add #[serde(default)] to msg types

allows skipping fields when deserializing from json.

Cargo.toml

@@ -1,7 +1,7 @@
 
 [package]
 name = "r2r"
-version = "0.6.0"
+version = "0.6.1"
 authors = ["Martin Dahl <martin.dahl@gmail.com>"]
 description = "Easy to use, runtime-agnostic, async rust bindings for ROS2."
 license = "MIT AND Apache-2.0"
@@ -21,7 +21,7 @@ thiserror = "1.0.30"
 lazy_static = "1.4.0"
 r2r_common = { path = "r2r_common", version = "0.3.0" }
 r2r_rcl = { path = "r2r_rcl", version = "0.3.0" }
-r2r_msg_gen = { path = "r2r_msg_gen", version = "0.3.0" }
+r2r_msg_gen = { path = "r2r_msg_gen", version = "0.3.1" }
 r2r_actions = { path = "r2r_actions", version = "0.3.0" }
 uuid = { version = "0.8.2", features = ["serde", "v4"] }
 retain_mut = "0.1.5"
@@ -35,6 +35,6 @@ rand = "0.8.4"
 
 [build-dependencies]
 r2r_common = { path = "r2r_common", version = "0.3.0" }
-r2r_msg_gen = { path = "r2r_msg_gen", version = "0.3.0" }
+r2r_msg_gen = { path = "r2r_msg_gen", version = "0.3.1" }
 
 [workspace]

r2r_msg_gen/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "r2r_msg_gen"
-version = "0.3.0"
+version = "0.3.1"
 authors = ["Martin Dahl <martin.dahl@gmail.com>"]
 description = "Internal dependency to the r2r crate."
 license = "MIT"

r2r_msg_gen/src/lib.rs

@@ -494,6 +494,7 @@ pub fn generate_rust_msg(module_: &str, prefix_: &str, name_: &str) -> String {
         let module_str = format!(
             "
                           #[derive(Clone,Debug,PartialEq,Serialize,Deserialize)]
+                          #[serde(default)]
                           pub struct {msgname} {{\n
                               {fields}
                           }}\n

src/msg_types.rs

@@ -583,6 +583,36 @@ mod tests {
         assert_eq!(msg, msg2);
     }
 
+    #[cfg(r2r__test_msgs__msg__Defaults)]
+    #[test]
+    fn test_untyped_json_default() {
+        // from the msg definition file:
+        // bool bool_value true
+        // byte byte_value 50
+        // char char_value 100
+        // float32 float32_value 1.125
+        // ...
+
+        // let's try to change only a few fields.
+        let json = r#"
+        {
+            "byte_value": 255,
+            "float32_value": 3.14
+        }"#;
+
+        let mut native =
+            WrappedNativeMsgUntyped::new_from("test_msgs/msg/Defaults").unwrap();
+        let v: serde_json::Value = serde_json::from_str(json).unwrap();
+        native.from_json(v).expect("could make default msg");
+        let json2 = native.to_json().unwrap();
+        let msg2: test_msgs::msg::Defaults = serde_json::from_value(json2).unwrap();
+
+        assert_eq!(msg2.bool_value, true); // the default
+        assert_eq!(msg2.byte_value, 255); // from our json
+        assert_eq!(msg2.char_value, 100); // the default
+        assert_eq!(msg2.float32_value, 3.14); // from our json
+    }
+
     #[cfg(r2r__test_msgs__msg__Arrays)]
     #[test]
     fn test_test_msgs_array() -> () {