Fund channels

[Jasonvdb]

Right now this lib only allows for receiving channels from the other party (LSP). We should allow channels to be funded locally with a PSBT.

[tanx]

Right now this lib only allows for receiving channels from the other party (LSP). We should allow channels to be funded locally with a PSBT.

@Jasonvdb yes, I just came across this issue when I saw there seems to be no openChannel api. Is there example code that shows how to configure the library for LSP and is there an LSP instance available for testing? Thank you

[Jasonvdb]

I would say the easiest way to get up and running is spin up a local polar network and then run electrumx wired up to that bitcoin node in your network. It'll be much easier for development to have control of the mining.

Once that's setup update constants in the example app with your electrum server details and the LND node connection details that you can find in the polar UI here:

Then just use the polar terminal for your LND node to open up a channel with your LDK node in your simulator. Get the nodeID of your app tapping "Get info" in the example app. That copies the node ID to the clipboard.

lncli openchannel --node_key=028a088a9730a1e4358e4ff044784eaab1db334a93806b05ff2d4b84967b339cf8 --local_amt=100000 --push_amt=50000 --private=true

Mine a block or 2 with the "Quick Mine" button in Polar and you should be good to go.

We'll look at maybe setting up a open regtest network for this and then make it work out the box with the LSP. But for to get up and running now the above should be good. Ping me or Corey if you have any specific issues with the setup!

[tanx]

@Jasonvdb thanks! Polar is awesome... no idea why I haven't tried it until now. I can't seem to connect to the polar bitcoind rpc port from electrumx though. Opening http://127.0.0.1:18443 in my browser works. So the port is exposed to my host. I'm running the following cmd:

docker run -v /Users/user/electrumx:/data -e DAEMON_URL=http://polaruser:polarpass@127.0.0.1:18443 -e COIN=BitcoinSegwit -p 50001:50001 lukechilds/electrumx

I saw someone else had this issue. I'm not a docker expert myself. Any ideas?

[Jasonvdb]

Great yeah polar is super useful!

Are you getting the same error as in that issue? Or I see your command is missing -e NET=regtest so hopefully that's it?

[tanx]

Nope...

docker run -v /Users/tanx/electrumx:/data -e DAEMON_URL=http://polaruser:polarpass@127.0.0.1:18443 -e COIN=BitcoinSegwit -e NET=regtest -p 50001:50001 lukechilds/electrumx
INFO:electrumx:ElectrumX server starting
INFO:electrumx:logging level: INFO
INFO:Controller:Python version: 3.7.9 (default, Dec 17 2020, 08:26:10)  [GCC 9.3.0]
INFO:Controller:software version: ElectrumX 1.16.0
INFO:Controller:aiorpcX version: 0.18.7
INFO:Controller:supported protocol versions: 1.4-1.4.2
INFO:Controller:event loop policy: <uvloop.EventLoopPolicy object at 0xffff9af90910>
INFO:Controller:reorg limit is 8,000 blocks
INFO:Daemon:daemon #1 at 127.0.0.1:18443/ (current)
INFO:DB:switching current directory to /data
INFO:DB:using leveldb for DB backend
ERROR:Daemon:connection problem - check your daemon is running.  Retrying occasionally...

Maybe I need to allow the docker container access to the bitcoind rpc port?

[Jasonvdb]

Ok I managed to replicate, not sure why but it starts working when I replace 127.0.0.1 with my actual network IP 🤷

Quick command I use to get the right IP ifconfig | grep "netmask" or just from network settings.

[tanx]

@Jasonvdb genius! Thanks that did it. Wierd that it doesn't see localhost. Anyhow it works now. LDK client is now connected to electrum :) 🙏