Some regtest tests depend on manual fee injection to simulate certain
mempool conditions (e.g. lnwatcher_waits_until_fees_go_down). This is
done by manually injecting fee estimates into the `Network` object using
the `test_inject_fee_etas` cli command. However it can still happen that
the Network automatically updates its fee estimates from the connected
electrum server in the time between injecting the fee and the actual
tested logic making decisions based on the fee. This causes the test to
fail sometimes.
By setting the `test_disable_automatic_fee_eta_update` true the Network
will stop automatically updating the fee estimates and the test will
behave as expected.
'prepayment', which corresponds to the trusted part of the
lightning payment.
We use 2*sm.mining_fee, where 'mining_fee' is the flat part of
the server fee. However, future protocol should probably allow
to set a value that does not depend on 'mining_fee'.
(note that LND uses a hardcoded amount).
- CURRENT_WALLET is set when a single wallet is loaded in memory, and it
remains set after Electrum stops running.
- If several wallets are loaded at the same time, CURRENT_WALLET is unset,
and RPCs must specify the wallet explicitly (using --wallet for the CLI)
- The fallback to 'default_wallet' essentially only applies when
creating a new wallet file
This allows plugins to document the commands they add.
The docstring is parsed as a regular expression:
arg:<type>:<name>:<description>\n
Types are defined in commands.arg_types.
Note that this commit removes support for single letter
shortcuts in command options.
If a command is not properly documented, a warning is issued
with print(), because no logger is available at this point.
The class TxBatcher handles the creation, broadcast and replacement
of replaceable transactions. Callers (LNWatcher, SwapManager) use
methods add_payment_output and add_sweep_info. Transactions
created by TxBatcher may combine sweeps and outgoing payments.
Transactions created by TxBatcher will have their fee bumped
automatically (this was only the case for sweeps before).
TxBatcher manages several TxBatches. TxBatches are created
dynamically when needed.
The GUI does not touch txbatcher transactions:
- wallet.get_candidates_for_batching excludes txbatcher
transactions
- RBF dialogs do not work with txbatcher transactions
wallet:
- instead of reading config variables, make_unsigned_transaction
takes new parameters: base_tx, send_change_to_lighting
tests:
- unit tests in test_txbatcher.py (replaces test_sswaps.py)
- force all regtests to use MPP, so that we sweep transactions
with several HTLCs. This forces the payment manager to aggregate
first-stage HTLC tx inputs. second-stage are not batched for now.
Ideally, given an on-chain backup, after the remote force-closes, we should be able to spend our anchor output,
to CPFP the remote commitment tx (assuming the channel used OPTION_ANCHORS).
To spend the anchor output, we need to be able to sign with the local funding_privkey.
Previously we derived the funding_key from the channel_seed (which comes from os.urandom).
Prior to anchors, there was no use case for signing with the funding_key given a channel backup.
Now with anchors, we should make its derivation deterministic somehow, in a way so that it can
be derived given just an on-chain backup.
- one way would be to put some more data into the existing OP_RETURN
- uses block space
- the OP_RETURNs can be disabled via "use_recoverable_channels"
- only the initiator can use OP_RETURNs (so what if channel is in incoming dir?)
- instead, new scheme for our funding_key:
- we derive the funding_privkey from the lnworker root secret (derived from our bip32 seed)
- for outgoing channels:
- lnworker_root_secret + remote_node_id + funding_tx_nlocktime
- for incoming channels:
- lnworker_root_secret + remote_node_id + remote_funding_pubkey
- a check is added to avoid reusing the same key between channels:
not letting to user open more than one channel with the same peer in a single block
- only the first 16 bytes of the remote_node_id are used, as the onchain backup OP_RETURNs only contain that
- as the funding_privkey cannot be derived from the channel_seed anymore, it is included in the
imported channel backups, which in turn need a new version defined
- a wallet db upgrade is used to update already stored imported cbs
- alternatively we could keep the imported cbs as-is, so no new version, no new funding_privkey field, as it is clearly somewhat redundant given on-chain backups can reconstruct it
- however adding the field seems easier
- otherwise the existing code would try to derive the funding_privkey from the channel_seed
- also note: atm there is no field in the imported backups to distinguish anchor channels vs static-remotekey channels
