tlnrouter: add comments about path-finding blocking the asyncio loop - electrum - Electrum Bitcoin wallet
HTML git clone https://git.parazyd.org/electrum
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DIR Files
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---
DIR commit c95c0dcb8090e7e99a5706c3232077de7051db9b
DIR parent 05a191cc6a544adf625c70454540c8b79ea5ed7c
HTML Author: SomberNight <somber.night@protonmail.com>
Date: Mon, 9 Mar 2020 20:39:13 +0100
lnrouter: add comments about path-finding blocking the asyncio loop
Diffstat:
M electrum/lnrouter.py | 7 ++++++-
M electrum/lnworker.py | 7 +++++--
M electrum/tests/test_lnpeer.py | 6 +++---
3 files changed, 14 insertions(+), 6 deletions(-)
---
DIR diff --git a/electrum/lnrouter.py b/electrum/lnrouter.py
t@@ -146,7 +146,6 @@ class LNPathFinder(Logger):
return float('inf'), 0
if channel_policy.is_disabled():
return float('inf'), 0
- route_edge = RouteEdge.from_channel_policy(channel_policy, short_channel_id, end_node)
if payment_amt_msat < channel_policy.htlc_minimum_msat:
return float('inf'), 0 # payment amount too little
if channel_info.capacity_sat is not None and \
t@@ -155,6 +154,7 @@ class LNPathFinder(Logger):
if channel_policy.htlc_maximum_msat is not None and \
payment_amt_msat > channel_policy.htlc_maximum_msat:
return float('inf'), 0 # payment amount too large
+ route_edge = RouteEdge.from_channel_policy(channel_policy, short_channel_id, end_node)
if not route_edge.is_sane_to_use(payment_amt_msat):
return float('inf'), 0 # thanks but no thanks
t@@ -187,6 +187,11 @@ class LNPathFinder(Logger):
assert type(nodeB) is bytes
assert type(invoice_amount_msat) is int
if my_channels is None: my_channels = {}
+ # note: we don't lock self.channel_db, so while the path finding runs,
+ # the underlying graph could potentially change... (not good but maybe ~OK?)
+ # (but at the time of writing, we are called on the asyncio event loop,
+ # and the graph is also only updated from the event loop, so it will
+ # not change)
# FIXME paths cannot be longer than 20 edges (onion packet)...
DIR diff --git a/electrum/lnworker.py b/electrum/lnworker.py
t@@ -922,7 +922,10 @@ class LNWallet(LNWorker):
success = False
for i in range(attempts):
try:
- route = await self._create_route_from_invoice(decoded_invoice=lnaddr)
+ # note: this call does path-finding which takes ~1 second
+ # -> we will BLOCK the asyncio loop... (could just run in a thread and await,
+ # but then the graph could change while the path-finding runs on it)
+ route = self._create_route_from_invoice(decoded_invoice=lnaddr)
self.set_payment_status(payment_hash, PR_INFLIGHT)
self.network.trigger_callback('invoice_status', key)
payment_attempt_log = await self._pay_to_route(route, lnaddr)
t@@ -1035,7 +1038,7 @@ class LNWallet(LNWorker):
f"min_final_cltv_expiry: {addr.get_min_final_cltv_expiry()}"))
return addr
- async def _create_route_from_invoice(self, decoded_invoice) -> LNPaymentRoute:
+ def _create_route_from_invoice(self, decoded_invoice) -> LNPaymentRoute:
amount_msat = int(decoded_invoice.amount * COIN * 1000)
invoice_pubkey = decoded_invoice.pubkey.serialize()
# use 'r' field from invoice
DIR diff --git a/electrum/tests/test_lnpeer.py b/electrum/tests/test_lnpeer.py
t@@ -350,7 +350,7 @@ class TestPeer(ElectrumTestCase):
await asyncio.wait_for(p1.initialized, 1)
await asyncio.wait_for(p2.initialized, 1)
# alice sends htlc
- route = await w1._create_route_from_invoice(decoded_invoice=lnaddr)
+ route = w1._create_route_from_invoice(decoded_invoice=lnaddr)
htlc = p1.pay(route, alice_channel, int(lnaddr.amount * COIN * 1000), lnaddr.paymenthash, lnaddr.get_min_final_cltv_expiry())
# alice closes
await p1.close_channel(alice_channel.channel_id)
t@@ -370,14 +370,14 @@ class TestPeer(ElectrumTestCase):
pay_req = self.prepare_invoice(w2)
addr = w1._check_invoice(pay_req)
- route = run(w1._create_route_from_invoice(decoded_invoice=addr))
+ route = w1._create_route_from_invoice(decoded_invoice=addr)
run(w1.force_close_channel(alice_channel.channel_id))
# check if a tx (commitment transaction) was broadcasted:
assert q1.qsize() == 1
with self.assertRaises(NoPathFound) as e:
- run(w1._create_route_from_invoice(decoded_invoice=addr))
+ w1._create_route_from_invoice(decoded_invoice=addr)
peer = w1.peers[route[0].node_id]
# AssertionError is ok since we shouldn't use old routes, and the