game_list/backend/src/cached_option.rs

66 lines
1.9 KiB
Rust

use rocket::http::Status;
use rocket::response::Responder;
use rocket::{Request, Response, response};
use std::ops::{FromResidual, Try};
#[derive(Debug)]
pub struct CachedOption(Option<(rocket::http::ContentType, Vec<u8>)>);
impl CachedOption {
fn into_option(self) -> Option<(rocket::http::ContentType, Vec<u8>)> {
self.0
}
}
impl From<Option<(rocket::http::ContentType, Vec<u8>)>> for CachedOption {
fn from(value: Option<(rocket::http::ContentType, Vec<u8>)>) -> Self {
Self(value)
}
}
impl FromResidual<std::option::Option<std::convert::Infallible>> for CachedOption {
fn from_residual(_: std::option::Option<std::convert::Infallible>) -> Self {
Self(None)
}
}
impl FromResidual<CachedOption> for CachedOption {
fn from_residual(residual: CachedOption) -> Self {
residual
}
}
impl Try for CachedOption {
type Output = Option<(rocket::http::ContentType, Vec<u8>)>;
type Residual = Self;
fn from_output(output: Self::Output) -> Self {
Self(output)
}
fn branch(self) -> std::ops::ControlFlow<Self::Residual, Self::Output> {
match self.0 {
Some((ct, bytes)) => std::ops::ControlFlow::Break(Self(Some((ct, bytes)))),
None => std::ops::ControlFlow::Continue(None),
}
}
}
impl<'r> Responder<'r, 'static> for CachedOption {
fn respond_to(self, _: &'r Request<'_>) -> response::Result<'static> {
let option = self.into_option();
if let Some((ct, bytes)) = option {
Response::build()
.header(ct)
.header(rocket::http::Header::new(
"Cache-Control",
"max-age=31536000",
))
.sized_body(bytes.len(), std::io::Cursor::new(bytes))
.ok()
} else {
Err(Status::InternalServerError)
}
}
}