通过遵守这些指南，您可以有效地管理数据结构的演变，同时确保版本间的无缝迁移。

设置 - 向您的结构体添加属性

use serde_flow::{Flow};
use serde::{Deserialize, Serialize};

// The last (variant 3) of the User
#[derive(Serialize, Deserialize, Flow)]
#[flow(variant = 3, file)]
#[variants(UserV1, UserV2)]
pub struct User {
    pub first_name: String,
    pub middle_name: String,
    pub last_name: String,
}

// previous variant
#[derive(Serialize, Deserialize, Flow)]
#[flow(variant = 2)]
pub struct UserV2 {
    pub first_name: String,
    pub last_name: String,
}

// the first variant of the User entity
#[derive(Serialize, Deserialize, Flow)]
#[flow(variant = 1)]
pub struct UserV1 {
    pub name: String,
}

// Migration from UserV1 and UserV2 for User
impl From<UserV1> for User { /* migration */ }
impl From<UserV2> for User { /* migration */ }

用法

use serde_flow::{encoder::bincode, flow::File, flow::FileMigrate, Flow};

// create an old struct UserV2
let user_v2 = UserV2 {
    name: "John Adam Doe".to_string(),
};

// serialize to the disk
user_v2
    .save_to_path::<bincode::Encoder>(&Path::new("/path/to/user"))
    .unwrap();

// deserialize as User
let user = User::load_from_path::<bincode::Encoder>(path.as_path()).unwrap();

// Migrate and load (loads, migrates, saves, and returns new entity)
let user User::load_and_migrate::<bincode::Encoder>(path.as_path()).unwrap();

// Just migrate (loads, migrates, and saves new entity)
User::migrate::<bincode::Encoder>(path.as_path()).unwrap();

📜 许可证

Serde-flow 是开源软件，在 MIT 许可证下免费提供。