Custom JSON Responder for Rocket.io

rocket-json-response.rs

/// # Custom JSON Responder for Rocket.io
///
/// Allow to modify JSON response:
///     - Add custom headers
///     - send cookies
///     - etc...
///
/// # Examples:
///
/// ``` Cargo.toml
/// serde = { version = "1", features = ["derive"] }
/// rocket = { version = "0.5.0-rc.2", features = ["json"] }
/// ```
///
/// ```
/// #[get("/json/with/<string>")]
/// pub fn match_vin<'a>(string: &'a String) -> Json<Vec<String>> {
///
///     let mut strings: Vec<String> = Vec::new();
///
///     items.push(string)
///
///     Json(strings)
/// }
/// ```

use std::io;

use rocket::request::Request;
use rocket::response::{self, Response, Responder};
use rocket::serde::json::{serde_json};
use serde::Serialize;

#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct Json<T>(pub T);


impl<'r, T: Serialize> Responder<'r, 'static> for Json<T> {
    fn respond_to(self, _: &'r Request<'_>) -> response::Result<'static> {

        let string = serde_json::to_string(&self.0)
            .map_err(|e| {
                error_!("JSON failed to serialize: {:?}", e);
                Status::InternalServerError
            })?;

        Response::build()
            .raw_header("Content-Type","application/json; charset=utf-8")
            .raw_header("Cache-Control", "max-age=120")
            .sized_body(string.clone().len(), io::Cursor::new(string))
            .ok()
    }
}