From 238310e5149e11dad8dd19f123dcf6c13b08dc67 Mon Sep 17 00:00:00 2001
From: DanGould <d@ngould.dev>
Date: Fri, 6 Dec 2024 17:26:06 -0500
Subject: [PATCH 1/2] Expose de/serialize for Sender, Receiver

These structs need to be serialized and deserialized in order to be
persisted in a downstream database.

We use json to do this only because that decision was made in payjoin-cli.
A binary encoding could be used as well, but that bikeshed is to be built
at a later date.
---
 Cargo.lock         |  1 +
 Cargo.toml         |  1 +
 src/error.rs       |  4 ++++
 src/receive/mod.rs | 10 ++++++++++
 src/receive/uni.rs |  9 +++++++++
 src/send/mod.rs    | 10 ++++++++++
 src/send/uni.rs    |  9 +++++++++
 7 files changed, 44 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index cad9079..96f89b2 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2058,6 +2058,7 @@ dependencies = [
  "rcgen",
  "reqwest",
  "rustls 0.22.4",
+ "serde_json",
  "testcontainers",
  "testcontainers-modules",
  "thiserror 1.0.69",
diff --git a/Cargo.toml b/Cargo.toml
index eda73c7..e811c98 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -26,6 +26,7 @@ bitcoin-ffi = { git = "https://github.com/bitcoindevkit/bitcoin-ffi.git", rev =
 hex = "0.4.3"
 ohttp = { package = "bitcoin-ohttp", version = "0.6.0" }
 payjoin = { version = "0.21.0", features = ["send", "receive", "base64", "v2", "io"] }
+serde_json = "1.0.128"
 thiserror = "1.0.58"
 uniffi = { version = "0.28.0", optional = true }
 url = "2.5.0"
diff --git a/src/error.rs b/src/error.rs
index 7ca392e..da4763b 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -74,6 +74,9 @@ pub enum PayjoinError {
 
     #[error("{message}")]
     InputPairError { message: String },
+
+    #[error("{message}")]
+    SerdeJsonError { message: String },
 }
 
 macro_rules! impl_from_error {
@@ -99,6 +102,7 @@ impl_from_error! {
     OutputSubstitutionError => OutputSubstitutionError,
     InputContributionError => InputContributionError,
     PsbtInputError => InputPairError,
+    serde_json::Error => SerdeJsonError,
 }
 
 #[cfg(feature = "uniffi")]
diff --git a/src/receive/mod.rs b/src/receive/mod.rs
index 985ba6a..cb9dd39 100644
--- a/src/receive/mod.rs
+++ b/src/receive/mod.rs
@@ -97,6 +97,16 @@ impl Receiver {
     pub fn id(&self) -> String {
         <Self as Into<payjoin::receive::v2::Receiver>>::into(self.clone()).id().to_string()
     }
+
+    pub fn to_json(&self) -> Result<String, PayjoinError> {
+        serde_json::to_string(&self.0).map_err(|e| e.into())
+    }
+
+    pub fn from_json(json: &str) -> Result<Self, PayjoinError> {
+        let receiver = serde_json::from_str::<payjoin::receive::v2::Receiver>(json)
+            .map_err(<serde_json::Error as Into<PayjoinError>>::into)?;
+        Ok(receiver.into())
+    }
 }
 
 #[derive(Clone)]
diff --git a/src/receive/uni.rs b/src/receive/uni.rs
index a0cd5c8..71985b0 100644
--- a/src/receive/uni.rs
+++ b/src/receive/uni.rs
@@ -87,6 +87,15 @@ impl Receiver {
     pub fn id(&self) -> String {
         self.0.id()
     }
+
+    pub fn to_json(&self) -> Result<String, PayjoinError> {
+        self.0.to_json()
+    }
+
+    #[uniffi::constructor]
+    pub fn from_json(json: &str) -> Result<Self, PayjoinError> {
+        super::Receiver::from_json(json).map(Into::into)
+    }
 }
 
 #[cfg_attr(feature = "uniffi", derive(uniffi::Record))]
diff --git a/src/send/mod.rs b/src/send/mod.rs
index cba5cec..46ba803 100644
--- a/src/send/mod.rs
+++ b/src/send/mod.rs
@@ -124,6 +124,16 @@ impl Sender {
             Err(e) => Err(e.into()),
         }
     }
+
+    pub fn to_json(&self) -> Result<String, PayjoinError> {
+        serde_json::to_string(&self.0).map_err(|e| e.into())
+    }
+
+    pub fn from_json(json: &str) -> Result<Self, PayjoinError> {
+        let sender = serde_json::from_str::<payjoin::send::Sender>(json)
+            .map_err(<serde_json::Error as Into<PayjoinError>>::into)?;
+        Ok(sender.into())
+    }
 }
 
 /// Data required for validation of response.
diff --git a/src/send/uni.rs b/src/send/uni.rs
index 3d4828b..5595d84 100644
--- a/src/send/uni.rs
+++ b/src/send/uni.rs
@@ -125,6 +125,15 @@ impl Sender {
             Err(e) => Err(e),
         }
     }
+
+    pub fn to_json(&self) -> Result<String, PayjoinError> {
+        self.0.to_json()
+    }
+
+    #[uniffi::constructor]
+    pub fn from_json(json: &str) -> Result<Self, PayjoinError> {
+        super::Sender::from_json(json).map(Into::into)
+    }
 }
 
 #[derive(uniffi::Object)]

From 437bdac923d839775f542aafd4c197d3554164cc Mon Sep 17 00:00:00 2001
From: DanGould <d@ngould.dev>
Date: Fri, 6 Dec 2024 17:28:05 -0500
Subject: [PATCH 2/2] Bump payjoin-ffi 0.21.1

---
 CHANGELOG.md | 3 +++
 Cargo.lock   | 2 +-
 Cargo.toml   | 2 +-
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e751d55..bf8160e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+## [0.21.1]
+- Add `to_json` and `from_json` methods to `Sender` and `Receiver` UniFFI types. ([#39](https://github.com/LtbLightning/payjoin-ffi/pull/39))
+
 ## [0.21.0]
 This release updates the bindings libraries to `payjoin` version `0.21.0`.
 #### APIs changed
diff --git a/Cargo.lock b/Cargo.lock
index 96f89b2..fb0dc26 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2042,7 +2042,7 @@ dependencies = [
 
 [[package]]
 name = "payjoin_ffi"
-version = "0.21.0"
+version = "0.21.1"
 dependencies = [
  "base64 0.22.1",
  "bdk",
diff --git a/Cargo.toml b/Cargo.toml
index e811c98..6fc5536 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "payjoin_ffi"
-version = "0.21.0"
+version = "0.21.1"
 edition = "2021"
 license = "MIT OR Apache-2.0"
 exclude = ["tests"]