, transport=t1)
+        p2 = Peer(w2, LNPeerAddr("bogus2", 1337, k2.pubkey),
+                request_initial_sync=False, transport=t2)
+        w1.peer = p1
+        w2.peer = p2
+        # mark_open won't work if state is already OPEN.
+        # so set it to OPENING
+        self.alice_channel.set_state("OPENING")
+        self.bob_channel.set_state("OPENING")
+        # this populates the channel graph:
+        p1.mark_open(self.alice_channel)
+        p2.mark_open(self.bob_channel)
+        amount_btc = 100000/Decimal(COIN)
+        payment_preimage = os.urandom(32)
+        RHASH = sha256(payment_preimage)
+        addr = LnAddr(
+                    RHASH,
+                    amount_btc,
+                    tags=[('c', lnutil.MIN_FINAL_CLTV_EXPIRY_FOR_INVOICE),
+                          ('d', 'coffee')
+                         ])
+        pay_req = lnencode(addr, w2.node_keypair.privkey)
+        w2.invoices[bh2u(RHASH)] = (bh2u(payment_preimage), pay_req)
+        l = asyncio.get_event_loop()
+        async def pay():
+            fut = asyncio.Future()
+            def evt_set(event, _lnworker, msg):
+                fut.set_result(msg)
+            w2.network.register_callback(evt_set, ['ln_message'])
+
+            addr, peer, coro = LNWorker._pay(w1, pay_req)
+            await coro
+            print("HTLC ADDED")
+            self.assertEqual(await fut, 'Payment received')
+            gath.cancel()
+        gath = asyncio.gather(pay(), p1._main_loop(), p2._main_loop())
+        with self.assertRaises(asyncio.CancelledError):
+            l.run_until_complete(gath)