rkyv的特质对象序列化。

资源

学习资料

• rkyv 书籍 涵盖了rkyv的动机、架构和主要功能
• rkyv discord 是获取特定问题帮助和结识其他使用rkyv的人的好地方

文档

• rkyv，核心库
• rkyv_dyn，为rkyv添加特质对象支持
• rkyv_typename，一个类型命名库

基准测试

• rust序列化基准 是一种对决风格的基准，比较了许多Rust序列化解决方案。它包括针对rkyv等零拷贝序列化解决方案的特殊基准。

姐妹crate

• bytecheck，rkyv用于验证
• ptr_meta，rkyv用于指针操作
• rend，rkyv用于端无关功能

示例

use rkyv::{
    archived_value,
    ser::{
        serializers::AllocSerializer,
        Serializer,
    },
    Archive,
    Archived,
    Deserialize,
    Infallible,
    Serialize,
};
use rkyv_dyn::archive_dyn;
use rkyv_typename::TypeName;

#[archive_dyn(deserialize)]
trait ExampleTrait {
    fn value(&self) -> String;
}

#[derive(Archive, Serialize, Deserialize)]
#[archive_attr(derive(TypeName))]
struct StringStruct(String);

#[archive_dyn(deserialize)]
impl ExampleTrait for StringStruct {
    fn value(&self) -> String {
        self.0.clone()
    }
}

impl ExampleTrait for Archived<StringStruct> {
    fn value(&self) -> String {
        self.0.as_str().to_string()
    }
}

#[derive(Archive, Serialize, Deserialize)]
#[archive_attr(derive(TypeName))]
struct IntStruct(i32);

#[archive_dyn(deserialize)]
impl ExampleTrait for IntStruct {
    fn value(&self) -> String {
        format!("{}", self.0)
    }
}

impl ExampleTrait for Archived<IntStruct> {
    fn value(&self) -> String {
        format!("{}", self.0)
    }
}

#[test]
fn main() {
    let boxed_int = Box::new(IntStruct(42)) as Box<dyn SerializeExampleTrait>;
    let boxed_string = Box::new(StringStruct("hello world".to_string())) as Box<dyn SerializeExampleTrait>;
    let mut serializer = AllocSerializer::<256>::default();

    let int_pos = serializer.serialize_value(&boxed_int).unwrap();
    let string_pos = serializer.serialize_value(&boxed_string).unwrap();
    let buf = serializer.into_serializer().into_inner();

    let archived_int = unsafe { archived_value::<Box<dyn SerializeExampleTrait>>(buf.as_ref(), int_pos) };
    let archived_string = unsafe { archived_value::<Box<dyn SerializeExampleTrait>>(buf.as_ref(), string_pos) };
    assert_eq!(archived_int.value(), "42");
    assert_eq!(archived_string.value(), "hello world");

    let deserialized_int: Box<dyn SerializeExampleTrait> = archived_int.deserialize(&mut Infallible).unwrap();
    let deserialized_string: Box<dyn SerializeExampleTrait> = archived_string.deserialize(&mut Infallible).unwrap();
    assert_eq!(deserialized_int.value(), "42");
    assert_eq!(deserialized_string.value(), "hello world");
}