electrum/lib/lnworker.py

import traceback
import sys
import json
import binascii
import asyncio
import time
import os
from decimal import Decimal
import binascii
import asyncio


from . import constants
from .bitcoin import sha256, COIN
from .util import bh2u, bfh, PrintError
from .constants import set_testnet, set_simnet
from .simple_config import SimpleConfig
from .network import Network
from .storage import WalletStorage
from .wallet import Wallet
from .lnbase import Peer, Outpoint, ChannelConfig, LocalState, RemoteState, Keypair, OnlyPubkeyKeypair, OpenChannel, ChannelConstraints, RevocationStore, aiosafe, calc_short_channel_id, privkey_to_pubkey
from .lightning_payencode.lnaddr import lnencode, LnAddr, lndecode
from . import lnrouter


is_key = lambda k: k.endswith("_basepoint") or k.endswith("_key")

def maybeDecode(k, v):
    if k in ["node_id", "short_channel_id", "pubkey", "privkey", "last_per_commitment_point", "next_per_commitment_point", "per_commitment_secret_seed"] and v is not None:
        return binascii.unhexlify(v)
    return v

def decodeAll(v):
    return {i: maybeDecode(i, j) for i, j in v.items()} if isinstance(v, dict) else v

def typeWrap(k, v, local):
    if is_key(k):
        if local:
            return Keypair(**v)
        else:
            return OnlyPubkeyKeypair(**v)
    return v

def reconstruct_namedtuples(openingchannel):
    openingchannel = decodeAll(openingchannel)
    openingchannel=OpenChannel(**openingchannel)
    openingchannel = openingchannel._replace(funding_outpoint=Outpoint(**openingchannel.funding_outpoint))
    new_local_config = {k: typeWrap(k, decodeAll(v), True) for k, v in openingchannel.local_config.items()}
    openingchannel = openingchannel._replace(local_config=ChannelConfig(**new_local_config))
    new_remote_config = {k: typeWrap(k, decodeAll(v), False) for k, v in openingchannel.remote_config.items()}
    openingchannel = openingchannel._replace(remote_config=ChannelConfig(**new_remote_config))
    new_local_state = decodeAll(openingchannel.local_state)
    openingchannel = openingchannel._replace(local_state=LocalState(**new_local_state))
    new_remote_state = decodeAll(openingchannel.remote_state)
    new_remote_state["revocation_store"] = RevocationStore.from_json_obj(new_remote_state["revocation_store"])
    openingchannel = openingchannel._replace(remote_state=RemoteState(**new_remote_state))
    openingchannel = openingchannel._replace(constraints=ChannelConstraints(**openingchannel.constraints))
    return openingchannel

def serialize_channels(channels):
    serialized_channels = []
    for chan in channels:
        namedtuples_to_dict = lambda v: {i: j._asdict() if isinstance(j, tuple) else j for i, j in v._asdict().items()}
        serialized_channels.append({k: namedtuples_to_dict(v) if isinstance(v, tuple) else v for k, v in chan._asdict().items()})
    class MyJsonEncoder(json.JSONEncoder):
        def default(self, o):
            if isinstance(o, bytes):
                return binascii.hexlify(o).decode("ascii")
            if isinstance(o, RevocationStore):
                return o.serialize()
            return super(MyJsonEncoder, self)
    dumped = MyJsonEncoder().encode(serialized_channels)
    roundtripped = json.loads(dumped)
    reconstructed = [reconstruct_namedtuples(x) for x in roundtripped]
    if reconstructed != channels:
        raise Exception("Channels did not roundtrip serialization without changes:\n" + repr(reconstructed) + "\n" + repr(channels))
    return roundtripped




# hardcoded nodes
node_list = [
    ('ecdsa.net', '9735', '038370f0e7a03eded3e1d41dc081084a87f0afa1c5b22090b4f3abb391eb15d8ff'),
]



class LNWorker(PrintError):

    def __init__(self, wallet, network):
        self.wallet = wallet
        self.network = network
        self.privkey = sha256(b"0123456789")
        self.config = network.config
        self.peers = {}
        # view of the network
        self.nodes = {}  # received node announcements
        self.channel_db = lnrouter.ChannelDB()
        self.path_finder = lnrouter.LNPathFinder(self.channel_db)
        self.channels = [reconstruct_namedtuples(x) for x in wallet.storage.get("channels", {})]
        peer_list = network.config.get('lightning_peers', node_list)
        self.channel_state = {chan.channel_id: "OPENING" for chan in self.channels}
        for host, port, pubkey in peer_list:
            self.add_peer(host, int(port), pubkey)
        # wait until we see confirmations
        self.network.register_callback(self.on_network_update, ['updated', 'verified']) # thread safe
        self.on_network_update('updated') # shortcut (don't block) if funding tx locked and verified

    def add_peer(self, host, port, pubkey):
        node_id = bfh(pubkey)
        channels = list(filter(lambda x: x.node_id == node_id, self.channels))
        peer = Peer(host, int(port), node_id, self.privkey, self.network, self.channel_db, self.path_finder, self.channel_state, channels, request_initial_sync=True)
        self.network.futures.append(asyncio.run_coroutine_threadsafe(peer.main_loop(), asyncio.get_event_loop()))
        self.peers[node_id] = peer

    def save_channel(self, openchannel):
        if openchannel.channel_id not in self.channel_state:
            self.channel_state[openchannel.channel_id] = "OPENING"
        self.channels = [openchannel] # TODO multiple channels
        dumped = serialize_channels(self.channels)
        self.wallet.storage.put("channels", dumped)
        self.wallet.storage.write()

    def save_short_chan_id(self, chan):
        """
        Checks if the Funding TX has been mined. If it has save the short channel ID to disk and return the new OpenChannel.

        If the Funding TX has not been mined, return None
        """
        assert self.channel_state[chan.channel_id] == "OPENING"
        peer = self.peers[chan.node_id]
        conf = self.wallet.get_tx_height(chan.funding_outpoint.txid)[1]
        if conf >= chan.constraints.funding_txn_minimum_depth:
            block_height, tx_pos = self.wallet.get_txpos(chan.funding_outpoint.txid)
            if tx_pos == -1:
                self.print_error('funding tx is not yet SPV verified.. but there are '
                                 'already enough confirmations (currently {})'.format(conf))
                return None
            chan = chan._replace(short_channel_id = calc_short_channel_id(block_height, tx_pos, chan.funding_outpoint.output_index))
            self.save_channel(chan)
            return chan
        return None

    def on_network_update(self, event, *args):
        for chan in self.channels:
            if self.channel_state[chan.channel_id] == "OPEN":
                continue
            chan = self.save_short_chan_id(chan)
            if not chan:
                self.print_error("network update but funding tx is still not at sufficient depth")
                continue
            peer = self.peers[chan.node_id]
            asyncio.run_coroutine_threadsafe(self.wait_funding_locked_and_mark_open(peer, chan), asyncio.get_event_loop())

    # aiosafe because we don't wait for result
    @aiosafe
    async def wait_funding_locked_and_mark_open(self, peer, chan):
        if self.channel_state[chan.channel_id] == "OPEN":
            return
        if not chan.local_state.funding_locked_received:
            chan = await peer.funding_locked(chan)
            self.save_channel(chan)
            self.print_error("CHANNEL OPENING COMPLETED")
        self.channel_state[chan.channel_id] = "OPEN"

    # not aiosafe because we call .result() which will propagate an exception
    async def _open_channel_coroutine(self, node_id, amount, push_msat, password):
        peer = self.peers[bfh(node_id)]
        openingchannel = await peer.channel_establishment_flow(self.wallet, self.config, password, amount, push_msat, temp_channel_id=os.urandom(32))
        self.print_error("SAVING OPENING CHANNEL")
        self.save_channel(openingchannel)

    def open_channel(self, node_id, local_amt, push_amt, pw):
        coro = self._open_channel_coroutine(node_id, local_amt, push_amt, None if pw == "" else pw)
        return asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop).result()
        #chan = fut.result()
        # https://api.lightning.community/#listchannels
        #std_chan = {"chan_id": chan.channel_id}
        #emit_function({"channels": [std_chan]})

    def get_paid(self):
        coro = self._get_paid_coroutine()
        return asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop).result()

    def pay(self, invoice):
        coro = self._pay_coroutine(invoice)
        return asyncio.run_coroutine_threadsafe(coro, self.network.asyncio_loop).result()

    def list_channels(self):
        return serialize_channels(self.channels)

    # not aiosafe because we call .result() which will propagate an exception
    async def _pay_coroutine(self, invoice):
        openchannel = self.channels[0]
        addr = lndecode(invoice, expected_hrp=constants.net.SEGWIT_HRP)
        payment_hash = addr.paymenthash
        pubkey = addr.pubkey.serialize()
        msat_amt = int(addr.amount * COIN * 1000)
        peer = self.peers[openchannel.node_id]
        openchannel = await peer.pay(self.wallet, openchannel, msat_amt, payment_hash, pubkey, addr.min_final_cltv_expiry)
        self.save_channel(openchannel)

    # not aiosafe because we call .result() which will propagate an exception
    async def _get_paid_coroutine(self):
        openchannel = self.channels[0]
        payment_preimage = os.urandom(32)
        RHASH = sha256(payment_preimage)
        expected_received_sat = 200000
        expected_received_msat = expected_received_sat * 1000
        peer = self.peers[openchannel.node_id]
        pay_req = lnencode(LnAddr(RHASH, amount=1/Decimal(COIN)*expected_received_sat, tags=[('d', 'one cup of coffee')]), peer.privkey)
        decoded = lndecode(pay_req, expected_hrp="sb")
        assert decoded.pubkey.serialize() == privkey_to_pubkey(self.privkey)
        print("payment request", pay_req)
        openchannel = await peer.receive_commitment_revoke_ack(openchannel, expected_received_msat, payment_preimage)
        self.save_channel(openchannel)

    def subscribe_payment_received_from_other_thread(self, emit_function):
        pass

    def subscribe_channel_list_updates_from_other_thread(self, emit_function):
        pass

    def subscribe_single_channel_update_from_other_thread(self, emit_function):
        pass

    def add_invoice_from_other_thread(self, amt):
        pass

    def subscribe_invoice_added_from_other_thread(self, emit_function):
        pass

    def pay_invoice_from_other_thread(self, lnaddr):
        pass