找不到针对Rocket的UUID的Serde的序列化实现

Question

我正在尝试使用UUIDRocket中的结构作为字段类型来创建自定义结构。我希望使用Serde将其序列化，以便轻松将其转换为JSON。

尝试执行此操作时，出现错误：

error[E0277]: the trait bound `rocket_contrib::UUID: 
model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::Serialize` is not 
satisfied
 --> src/service/document.rs:4:10
  |
4 | #[derive(Serialize, Deserialize)]
  |          ^^^^^^^^^ the trait 
`model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::Serialize` is not 
implemented for `rocket_contrib::UUID`
  |
  = note: required by `model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::ser::SerializeStruct::serialize_field`

error[E0277]: the trait bound `rocket_contrib::UUID: 
model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::Deserialize<'_>` is not satisfied
 --> src/service/document.rs:4:21
  |
4 | #[derive(Serialize, Deserialize)]
  |                     ^^^^^^^^^^^ the trait 
`model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::Deserialize<'_>` is not implemented for `rocket_contrib::UUID`
  |
  = note: required by `model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::de::SeqAccess::next_element`

error[E0277]: the trait bound `rocket_contrib::UUID: model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::Deserialize<'_>` is not satisfied
 --> src/service/document.rs:4:21
  |
4 | #[derive(Serialize, Deserialize)]
  |                     ^^^^^^^^^^^ the trait `model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::Deserialize<'_>` is not implemented for `rocket_contrib::UUID`
  |
  = note: required by `model::event::_IMPL_DESERIALIZE_FOR_Event::_serde::de::MapAccess::next_value`

我的结构：

#[derive(Serialize, Deserialize)]
pub struct Document {
    id: UUID,
    user_id: UUID,
    created: i64,
    updated: i64,
    text: String
}

我的进口：

[dependencies]
rocket = "0.3.17"
rocket_codegen = "0.3.17"

serde_derive = "1.0.80"
serde = "1.0.80"

chrono = "0.4"

[dependencies.rocket_contrib]
version = "0.3.17"
default-features = false
features = ["json", "uuid", "serde"]

我使用该结构的端点：

#[get("/document/<id>")]
pub fn get_document(id: UUID) -> status::Accepted<Json<Document>> {
    status::Accepted(Some(Json(document::get_document(id))))
}

我已经检查了所有依赖项，并在中serde启用了该功能rocket_contrib。我已经用尽了下一步要检查的想法。

Answer 1

rocket_contrib::UUID并没有实现Serialize：

#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Debug)]
pub struct UUID(uuid_ext::Uuid);

如果类型未实现Serialize，则无法实现。

正如麦卡顿指出：

您仍然可以为您的类型实现 Serialize，您根本无法派生它，而必须手动实现。

可能看起来像：

#[derive(Serialize, Deserialize)]
pub struct Document {
    #[serde(with = "my_uuid")]
    id: UUID,
    #[serde(with = "my_uuid")]
    user_id: UUID,
    created: i64,
    updated: i64,
    text: String,
}

mod my_uuid {
    use rocket_contrib::UUID;
    use serde::{de::Error, Deserialize, Deserializer, Serialize, Serializer};
    use std::str::FromStr;

    pub fn serialize<S>(val: &UUID, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        val.to_string().serialize(serializer)
    }

    pub fn deserialize<'de, D>(deserializer: D) -> Result<UUID, D::Error>
    where
        D: Deserializer<'de>,
    {
        let val: &str = Deserialize::deserialize(deserializer)?;
        UUID::from_str(val).map_err(D::Error::custom)
    }
}

也可以看看：

• 如何使用Serde在序列化期间转换字段？
• 如何使用Serde在反序列化期间转换字段？
• 有没有一种方法可以对库的结构或枚举使用＃[derive]而无需编辑实际库的源代码？
• 如何为我不拥有的类型实现我不拥有的特征？
• 添加序列化属性以从第三方库键入