katbin/src/api/catchers/mod.rs

use rocket::http::Status;
use rocket::response::status;
use rocket::Rocket;
use rocket_contrib::json::Json;
use serde_json::Value;

#[catch(404)]
fn not_found() -> status::Custom<Json<Value>> {
    status::Custom(
        Status::NotFound,
        Json(json!({
            "err":"route not found",
            "msg": "The given route does not exist"
        })),
    )
}

#[catch(422)]
fn unprocessable_entity() -> status::Custom<Json<Value>> {
    status::Custom(
        Status::UnprocessableEntity,
        Json(json!({
            "err":"failed to process entity",
            "msg": "The given object could not be processed. This could be due to sending \
             malformed or incomplete JSON objects in the request body."
        })),
    )
}

#[catch(500)]
fn internal_server_error() -> status::Custom<Json<Value>> {
    status::Custom(
        Status::NotFound,
        Json(json!({
            "err":"internal server error",
            "msg": "Something went wrong, try again"
        })),
    )
}

pub fn fuel(rocket: Rocket) -> Rocket {
    rocket.register(catchers![
        not_found,
        unprocessable_entity,
        internal_server_error
    ])
}