def _try_to_evict_one_entry()

in src/aws_encryption_sdk/caches/local.py [0:0]

• 17 lines of code
• 7 McCabe index (conditional complexity)

    def _try_to_evict_one_entry(self):
        """Checks the least recently evaluated entry and evicts it from the cache if it is expired."""
        with self._cache_lock:
            try:
                entry_ref = self._lre_deque.pop()
            except IndexError:
                # LRE deque is empty
                return
            actual_entry = entry_ref()
            if actual_entry is None:
                # actual entry has already been removed
                return
            if not actual_entry.valid or actual_entry.is_too_old():
                # remove from cache
                actual_entry.invalidate()
                try:
                    del self._cache[actual_entry.cache_key]
                except KeyError:
                    # Catches a race condition where entries removed by _prune
                    # may not be garbage collected as quickly as manually removed
                    # entries
                    pass
                return
            # entry is still active and valid: add back to start of LRE
            self._lre_deque.appendleft(entry_ref)