[GUI] Installer - Add Electrum node option

[jp1ac4]

This is for #1223.

For now, it's possible to edit the node's settings but not to change node type.

Remaining tasks:

• Revert Cargo.toml once Add Electrum backend #1222 is merged.
• Update wording as per [GUI] Add Electrum backend option to Installer & update Settings #1223 (comment).

[jp1ac4]

I made a further change to the behaviour while checking the connection. It's safer to prevent the user editing config values until the connection check completes to ensure the values don't change in the meanwhile, which could mean the connection status applies to the wrong values.

I think this was already an issue with the current installer but I guess connection checks are usually quicker with a local bitcoind and so it was less likely to cause problems.

[jp1ac4]

I updated the liana dependency commit.

[jp1ac4]

@nondiremanuel I made minor wording changes to the following page to mention Electrum:

Then on the next page, the user can choose the node type:

Perhaps I should remove "full" from the title of this page.

[nondiremanuel]

For the first page, I was proposing to take the opportunity to make the text simpler and more understandable (at least in my view):

• I already have a node
  Select this option if you already have a bitcoin node running locally or remotely. Liana will connect to it.
• I want Liana to automatically install a Bitcoin node on my device
  Liana will install a pruned (i.e. "compressed") node on your computer. You won't need to do anything except having some disk space available (~25GB required) and waiting for the initial synchronization with the network (it can take some days according to your internet connection speed).
  [the two parenthesis with the estimation space and time possibly should be shown only if the network chosen is mainnet]

If there is no consensus with this, we can also leave it as you did (i.e. adding the Electrum mentions) and discuss the general wording for another time.

The second page was exactly what I had in mind. Thanks!

[jp1ac4]

I've updated the wording as suggested with some minor changes:

• I felt "truncated" might be more accurate than "compressed", but probably pruned already conveys this so didn't include that part.
• I added "on mainnet" after ~25 GB. We don't currently have the network selection available in the view. It should be simple to add as a follow-up commit if required and only display the additional info for mainnet.
• I used "depending on" instead of "according to" as I think it's more common this way but either should be fine.

I removed "full" from the title:

[pythcoiner]

30 GB looks more correct to me (signet chain included but it's only 2.2GB):

~/.liana/bitcoind ❯ sudo du datadir -sh                                                                    
29G     datadir

[pythcoiner]

can we add 127.0.0.1:50001 as placeholder here?
even if it's not likely the electrum server is on localhost, it indicate the user it should specify the port, and indicate 50001 is the default port.

[pythcoiner]

i'm wondering about one thing here, did the address still only accept ip addresses?
i think the default config on umbrel is to give access via umbrel.local instead of an ip as (i guess) almost user do not configure a static ip for their node.
cf this comment

[pythcoiner]

i'm wondering about one thing here, did the address still only accept ip addresses? i think the default config on umbrel is to give access via umbrel.local instead of an ip as (i guess) almost user do not configure a static ip for their node. cf this comment

tested on linux adding 192.168.1.21 electrum.local to /etc/hosts:

[jp1ac4]

I've made the suggested changes.

I now need to rebase on master as there's a conflict.

[jp1ac4]

tested on linux adding 192.168.1.21 electrum.local to /etc/hosts:

Thanks for testing that. Yep, currently the Liana config file accepts any string, which is the same as the underlying Electrum client. Whether we allow any string or not might change as part of #1222.

[jp1ac4]

Rebased on master.

[jp1ac4]

Sorry, I made a further change to the Electrum address validation.

[pythcoiner]

testing w/ several remote servers:

seems ok w/ both ssl/tcp

[pythcoiner]

Here we should rename "Bitcoin Core" into "Electrum server":

[pythcoiner]

Here we should also remove the rescan feature if electrum, but we should keep the block height, i often use it for know if liana is sync w/ the backend:

[pythcoiner]

I'm actually trying electrum (on an other machine on my local network) on regtest w/ 550 coins:

for every sync (so every 30 seconds) electrs needs around 10 seconds to answer the gui request.

if i click on Receive menu during this 10 seconds i got not address util all the requests done:

i wonder about 2 things:

• do we make some call to te electrum server for generate address? or it's the iced "event loop" that became overloaded?

• why we still make so much requests to electrum server after we are sync?

[pythcoiner]

trying to connect a mainnet wallet on regtest electrum fail as expected:

maybe we can try to detect network by genesis hash at the previous step (check connection click) and display a more explicit message to the user?
(i don't think this should be tackle in this PR but rather in a follow up)

[jp1ac4]

Updated liana dependency commit hash.

[pythcoiner]

Maybe we can add (in a follow up) the name/type of the electrum server (by sending a server.banner request

[jp1ac4]

Updated liana dependency commit hash.
Changed DaemonControl to mutable following changes to start_rescan in #1222.
Allow to start rescan also for Electrum.

[jp1ac4]

Added a commit to enable changing from one node type to another in the settings.

Note that in its current form, it'll be possible for someone who's using managed bitcoind to switch to Electrum in the settings. In this case, the GUI will not try to start the managed bitcoind the next time they launch the GUI. I could also prevent such a user from switching node type (indeed, they cannot edit the bitcoind settings currently).

I also made a fix to a previous commit so that we take into account whether a rescan is in progress in order to determine whether the Electrum settings can be edited.

[pythcoiner]

ACK 819eb92