mismatched types expected '&str', found struct 'stdstringString' | Rust Programming Language Community | Page 1

clear cypress Dec 9, 2022, 2:58 PM

#

returning (StatusCode, String) instead would fix this

#

but it would be much better to return an actual error type

#

you could do Cow<'static str> if you want to support both

indigo jasper Dec 9, 2022, 2:59 PM

#

clear cypress returning `(StatusCode, String)` instead would fix this

It would force me to return "some string".to_owned() on others errors, while is not really great ?

clear cypress Dec 9, 2022, 3:01 PM

#

could use Cow

#

but this error is pretty sub optimal

#

designing an error type would be faster, easier and far less error prone

indigo jasper Dec 9, 2022, 3:03 PM

#

how could I do that ? I use Validator to validate my input, and customs errors for the rest

clear cypress Dec 9, 2022, 3:03 PM

#

what is Validate's error type? is it something from a crate you're using?

indigo jasper Dec 9, 2022, 3:03 PM

#

yes

#

https://docs.rs/validator/latest/validator/

validator - Rust

Example:

clear cypress Dec 9, 2022, 3:05 PM

#

at its simplest, you can just wrap it.

#

for example: rust struct MyError{ BadRequest(ValidationError), InternalError(Box<dyn Error>), }

#

and then you could write (assuming you write some minor boilerplate like implementing Error and some From conversions: ```rust
#[axum_macros::debug_handler]
pub async fn update_task(
Path(id): Path<i32>,
Extension(database_conn): Extension<DatabaseConnection>,
Json(request): Json<TaskRequest>,
) -> Result<Json<TaskRequest>, MyError> {

request.validate()?;

let task: Option<tasks::Model> = tasks::Entity::find_by_id(id)
    .one(&database_conn)
    .await
    .map_err(MyError::InternalError)?;```

#mismatched types expected '&str', found struct 'stdstringString'