// An arbitrary `Cache-Control` headers functionality for incoming requests based on a set of file types. use headers::{CacheControl, HeaderMapExt}; use hyper::{Body, Response}; // Cache-Control `max-age` variants const MAX_AGE_ONE_HOUR: u64 = 60 * 60; const MAX_AGE_ONE_DAY: u64 = 60 * 60 * 24; const MAX_AGE_ONE_YEAR: u64 = 60 * 60 * 24 * 365; // `Cache-Control` list of extensions const CACHE_EXT_ONE_HOUR: [&str; 4] = ["atom", "json", "rss", "xml"]; const CACHE_EXT_ONE_YEAR: [&str; 32] = [ "avif", "bmp", "bz2", "css", "doc", "gif", "gz", "htc", "ico", "jpeg", "jpg", "js", "jxl", "map", "mjs", "mp3", "mp4", "ogg", "ogv", "pdf", "png", "rar", "rtf", "tar", "tgz", "wav", "weba", "webm", "webp", "woff", "woff2", "zip", ]; /// It appends a `Cache-Control` header to a response if that one is part of a set of file types. pub fn append_headers(uri: &str, resp: &mut Response) { // Default max-age value in seconds (one day) let mut max_age = MAX_AGE_ONE_DAY; if CACHE_EXT_ONE_HOUR .iter() .any(|x| uri.ends_with(&[".", *x].concat())) { max_age = MAX_AGE_ONE_HOUR; } else if CACHE_EXT_ONE_YEAR .iter() .any(|x| uri.ends_with(&[".", *x].concat())) { max_age = MAX_AGE_ONE_YEAR; } let cache_control = CacheControl::new() .with_public() .with_max_age(duration_from_secs(max_age)); resp.headers_mut().typed_insert(cache_control); } /// It caps a duration value at ~136 years. fn duration_from_secs(secs: u64) -> std::time::Duration { std::time::Duration::from_secs(std::cmp::min(secs, u32::MAX as u64)) } #[cfg(test)] mod tests { use hyper::{Body, Response, StatusCode}; use super::{ append_headers, CACHE_EXT_ONE_HOUR, CACHE_EXT_ONE_YEAR, MAX_AGE_ONE_DAY, MAX_AGE_ONE_HOUR, MAX_AGE_ONE_YEAR, }; #[tokio::test] async fn headers_one_hour() { let mut resp = Response::new(Body::empty()); *resp.status_mut() = StatusCode::OK; for ext in CACHE_EXT_ONE_HOUR.iter() { append_headers(&["/some.", ext].concat(), &mut resp); let cache_control = resp.headers().get(http::header::CACHE_CONTROL).unwrap(); assert_eq!(resp.status(), StatusCode::OK); assert_eq!( cache_control.to_str().unwrap(), format!("public, max-age={MAX_AGE_ONE_HOUR}") ); } } #[tokio::test] async fn headers_one_day_default() { let mut resp = Response::new(Body::empty()); *resp.status_mut() = StatusCode::OK; append_headers("/", &mut resp); let cache_control = resp.headers().get(http::header::CACHE_CONTROL).unwrap(); assert_eq!(resp.status(), StatusCode::OK); assert_eq!( cache_control.to_str().unwrap(), format!("public, max-age={MAX_AGE_ONE_DAY}") ); } #[tokio::test] async fn headers_one_year() { let mut resp = Response::new(Body::empty()); *resp.status_mut() = StatusCode::OK; for ext in CACHE_EXT_ONE_YEAR.iter() { append_headers(&["/some.", ext].concat(), &mut resp); let cache_control = resp.headers().get(http::header::CACHE_CONTROL).unwrap(); assert_eq!(resp.status(), StatusCode::OK); assert_eq!( cache_control.to_str().unwrap(), format!("public, max-age={MAX_AGE_ONE_YEAR}") ); } } }