Adaptive Buffers + Session Eviction Method

src/proxy/session_eviction.rs

@@ -0,0 +1,46 @@
+/// Session eviction is intentionally disabled in runtime.
+///
+/// The initial `user+dc` single-lease model caused valid parallel client
+/// connections to evict each other. Keep the API shape for compatibility,
+/// but make it a no-op until a safer policy is introduced.
+
+#[derive(Debug, Clone, Default)]
+pub struct SessionLease;
+
+impl SessionLease {
+    pub fn is_stale(&self) -> bool {
+        false
+    }
+
+    #[allow(dead_code)]
+    pub fn release(&self) {}
+}
+
+pub struct RegistrationResult {
+    pub lease: SessionLease,
+    pub replaced_existing: bool,
+}
+
+pub fn register_session(_user: &str, _dc_idx: i16) -> RegistrationResult {
+    RegistrationResult {
+        lease: SessionLease,
+        replaced_existing: false,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_session_eviction_disabled_behavior() {
+        let first = register_session("alice", 2);
+        let second = register_session("alice", 2);
+        assert!(!first.replaced_existing);
+        assert!(!second.replaced_existing);
+        assert!(!first.lease.is_stale());
+        assert!(!second.lease.is_stale());
+        first.lease.release();
+        second.lease.release();
+    }
+}