Export a watch wallet only (with descriptors and without private keys) for an air gap setup

[Tracachang]

Is your feature request related to a problem? Please describe.

For long time I've seen users looking for a way to do an air gap setup with Bitcoin Core, since there were no easy way people tend to go with other solutions such as armory, electrum which offers an easy and friendly way to do it.

Since Bitcoin Core v 22.0 and with the command listdescriptors it can be done easily:

OFFLINE PC - Create a wallet with descriptors=true, export descriptors with "listdescriptors".
ONLINE PC - Create a wallet without privatekeys, descriptors=true, and importdescriptors to have a functional watch only wallet for receiving funds and create unsigned transactions.

Describe the solution you'd like

Instead of creating two wallets, one offline and a watch only and manually have to export/import descriptors, the wallet containing the private keys could offer an option like "exportwatchonly" that would generate a "watch_wallet.dat" without private keys and all descriptors already imported. Making very easy and user friendly the process to create an air gap setup.

[pinheadmz]

I don't understand how an "exportwatchonly" command is any more efficient or straight forward than listdescriptors -> importdescriptors ?

[Tracachang]

I don't understand how an "exportwatchonly" command is any more efficient or straight forward than listdescriptors -> importdescriptors

I did not mean it would be more efficient but much more user friendly (as already exists in electrum for example) to have an option that creates a "watch_wallet.DAT" that they can just load instead of manually listdescriptors and import:

importdescriptors "[{\"desc\": \"wpkh([66bb13d5/84'/0'/0']xpub6CtDSW4S3XVd5uYp9CgsLTZKQcKieJSmjehcvfVJBSy1rPbkKNU3T6UmZ3mn7DoSsTsM6uH8ZKem7LQh3PHyrBAtZopSvF2tonEE7foTWFe/1/*)#a9twa6j5\", \"range\": [0, 1000], \"timestamp\": 1647182091, \"internal\": true, \"watchonly\": true, \"active\": true}]"

[pinheadmz]

I was able to do what you want to do with a few bash commands (see below).

I suppose we could add arguments -file <path/to/file> to both listdescriptors and importdescriptors that would make this even easier...?

$ bccli -regtest createwallet original
{
  "name": "original",
  "warning": ""
}

$ bccli -regtest listdescriptors | jq .descriptors -c >> ~/Desktop/watchonly.json
$ bccli -regtest -named createwallet wallet_name=watchonly disable_private_keys=true
{
  "name": "watchonly",
  "warning": ""
}

$ bccli -regtest -rpcwallet=watchonly importdescriptors $(cat ~/Desktop/watchonly.json)
[
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  }
]

[Tracachang]

I was able to do what you want to do with a few bash commands (see below).

I suppose we could add arguments -file <path/to/file> to both listdescriptors and importdescriptors that would make this even easier...?

Yes please, that would be great.

[Tracachang]

@pinheadmz

I have followed all the steps using the bash commands from your previous answer and using the watch_wallet from the GUI, I am unable to create a receiving taproot address ( it shows both base58 legacy & p2sh-segwit and bech32 but not bech32m).
If I select the "original_wallet" it appears in the GUI all 4 types of address including bech32m.

In any case, from console I can getnewaddress "test" "bech32m" and it works for watch_wallet but for some reason not on GUI.

[pinheadmz]

Hm, seems to work for me on master branch. The taproot addresses are identical from each wallet.

[Tracachang]

Hm, seems to work for me on master branch. The taproot addresses are identical from each wallet.

Did not try the master branch, I am on v.24.0.1

[pinheadmz]

Ok I just pulled v24.0.1 and repeated steps with CLI and GUI, same outcome -- are you still unable to do this?

[Tracachang]

Ok I just pulled v24.0.1 and repeated steps with CLI and GUI, same outcome -- are you still unable to do this?

Just tried again following this commands and I am still unable to see taproot in GUI

$ bitcoin-cli createwallet original
{
  "name": "original",
  "warning": ""
}

$ bitcoin-cli -rpcwallet=original listdescriptors | jq .descriptors -c >> ~/Desktop/watchonly.json
$ bitcoin-cli -named createwallet wallet_name=watchonly disable_private_keys=true
{
  "name": "watchonly_original",
  "warning": ""
}

$ bitcoin-cli -rpcwallet=watchonly importdescriptors $(cat ~/Desktop/watchonly.json)
[
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  },
  {
    "success": true
  }
]

[pinheadmz]

Just tried again following this commands and I am still unable to see taproot in GUI

at all? or just in the watch-only wallet?

[Tracachang]

Just tried again following this commands and I am still unable to see taproot in GUI

at all? or just in the watch-only wallet?

Just on GUI with the watch-only wallet, but on console using watch-only I can create taproot receiving addresses.

[pinheadmz]

@Tracachang We're going to close this issue as "won't fix" for now. I'm going to follow up in #9492 where I see you've already chimed in. I think a simple doc outlining the list/import descriptor commands I commented above and using PSBT for signing would be the most valuable.

As far as the missing taproot addresses in the GUI you've reported - that could be opened as a new issue if you can provide steps to reproduce it with the latest release of Bitcoin Core or master branch (I was unable to reproduce personally)