Create an example Ledger custom signer

[notmandatory]

Describe the enhancement

Create an example of a BDK wallet custom signer using the Ledger ledger_bitcoin_client crate. This might make sense to split into a new optional module. See the bitcoin_client_rs repo.

Use case

Since Ledger now provides a rust based client library and on-device descriptor and miniscript support it would be useful for BDK users to have an example custom signer that implements SignerCommon and InputSigner traits and could be added to a Wallet with the wallet.add_signer() function.

Additional context

This issue was inspired by a conversation with @Rob1Ham.

[Rob1Ham]

Having BDK natively interact with the ledger rust library would be a huge win!

Tagging @bigspider on the ledger team as well as @edouardparis @darosior @kloaec from the revault team who have ledger currently working with their wallet Liana. They may have some opinions on the utility of this.

[darosior]

Hey. We don't use BDK at the moment but happy to provide guidance on anything. Maybe worth mentionning our `async-hwi`: https://github.com/wizardsardine/async-hwi, an abstracted pure Rust [0] interface to signing devices that support Miniscript. It's mainly a project of Edouard but we intend to improve it over time, and maybe upstream it somewhere at some point. [0] As in it doesn't have to bundle a whole Python interpreter by re-using Andrew Chow's HWI. ------- Original Message ------- Le lundi 16 janvier 2023 à 3:38 PM, Rob Hamilton ***@***.***> a écrit :

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Having BDK natively interact with the ledger rust library would be a huge win! Tagging ***@***.***(https://github.com/bigspider) on the ledger team as well as ***@***.***(https://github.com/edouardparis) ***@***.***(https://github.com/darosior) ***@***.***(https://github.com/kloaec) from the revault team who have ledger currently working with their wallet Liana. They may have some opinions on the utility of this. — Reply to this email directly, [view it on GitHub](#833 (comment)), or [unsubscribe](https://github.com/notifications/unsubscribe-auth/AFLK3F5NZFGRMM3O3K27YSDWSVMN5ANCNFSM6AAAAAATXSZHIU). You are receiving this because you were mentioned.Message ID: ***@***.***>

[notmandatory]

Closing in favor of bitcoindevkit/bdk_wallet#20.