Generate Go Bindings

This chances `ParticipantIdentifier` to be represented as a hex
string instead of bytes, because GoLang can use Bytes as a key
for maps [see](NordSecurity/uniffi-bindgen-go#52)

FrostSwift/Sources/FrostSwiftFFI/frost_uniffi_sdk.swift

@@ -946,11 +946,11 @@ public func FfiConverterTypeMessage_lower(_ value: Message) -> RustBuffer {
 
 
 public struct ParticipantIdentifier {
-    public var data: Data
+    public var data: String
 
     // Default memberwise initializers are never public by default, so we
     // declare one manually.
-    public init(data: Data) {
+    public init(data: String) {
         self.data = data
     }
 }
@@ -973,12 +973,12 @@ extension ParticipantIdentifier: Equatable, Hashable {
 public struct FfiConverterTypeParticipantIdentifier: FfiConverterRustBuffer {
     public static func read(from buf: inout (data: Data, offset: Data.Index)) throws -> ParticipantIdentifier {
         return try ParticipantIdentifier(
-            data: FfiConverterData.read(from: &buf)
+            data: FfiConverterString.read(from: &buf)
         )
     }
 
     public static func write(_ value: ParticipantIdentifier, into buf: inout [UInt8]) {
-        FfiConverterData.write(value.data, into: &buf)
+        FfiConverterString.write(value.data, into: &buf)
     }
 }
 

Package.swift

@@ -24,7 +24,7 @@ let package = Package(
                 .target(name: "FrostSwiftFFI")
             ], path: "FrostSwift/Sources/FrostSwift"
         ),
-        .binaryTarget(name: "RustFramework", url: "https://github.com/pacu/frost-uniffi-sdk/releases/download/0.0.1/RustFramework.xcframework.zip", checksum: "c273d33439e052316bb6f78390d124c3dabf6a8f9b99e26525b92057d38bc2f7"),
+        .binaryTarget(name: "RustFramework", path: "FrostSwift/RustFramework.xcframework.zip"),
         .target(
             name: "FrostSwiftFFI",
             dependencies: [

frost-uniffi-sdk/src/lib.rs

@@ -33,7 +33,7 @@ pub struct ParticipantList {
 
 #[derive(uniffi::Record, Hash, Eq, PartialEq, Clone)]
 pub struct ParticipantIdentifier {
-    pub data: Vec<u8>,
+    pub data: String,
 }
 
 #[derive(uniffi::Record)]
@@ -203,16 +203,19 @@ impl FrostKeyPackage {
 impl ParticipantIdentifier {
     pub fn from_identifier(identifier: Identifier) -> Result<ParticipantIdentifier, Error> {
         Ok(ParticipantIdentifier {
-            data: identifier.clone().serialize().to_vec(),
+            data: hex::encode(identifier.clone().serialize()),
         })
     }
 
     pub fn into_identifier(&self) -> Result<Identifier, Error> {
-        let raw_bytes = self.data[0..32]
+        let raw_bytes = hex::decode(self.data.clone())
+            .map_err(|_| Error::DeserializationError)?;
+
+        let raw_identifier = raw_bytes[0..32]
             .try_into()
             .map_err(|_| Error::DeserializationError)?;
 
-        Identifier::deserialize(&raw_bytes)
+        Identifier::deserialize(&raw_identifier)
     }
 }
 

frost-uniffi-sdk/uniffi.toml

@@ -1,4 +1,8 @@
 ## Custom UniFFI binding generation settings
 ## See https://mozilla.github.io/uniffi-rs/swift/configuration.html.  
 #[bindings.kotlin]
-[bindings.swift]
+[bindings.swift]
+
+[bindings.go]
+package_name = "frost_go_ffi"
+module_name = "frost_go_ffi"

frost_go_ffi/frost_go_ffi.c

@@ -0,0 +1,8 @@
+#include <frost_go_ffi.h>
+
+// This file exists beacause of
+// https://github.com/golang/go/issues/11263
+
+void cgo_rust_task_callback_bridge_frost_go_ffi(RustTaskCallback cb, const void * taskData, int8_t status) {
+  cb(taskData, status);
+}