watchtower-plugin

[sr-gi]

List of pending improvements / simplifications:

• options::Value does not have an utility function to be casted to it's members (e.g. Value::to_i64) meaning that options need to be unwrapped and cast or set their corresponding default. This implies a lot of boilerplate:

  rust-teos/watchtower-plugin/src/main.rs

  Lines 602 to 608 in e19bb20

  	let max_elapsed_time =
  	if let Value::Integer(x) = plugin.option("watchtower-max-retry-time").unwrap() {
  	x as u16
  	} else {
  	// We will never end up here, but we need to define an else. Should be fixed alongside the previous fixme.
  	900
  	};

  .
• The client and the tower should agree on what is the current block height when an appointment is sent. Currently there is no easy way to do this given we need to use cln-rpc but we have no way of getting where the rpc file is placed. We could hardcode it but it would be pretty ugly. This can be fixed by reading the corresponding field in the Plugin::configuration vector, but such field is not in the currently released version of cln-plugin (https://github.com/ElementsProject/lightning/blob/d2633d3e6d56bf4594910cffad5b05fe583f72e5/plugins/src/lib.rs#L97).
• Using Tor in lightningd can be enabled using two options: proxy and always-use-proxy. The former sets what the proxy address is and the later whether to accept clearnet addresses or only "proxied" ones (.onion). We should be parsing these two options to decide whether Tor is enabled or not for the plugin too, however, this is also part of the aforementioned configuration vector, and currently we have no access to that. The current workaround is adding a plugin option: watchtower-proxy

[sr-gi]

• Simplifies the cln plugin option parsing #170 fixes option::Value
• Improves tor flag logic in watchtower-plugin #160 fixes proxy and always-use-proxy