feat(masking): implement prost::Message trait for Secret and StrongSecret types (#8458)

Co-authored-by: hyperswitch-bot[bot] <148525504+hyperswitch-bot[bot]@users.noreply.github.com>

Cargo.lock

@@ -4729,6 +4729,7 @@ dependencies = [
  "bytes 1.10.1",
  "diesel",
  "erased-serde 0.4.6",
+ "prost",
  "scylla",
  "serde",
  "serde_json",

crates/masking/Cargo.toml

@@ -13,6 +13,8 @@ alloc = ["zeroize/alloc"]
 serde = ["dep:serde", "dep:serde_json"]
 time = ["dep:time"]
 cassandra = ["dep:scylla"]
+proto_tonic = ["dep:bytes", "dep:prost"]
+bytes = ["dep:bytes"]
 
 [package.metadata.docs.rs]
 all-features = true
@@ -29,6 +31,7 @@ time = { version = "0.3.41", optional = true, features = ["serde-human-readable"
 url = { version = "2.5.4", features = ["serde"] }
 zeroize = { version = "1.8", default-features = false }
 scylla = { git = "https://github.com/juspay/scylla-rust-driver.git",rev = "5700aa2847b25437cdd4fcf34d707aa90dca8b89", optional = true}
+prost = { version = "0.13", optional = true }
 
 [dev-dependencies]
 serde_json = "1.0.140"

crates/masking/src/secret.rs

@@ -248,6 +248,38 @@ impl Strategy<serde_json::Value> for JsonMaskStrategy {
     }
 }
 
+#[cfg(feature = "proto_tonic")]
+impl<T> prost::Message for Secret<T, crate::WithType>
+where
+    T: prost::Message + Default + Clone,
+{
+    fn encode_raw(&self, buf: &mut impl bytes::BufMut) {
+        self.peek().encode_raw(buf);
+    }
+
+    fn merge_field(
+        &mut self,
+        tag: u32,
+        wire_type: prost::encoding::WireType,
+        buf: &mut impl bytes::Buf,
+        ctx: prost::encoding::DecodeContext,
+    ) -> Result<(), prost::DecodeError> {
+        if tag == 1 {
+            self.peek_mut().merge_field(tag, wire_type, buf, ctx)
+        } else {
+            prost::encoding::skip_field(wire_type, tag, buf, ctx)
+        }
+    }
+
+    fn encoded_len(&self) -> usize {
+        self.peek().encoded_len()
+    }
+
+    fn clear(&mut self) {
+        self.peek_mut().clear();
+    }
+}
+
 #[cfg(test)]
 #[cfg(feature = "serde")]
 mod tests {

crates/masking/src/strong_secret.rs

@@ -126,3 +126,35 @@ impl StrongEq for Vec<u8> {
         bool::from(lhs.ct_eq(rhs))
     }
 }
+
+#[cfg(feature = "proto_tonic")]
+impl<T> prost::Message for StrongSecret<T, crate::WithType>
+where
+    T: prost::Message + Default + Clone + ZeroizableSecret,
+{
+    fn encode_raw(&self, buf: &mut impl bytes::BufMut) {
+        self.peek().encode_raw(buf);
+    }
+
+    fn merge_field(
+        &mut self,
+        tag: u32,
+        wire_type: prost::encoding::WireType,
+        buf: &mut impl bytes::Buf,
+        ctx: prost::encoding::DecodeContext,
+    ) -> Result<(), prost::DecodeError> {
+        if tag == 1 {
+            self.peek_mut().merge_field(tag, wire_type, buf, ctx)
+        } else {
+            prost::encoding::skip_field(wire_type, tag, buf, ctx)
+        }
+    }
+
+    fn encoded_len(&self) -> usize {
+        self.peek().encoded_len()
+    }
+
+    fn clear(&mut self) {
+        self.peek_mut().clear();
+    }
+}