rust - 如何使用actix-web的Json类型解析 "implementation of serde::Deserialize is not general enough"？

我正在使用actix-web编写服务器:

use actix_web::{post, web, Responder};
use serde::Deserialize;

#[derive(Deserialize)]
struct UserModel<'a, 'b> {
    username: &'a str,
    password: &'b str,
}

#[post("/")]
pub fn register(user_model: web::Json<UserModel>) -> impl Responder {}

编译器给出此错误:

error: implementation of `user::_IMPL_DESERIALIZE_FOR_UserModel::_serde::Deserialize` is not general enough
  --> src/user.rs:31:1
   |
31 | #[post("/")]
   | ^^^^^^^^^^^^
   |
   = note: `user::UserModel<'_, '_>` must implement `user::_IMPL_DESERIALIZE_FOR_UserModel::_serde::Deserialize<'0>`, for any lifetime `'0`
   = note: but `user::UserModel<'_, '_>` actually implements `user::_IMPL_DESERIALIZE_FOR_UserModel::_serde::Deserialize<'1>`, for some specific lifetime `'1`

我该如何解决？

最佳答案

从the actix-web documentation:

impl<T> FromRequest for Json<T>
where
    T: DeserializeOwned + 'static,

它基本上说，如果您希望Json从请求中提取类型，则只能使用actix-web类型的拥有的数据，而不能借用数据。因此，您必须在此处使用String:

use actix_web::{post, web, Responder};
use serde::Deserialize;

#[derive(Deserialize)]
struct UserModel {
    username: String,
    password: String,
}

#[post("/")]
pub fn register(user_model: web::Json<UserModel>) -> impl Responder {
    unimplemented!()
}

关于rust - 如何使用actix-web的Json类型解析 "implementation of serde::Deserialize is not general enough"？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/57976096/