[OPTIMIZATION] rate limter

Cargo.toml

@@ -17,6 +17,7 @@ clap = "2.33"
 cookie = "0.14"
 futures = "0.3"
 futures-util = "0.3"
+fnv = "1.0.7"
 gethostname = "0.2"
 http-auth-basic = "0.1"
 hyper = { version = "0.14", features = ["client", "server", "http1", "http2", "stream"] }
@@ -27,6 +28,7 @@ linked-hash-map = "0.5"
 lazy_static = "1.4"
 log = "0.4"
 log4rs = "1.0"
+lru = "0.12.0"
 notify = "4.0"
 openssl-sys = { version = "0.9", features = ["vendored"] }
 pin-project = "1.0"
@@ -42,6 +44,5 @@ tokio-util = { version = "0.6", features = ["full"] }
 toml = { version = "0.5", features = ["preserve_order"] }
 url = "2.2"
 warp = "0.3.6"
-fnv = "1.0.7"
 
 [build-dependencies]

src/middleware/rate_limiter.rs

@@ -28,26 +28,20 @@ impl RateLimiter {
 
     let old_entries = connections
       .iter()
-      // Due to temporal order in LinkedHashMap stopping early is possible
       .take_while(|(_client_address, (_count, time))| now.duration_since(*time).as_secs() > self.window_sec)
       .map(|(client_address, _)| *client_address)
       .collect::<Vec<_>>();
     for client_address in old_entries {
       connections.remove(&client_address);
     }
 
-    // Remove and reinsert to ensure temporal order in LinkedHashMap
-    let mut count = connections
-      .remove(client_address)
-      .map(|(count, _time)| count)
-      .unwrap_or(0);
-    // Prevent overflow
-    if count < u64::MAX {
-      count += 1;
-    }
-    connections.insert(*client_address, (count, now));
+    let count = connections
+      .entry(*client_address)
+      .or_insert((0, now));
+    count.0 += 1;
+    count.1 = now;
 
-    count <= self.limit
+    count.0 <= self.limit
   }
 }