Files
bevy/examples/reflection/serialization.rs
T
Giacomo Stevanato b7b8fa4ccc TypedReflectDeserializer: return a concrete value when possible (#21137)
# Objective

- This is another way to fix to #20952
- It also fixes any other user of `TypedReflectDeserializer` that was
expecting a concrete type being returned.

## Solution

- Attempt to use the reflected `FromReflect` to produce a concrete type
after deserializing a dynamic value.

## Testing

- I added a slightly modified test from #20981 to demonstrate that this
also fixes the issue. I'll probably rebase this once #20981 lands
though.

---------

Co-authored-by: François Mockers <francois.mockers@vleue.com>
2025-09-21 20:42:57 +00:00

66 lines
1.9 KiB
Rust

//! Illustrates how "reflection" serialization works in Bevy.
//!
//! Deriving `Reflect` will also register `SerializationData`,
//! which powers reflect (de)serialization.
//! Serializing reflected data *does not* require deriving serde's
//! Serialize and Deserialize implementations.
use bevy::{
prelude::*,
reflect::serde::{ReflectDeserializer, ReflectSerializer},
};
use serde::de::DeserializeSeed;
fn main() {
App::new()
.add_plugins(DefaultPlugins)
.add_systems(Startup, (deserialize, serialize).chain())
.run();
}
/// Deriving `Reflect` includes reflecting `SerializationData`
#[derive(Reflect)]
pub struct Player {
name: String,
health: u32,
}
const PLAYER_JSON: &str = r#"{
"serialization::Player": {
"name": "BevyPlayerOne",
"health": 50
}
}"#;
fn deserialize(type_registry: Res<AppTypeRegistry>) {
let type_registry = type_registry.read();
// a serde_json::Value that might have come from an API
let value: serde_json::Value = serde_json::from_str(PLAYER_JSON).unwrap();
// alternatively, `TypedReflectDeserializer` can be used if the type
// is known.
let deserializer = ReflectDeserializer::new(&type_registry);
// deserialize
let reflect_value = deserializer.deserialize(value).unwrap();
// If Player implemented additional functionality, like Component,
// this reflect_value could be used with commands.insert_reflect
info!(?reflect_value);
}
fn serialize(type_registry: Res<AppTypeRegistry>) {
let type_registry = type_registry.read();
// a concrete value
let value = Player {
name: "BevyPlayerSerialize".to_string(),
health: 80,
};
// By default, all derived `Reflect` types can be serialized using serde. No need to derive
// Serialize!
let serializer = ReflectSerializer::new(&value, &type_registry);
let json = serde_json::to_string(&serializer).unwrap();
info!(?json);
}