Cache icons on the client

This should make the vault pages load much faster, and massively reduce the number of requests.

src/api/icons.rs

@@ -51,7 +51,10 @@ fn icon(domain: String) -> Option<Cached<Content<Vec<u8>>>> {
         return None;
     }
 
-    get_icon(&domain).map(|icon| Cached::long(Content(ContentType::new("image", "x-icon"), icon)))
+    get_icon(&domain).map(|(icon, cached)| {
+        let cache_ttl = if cached {CONFIG.icon_cache_ttl()} else {CONFIG.icon_cache_negttl()};
+        Cached::ttl(Content(ContentType::new("image", "x-icon"), icon), cache_ttl)
+    })
 }
 
 /// Returns if the domain provided is valid or not.
@@ -238,7 +241,7 @@ fn is_domain_blacklisted(domain: &str) -> bool {
     is_blacklisted
 }
 
-fn get_icon(domain: &str) -> Option<Vec<u8>> {
+fn get_icon(domain: &str) -> Option<(Vec<u8>, bool)> {
     let path = format!("{}/{}.png", CONFIG.icon_cache_folder(), domain);
 
     // Check for expiration of negatively cached copy
@@ -247,7 +250,7 @@ fn get_icon(domain: &str) -> Option<Vec<u8>> {
     }
 
     if let Some(icon) = get_cached_icon(&path) {
-        return Some(icon);
+        return Some((icon, true));
     }
 
     if CONFIG.disable_icon_download() {
@@ -258,7 +261,7 @@ fn get_icon(domain: &str) -> Option<Vec<u8>> {
     match download_icon(&domain) {
         Ok(icon) => {
             save_icon(&path, &icon);
-            Some(icon)
+            Some((icon, false))
         }
         Err(e) => {
             error!("Error downloading icon: {:?}", e);

src/util.rs

@@ -92,17 +92,21 @@ impl Fairing for CORS {
     }
 }
 
-pub struct Cached<R>(R, &'static str);
+pub struct Cached<R>(R, String);
 
 impl<R> Cached<R> {
-    pub const fn long(r: R) -> Cached<R> {
+    pub fn long(r: R) -> Cached<R> {
         // 7 days
-        Self(r, "public, max-age=604800")
+        Self(r, String::from("public, max-age=604800"))
     }
 
-    pub const fn short(r: R) -> Cached<R> {
+    pub fn short(r: R) -> Cached<R> {
         // 10 minutes
-        Self(r, "public, max-age=600")
+        Self(r, String::from("public, max-age=600"))
+    }
+
+    pub fn ttl(r: R, ttl: u64) -> Cached<R> {
+        Self(r, format!("public, immutable, max-age={}", ttl))
     }
 }