When gossip is enabled we waste a lot of time trying to connect
to onion peers if we don't have a proxy enabled. We should just skip
them and try to connect to clearnet peers instead.
```
$ export ELECTRUM_LINTERS=E9,E101,E129,E273,E274,E703,E71,E722,F5,F6,F7,F8,W191,W29,B
$ export ELECTRUM_LINTERS_IGNORE=B007,B009,B010,B019,B036,F541,F841
$ flake8 . --count --select="$ELECTRUM_LINTERS" --ignore="$ELECTRUM_LINTERS_IGNORE" --show-source --statistics --exclude "*_pb2.py,electrum/_vendor/"
./electrum/commands.py:98:1: F811 redefinition of unused 'format_satoshis' from line 48
def format_satoshis(x):
^
./electrum/commands.py:437:9: F811 redefinition of unused 'Mnemonic' from line 62
from .mnemonic import Mnemonic
^
./electrum/gui/qt/wizard/wallet.py:37:5: F811 redefinition of unused 'Daemon' from line 14
from electrum.daemon import Daemon
^
./electrum/lntransport.py:14:1: F811 redefinition of unused 'Optional' from line 12
from typing import NamedTuple, List, Tuple, Mapping, Optional, TYPE_CHECKING, Union, Dict, Set, Sequence
^
./electrum/lntransport.py:14:1: F811 redefinition of unused 'TYPE_CHECKING' from line 12
from typing import NamedTuple, List, Tuple, Mapping, Optional, TYPE_CHECKING, Union, Dict, Set, Sequence
^
./electrum/plugin.py:966:13: F811 redefinition of unused 'hid' from line 593
import hid
^
./electrum/plugin.py:1040:13: F811 redefinition of unused 'hid' from line 593
import hid
^
./electrum/util.py:44:1: F811 redefinition of unused 'json' from line 26
import json
^
./electrum/util.py:46:1: F811 redefinition of unused 'NamedTuple' from line 29
from typing import NamedTuple, Optional
^
./electrum/util.py:46:1: F811 redefinition of unused 'Optional' from line 29
from typing import NamedTuple, Optional
^
./electrum/util.py:1456:56: F811 redefinition of unused 'traceback' from line 34
async def __aexit__(self, exc_type, exc_value, traceback):
^
./electrum/wallet_db.py:536:9: F811 redefinition of unused 'LOCAL' from line 46
LOCAL = 1
^
./electrum/wallet_db.py:537:9: F811 redefinition of unused 'REMOTE' from line 46
REMOTE = -1
^
./tests/test_bitcoin.py:28:1: F811 redefinition of unused 'bitcoin' from line 9
from electrum import crypto, constants, bitcoin
^
./tests/test_txbatcher.py:11:1: F811 redefinition of unused 'Transaction' from line 7
from electrum.transaction import Transaction, PartialTxInput, PartialTxOutput, TxOutpoint
^
./tests/test_wallet_vertical.py:20:1: F811 redefinition of unused 'Transaction' from line 10
from electrum.transaction import Transaction, PartialTxOutput, tx_from_any, Sighash
^
16 F811 redefinition of unused 'format_satoshis' from line 48
16
```
This will be useful if we decide to ship lntransport as a separate
package. It is also a conceptual cleanup.
Notes:
- lntransport still requires crypto.py
- parsing node id from a bolt11 invoice is not supported.
In particular, in the regtests, with incoming peers, we can have multiple transports open with the same node simultaneously
(see e.g. lnworker._request_force_close_from_backup).
We now use the first few bytes of peer_pubkey, as that is potentially familiar to users,
and the first few bytes of sha256(id(self)) to mitigate collisions in case the peer_pubkeys collide.
log excerpt:
```
I/P | lnpeer.Peer.[LNWallet, 030f0bf260-e0b33756] | handshake done for 030f0bf260acdbd3edcad84d7588ec7c5df4711e87e6a23016f989b8d3a4147230@163.172.94.64:9735
D/P | lnpeer.Peer.[LNWallet, 030f0bf260-e0b33756] | Sending INIT
I/P | lnpeer.Peer.[LNWallet, 03933884aa-5e5dce45] | handshake done for 03933884aaf1d6b108397e5efe5c86bcf2d8ca8d2f700eda99db9214fc2712b134@34.250.234.192:9735
D/P | lnpeer.Peer.[LNWallet, 03933884aa-5e5dce45] | Sending INIT
D/P | lnpeer.Peer.[LNWallet, 030f0bf260-e0b33756] | Received INIT
I/P | lnpeer.Peer.[LNWallet, 02651acf4a-79696c42] | handshake done for 02651acf4a7096091bf42baad19b3643ea318d6979f6dcc16ebaec43d5b0f4baf2@82.119.233.36:19735
D/P | lnpeer.Peer.[LNWallet, 02651acf4a-79696c42] | Sending INIT
D/P | lnpeer.Peer.[LNWallet, 03933884aa-5e5dce45] | Received INIT
I/P | lnpeer.Peer.[LNWallet, 030f0bf260-e0b33756] | saved remote_update
D/P | lnpeer.Peer.[LNWallet, 030f0bf260-e0b33756] | Received CHANNEL_REESTABLISH
```
Previously for incoming transports, the diagnostic_name (for log messages)
was just "responder" -- not sufficient to distinguish peers.
We now use the pubkey instead.
For outgoing transports it is f"{host}:{port}" (unchanged).
We could just use the pubkey for both uniformly; but it is quite long, and
it is hard to distinguish them at a glance.
Scenario (prior this change):
A task in lnpeer.Peer.taskgroup raises ORIG_EXC, e.g. in htlc_switch.
The taskgroup then cancels all its tasks and then awaits each (in cancel_remaining):
https://github.com/kyuupichan/aiorpcX/blob/4e64c560422b1fc1dcebc2f926f4b74894e34cdf/aiorpcx/curio.py#L217-L221
In Peer.main_loop, we would want ORIG_EXC to be raised,
but instead LightningPeerConnectionClosed() will be raised as
the Peer._message_loop() task is cancelled, and it is awaited first in cancel_remaining.
We should make sure that if a task is cancelled it will let the CancelledError
propagate out, or at least it does not raise a different exception instead.
In recv_rev() previously all unacked_local_updates were deleted
as it was assumed that all of them have been acked at that point by
the revoke_and_ack itself. However this is not necessarily the case:
see new test case.
renamed log['unacked_local_updates'] to log['unacked_local_updates2']
to avoid breaking existing wallet files
pycryptodomex 3.7 implemented chacha20_poly1305 and chacha20,
and it is already used (although optionally) to speed up AES,
so we can remove cryptography and make pycryptodomex mandatory for LN
f321x