The Setup

You need to use Bitcoinlib version 0.7 or higher for this setup to work, older versions do not support connections to multiple bitcoind wallets.

You need Bitcoin Core version 0.21 or higher. In version 0.21 descriptor wallets where introduced. Descriptor wallets can easily export public master account keys, so you can generate new keys / addresses in Bitcoinlib.

• Bitcoinlib >= 0.7
• Bitcoin node >= 0.21

Create wallets in Bitcoin Core

First create two Bitcoin wallets on the device with a running and fully synced Bitcoin Core node:

$ bitcoin-cli createwallet bclwallet1
$ bitcoin-cli createwallet bclwallet2

The Bitcoin nodes now has two wallets, you can export descriptors with the listdescriptors command. This command export a list of public master account keys in the descriptor format. Notice in the command below you have to add the '-rpcwallet=bclwallet1' option so the node knows which wallet you use.

bitcoin-cli -rpcwallet=bclwallet1 listdescriptors

In the list of descriptors you can find the wallet's public master account key for segregated witness keys, you can recognise the key path looks like: [.../84h/1h/0h]. Where 84h is the code for segwit key paths.

wpkh([9af741ff/84h/1h/0h]tpubDDLXsfWUnPRrYLceKtRq38L6KhXFgN6zuJ46RDn5KgPs57QbMV8HRB9TTUNj1vVZXD4KaDnf5r1fBa2GeNwBzP1i6aPwLn1YfiZgCcvaPGW/0/*)#jf9hpecn

The tpub... is the public key you need to copy to Bitcoinlib to create and manage the wallet there. Repeat the steps above for the second wallet.

Before we connect the wallet we need to correctly setup the connection to Bitcoind. To do this add the correct connection string in the .bitcoinlib/providers.json file.

"bitcoind.testnet": {
    "provider": "bitcoind",
    "network": "testnet",
    "client_class": "BitcoindClient",
    "provider_coin_id": "",
    "url": "http://local:...mypassword...@bitcoinnode:18332/wallet/{wallet_name}",
    "api_key": "",
    "priority": 10,
    "denominator": 100000000,
    "network_overrides": null
},

Fill in your own username, password and servername. Leave the '{wallet_name}' string intact, this will be replaced in Bitcoinlib's bitcoind service client.

To test the connection you can perform a simple blockcount request.

srv = Service(network='testnet', providers=['bitcoind'])
print(srv.blockcount())

The last step is to create the wallets in Bitcoinlib. To do so copy the public master key into your Python code. Also be sure to use the same wallet name in Python as in Bitcoin Core. If your provider.json file contains more then the link to your Bitcoin node you need to specify the use of bitcoind, or else it will result in a lot of incorrect requests to other service providers.

This code show how to connect the first wallet, the code is the same for the second wallet (with the correct key and wallet name of course). You can add and connect as many wallets as you like.

pubmaster1 = \
    'tpubDDLXsfWUnPRrYLceKtRq38L6KhXFgN6zuJ46RDn5KgPs57QbMV8HRB9TTUNj1vVZXD4KaDnf5r1fBa2GeNwBzP1i6aPwLn1YfiZgCcvaPGW'
w = wallet_create_or_open('bclwallet1', witness_type='segwit', keys=pubmaster1)
w.providers = ['bitcoind']
w.scan(scan_gap_limit=1)
w.info()

That is all there is to it. You can now easily update your wallet, create new keys and send / receive funds.