Serde没有为Rocket的UUID实现Serialize。

8

我正在尝试创建一个自定义结构体,其中包含 Rocket 的 UUID 结构体。我希望使用 Serde 进行序列化,以便于将其轻松转换为 JSON 格式。

但是在尝试这样做时,我遇到了一个错误:

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`

我的结构体:

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

我的导入:

[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"]

我使用结构体的端点:

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

我已经检查过所有依赖项,并在rocket_contrib中启用了serde功能。我已经没有更多的想法要检查了。

1个回答

10

rocket_contrib::UUID并未实现 Serialize:

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

如果类型没有实现Serialize,你就不能制作它。
正如mcarton指出的那样:

你仍然可以为你的类型实现Serialize,你只需要手动实现它,而无法自动派生。

这可能看起来像:
#[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)
    }
}

相关链接:


1
@Mestru 注意,您仍然可以为您的类型实现 Serialize,但是您无法派生它,必须手动实现它。 - mcarton

网页内容由stack overflow 提供, 点击上面的
可以查看英文原文,
原文链接