Merge #200: feat: add non-persisted Async Payjoin support

c6bce58 docs: add Payjoin capability to the README (Mehmet Efe Umit)
4cab2fa feat: add payjoin receive support (Mehmet Efe Umit)
0112c92 feat: add payjoin send support (Mehmet Efe Umit)
f62287a refactor: move broadcast to a helper function (Mehmet Efe Umit)
a28076a refactor: move sync to a helper function (Mehmet Efe Umit)

Pull request description:

  ### Description

  This change implements the online commands for both sending and receiving a Payjoin. Note that this PR does not implement Payjoin persistence.

  ### Notes to the reviewers

  Tested on my local regtest with rpc  using the OHTTP relays and directories in the [payjoin-cli README](https://github.com/payjoin/rust-payjoin/tree/master/payjoin-cli). Feel free to do the same, and let me know if there are comments, documentation, etc. which should be changed with this. I was not able to find any...

  Here are the sample command you can use to test on regtest:

  **Send**
  ```
  cargo run --features=rpc -- -n regtest wallet -a USERNAME:PASSWORD -w WALLET_NAME -e "DESCRIPTOR" send_payjoin --ohttp_relay "RELAY1" --ohttp_relay "RELAY2" --fee_rate 1 --uri "URI"
  ```
  **Receive**
  ```
  cargo run --features=rpc -- -n regtest wallet -a USERNAME:PASSWORD -w WALLET_NAME -e "DESCRIPTOR" receive_payjoin --max_fee_rate 1000 --directory "https://payjo.in"  --ohttp_relay "RELAY1" --ohttp_relay "RELAY2" --amount AMOUNT
  ```
  ### Checklists

  #### All Submissions:

  * [x] I've signed all my commits
  * [X] I followed the [contribution guidelines](https://github.com/bitcoindevkit/bdk-cli/blob/master/CONTRIBUTING.md)
  * [X] I ran `cargo fmt` and `cargo clippy` before committing

  #### New Features:

  * [] I've added tests for the new feature  <--- There is no testing suite for this.
  * [X] I've added docs for the new feature
  * [N/A] I've updated `CHANGELOG.md`

  #### Bugfixes:

  * [ ] This pull request breaks the existing API
  * [ ] I've added tests to reproduce the issue which are now passing
  * [ ] I'm linking the issue being fixed by this PR

ACKs for top commit:
  tvpeter:
    tACK c6bce58
  spacebear21:
    utACK c6bce58

Tree-SHA512: 1da8295d0eedf6fd31095085e6ef0d90ab46d5eed6c2f21a7539a6c3ff6d1127d0cdbb664d519bcb4a783ea2707452bf8cd3cb961a67ba3e61d989701e205dca

Author: tvpeter

Cargo.lock

@@ -21,6 +21,8 @@ serde_json = "1.0"
 thiserror = "2.0.11"
 tokio = { version = "1", features = ["full"] }
 cli-table = "0.5.0"
+tracing = "0.1.41"
+tracing-subscriber = "0.3.20"
 
 # Optional dependencies
 bdk_bitcoind_rpc = { version = "0.21.0", features = ["std"], optional = true }
@@ -29,8 +31,9 @@ bdk_esplora = { version = "0.22.1", features = ["async-https", "tokio"], optiona
 bdk_kyoto = { version = "0.15.1", optional = true }
 bdk_redb = { version = "0.1.0", optional = true }
 shlex = {  version = "1.3.0", optional = true }
-tracing = "0.1.41"
-tracing-subscriber = "0.3.20"
+payjoin = { version = "1.0.0-rc.1", features = ["v1", "v2", "io", "_test-utils"], optional = true}
+reqwest = { version = "0.12.23", default-features = false, optional = true }
+url = { version = "2.5.4", optional = true }
 
 [features]
 default = ["repl", "sqlite"]
@@ -43,10 +46,13 @@ sqlite = ["bdk_wallet/rusqlite"]
 redb = ["bdk_redb"]
 
 # Available blockchain client options
-cbf = ["bdk_kyoto"]
-electrum = ["bdk_electrum"]
-esplora = ["bdk_esplora"]
-rpc = ["bdk_bitcoind_rpc"]
+cbf = ["bdk_kyoto", "_payjoin-dependencies"]
+electrum = ["bdk_electrum", "_payjoin-dependencies"]
+esplora = ["bdk_esplora", "_payjoin-dependencies"]
+rpc = ["bdk_bitcoind_rpc", "_payjoin-dependencies"] 
+
+# Internal features
+_payjoin-dependencies = ["payjoin", "reqwest", "url"]
 
 # Use this to consensus verify transactions at sync time
 verify = []

Cargo.toml

@@ -35,6 +35,7 @@ And yes, it can do Taproot!!
 This crate can be used for the following purposes:
  - Instantly create a miniscript based wallet and connect to your backend of choice (Electrum, Esplora, Core RPC, Kyoto etc) and quickly play around with your own complex bitcoin scripting workflow. With one or many wallets, connected with one or many backends.
  - The `tests/integration.rs` module is used to document high level complex workflows between BDK and different Bitcoin infrastructure systems, like Core, Electrum and Lightning(soon TM).
+ - Receive and send Async Payjoins. Note that even though Async Payjoin as a protocol allows the receiver and sender to go offline during the payjoin, the BDK CLI implementation currently does not support persisting.
  - (Planned) Expose the basic command handler via `wasm` to integrate `bdk-cli` functionality natively into the web platform. See also the [playground](https://bitcoindevkit.org/bdk-cli/playground/) page.
 
 If you are considering using BDK in your own wallet project bdk-cli is a nice playground to get started with. It allows easy testnet and regtest wallet operations, to try out what's possible with descriptors, miniscript, and BDK APIs. For more information on BDK refer to the [website](https://bitcoindevkit.org/) and the [rust docs](https://docs.rs/bdk_wallet/1.0.0/bdk_wallet/index.html)
@@ -112,6 +113,18 @@ To generate a new extended master key, suitable for use in a descriptor:
 cargo run -- key generate
 ```
 
+To start a Payjoin session as the receiver with regtest RPC and example OHTTP relays:
+
+```
+cargo run --features rpc -- wallet --wallet sample_wallet --url="127.0.0.1:18443" --ext-descriptor "wpkh(tprv8ZgxMBicQKsPd2PoUEcGNDHPZmVWgtPYERAwMG6qHheX6LN4oaazp3qZU7mykiaAZga1ZB2SJJR6Mriyq8MocMs7QTe7toaabSwTWu5fRFz/84h/1h/0h/0/*)#8guqp7rn" receive_payjoin --amount 21120000 --max_fee_rate 1000 --directory "https://payjo.in" --ohttp_relay "https://pj.bobspacebkk.com" --ohttp_relay "https://pj.benalleng.com"
+```
+
+To send a Payjoin with regtest RPC and example OHTTP relays:
+
+```
+cargo run --features rpc -- wallet --wallet sample_wallet --url="127.0.0.1:18443" --ext-descriptor "wpkh(tprv8ZgxMBicQKsPd2PoUEcGNDHPZmVWgtPYERAwMG6qHheX6LN4oaazp3qZU7mykiaAZga1ZB2SJJR6Mriyq8MocMs7QTe7toaabSwTWu5fRFz/84h/1h/0h/0/*)#8guqp7rn" send_payjoin --ohttp_relay "https://pj.bobspacebkk.com" --ohttp_relay "https://pj.benalleng.com" --fee_rate 1 --uri "<URI>"
+```
+
 ## Justfile
 
 We have added the `just` command runner to help you with common commands (during development) and running regtest `bitcoind` if you are using the `rpc` feature. 

README.md

@@ -430,6 +430,41 @@ pub enum OnlineWalletSubCommand {
         )]
         tx: Option<String>,
     },
+    // Generates a Payjoin receive URI and processes the sender's Payjoin proposal.
+    ReceivePayjoin {
+        /// Amount to be received in sats.
+        #[arg(env = "PAYJOIN_AMOUNT", long = "amount", required = true)]
+        amount: u64,
+        /// Payjoin directory which will be used to store the PSBTs which are pending action
+        /// from one of the parties.
+        #[arg(env = "PAYJOIN_DIRECTORY", long = "directory", required = true)]
+        directory: String,
+        /// URL of the Payjoin OHTTP relay. Can be repeated multiple times to attempt the
+        /// operation with multiple relays for redundancy.
+        #[arg(env = "PAYJOIN_OHTTP_RELAY", long = "ohttp_relay", required = true)]
+        ohttp_relay: Vec<String>,
+        /// Maximum effective fee rate the receiver is willing to pay for their own input/output contributions.
+        #[arg(env = "PAYJOIN_RECEIVER_MAX_FEE_RATE", long = "max_fee_rate")]
+        max_fee_rate: Option<u64>,
+    },
+    /// Sends an original PSBT to a BIP 21 URI and broadcasts the returned Payjoin PSBT.
+    SendPayjoin {
+        /// BIP 21 URI for the Payjoin.
+        #[arg(env = "PAYJOIN_URI", long = "uri", required = true)]
+        uri: String,
+        /// URL of the Payjoin OHTTP relay. Can be repeated multiple times to attempt the
+        /// operation with multiple relays for redundancy.
+        #[arg(env = "PAYJOIN_OHTTP_RELAY", long = "ohttp_relay", required = true)]
+        ohttp_relay: Vec<String>,
+        /// Fee rate to use in sat/vbyte.
+        #[arg(
+            env = "PAYJOIN_SENDER_FEE_RATE",
+            short = 'f',
+            long = "fee_rate",
+            required = true
+        )]
+        fee_rate: u64,
+    },
 }
 
 /// Subcommands for Key operations.

src/commands.rs

@@ -103,6 +103,15 @@ pub enum BDKCliError {
     #[cfg(feature = "cbf")]
     #[error("BDK-Kyoto update error: {0}")]
     KyotoUpdateError(#[from] bdk_kyoto::UpdateError),
+
+    #[cfg(any(
+        feature = "electrum",
+        feature = "esplora",
+        feature = "rpc",
+        feature = "cbf",
+    ))]
+    #[error("Reqwest error: {0}")]
+    ReqwestError(#[from] reqwest::Error),
 }
 
 impl From<ExtractTxError> for BDKCliError {