Migrate lazy_static to once_cell, less macro magic and slightly faster

src/api/admin.rs

@@ -1,3 +1,4 @@
+use once_cell::sync::Lazy;
 use serde_json::Value;
 use std::process::Command;
 
@@ -38,9 +39,8 @@ pub fn routes() -> Vec<Route> {
     ]
 }
 
-lazy_static! {
-    static ref CAN_BACKUP: bool = cfg!(feature = "sqlite") && Command::new("sqlite3").arg("-version").status().is_ok();
-}
+static CAN_BACKUP: Lazy<bool> =
+    Lazy::new(|| cfg!(feature = "sqlite") && Command::new("sqlite3").arg("-version").status().is_ok());
 
 #[get("/")]
 fn admin_disabled() -> &'static str {

src/api/core/two_factor/u2f.rs

@@ -1,3 +1,4 @@
+use once_cell::sync::Lazy;
 use rocket::Route;
 use rocket_contrib::json::Json;
 use serde_json;
@@ -18,10 +19,8 @@ use crate::CONFIG;
 
 const U2F_VERSION: &str = "U2F_V2";
 
-lazy_static! {
-    static ref APP_ID: String = format!("{}/app-id.json", &CONFIG.domain());
-    static ref U2F: U2f = U2f::new(APP_ID.clone());
-}
+static APP_ID: Lazy<String> = Lazy::new(|| format!("{}/app-id.json", &CONFIG.domain()));
+static U2F: Lazy<U2f> = Lazy::new(|| U2f::new(APP_ID.clone()));
 
 pub fn routes() -> Vec<Route> {
     routes![

src/api/icons.rs

@@ -1,3 +1,4 @@
+use once_cell::sync::Lazy;
 use std::fs::{create_dir_all, remove_file, symlink_metadata, File};
 use std::io::prelude::*;
 use std::net::ToSocketAddrs;
@@ -26,16 +27,16 @@ const FALLBACK_ICON: &[u8; 344] = include_bytes!("../static/fallback-icon.png");
 
 const ALLOWED_CHARS: &str = "_-.";
 
-lazy_static! {
+static CLIENT: Lazy<Client> = Lazy::new(|| {
     // Reuse the client between requests
-    static ref CLIENT: Client = Client::builder()
+    Client::builder()
         .use_sys_proxy()
         .gzip(true)
         .timeout(Duration::from_secs(CONFIG.icon_download_timeout()))
         .default_headers(_header_map())
         .build()
-        .unwrap();
-}
+        .unwrap()
+});
 
 fn is_valid_domain(domain: &str) -> bool {
     // Don't allow empty or too big domains or path traversal