// executeCooperativeClose executes the initial phase of a user-executed
// cooperative channel close. The channel state machine is transitioned to the
// closing phase, then our half of the closing witness is sent over to the
// remote peer.
func (p *peer) executeCooperativeClose(channel *lnwallet.LightningChannel) (*wire.ShaHash, error) {
// Shift the channel state machine into a 'closing' state. This
// generates a signature for the closing tx, as well as a txid of the
// closing tx itself, allowing us to watch the network to determine
// when the remote node broadcasts the fully signed closing
// transaction.
sig, txid, err := channel.InitCooperativeClose()
if err != nil {
return nil, err
}
chanPoint := channel.ChannelPoint()
peerLog.Infof("Executing cooperative closure of "+
"ChanPoint(%v) with peerID(%v), txid=%v", chanPoint, p.id, txid)
// With our signature for the close tx generated, send the signature to
// the remote peer instructing it to close this particular channel
// point.
// TODO(roasbeef): remove encoding redundancy
closeSig, err := btcec.ParseSignature(sig, btcec.S256())
if err != nil {
return nil, err
}
closeReq := lnwire.NewCloseRequest(chanPoint, closeSig)
p.queueMsg(closeReq, nil)
return txid, nil
}
