NHibernate.Caches.Redis.RedisCacheProviderOptions.OnUnlockFailed C# (CSharp) Method

        internal void OnUnlockFailed(RedisCache sender, UnlockFailedEventArgs e)
        {
            var onUnlockFailed = UnlockFailed;

            if (onUnlockFailed == null)
            {
                // No-op.
            }
            else
            {
                onUnlockFailed(sender, e);
            }
        }

        /// <summary>
        ///
        /// </summary>
        /// <param name="key"></param>

        public void Unlock(object key)
        {
            // Use Remove() instead of Get() because we are releasing the lock
            // anyways.
            var lockData = _acquiredLocks.Remove(Convert.ToString(key)) as LockData;

            if (lockData == null)
            {
                Log.Warn("attempted to unlock '{0}' but a previous lock was not acquired or timed out", key);
                var unlockFailedEventArgs = new UnlockFailedEventArgs(
                    RegionName, key, lockKey: null, lockValue: null
                    );
                _options.OnUnlockFailed(this, unlockFailedEventArgs);
                return;
            }

            Log.Debug("releasing cache lock: regionName='{0}', key='{1}', lockKey='{2}', lockValue='{3}'",
                      RegionName, lockData.Key, lockData.LockKey, lockData.LockValue
                      );

            try
            {
                var db = GetDatabase();

                // Don't use IDatabase.LockRelease() because it uses watch/unwatch
                // where we prefer an atomic operation (via a script).
                var wasLockReleased = (bool)db.ScriptEvaluate(_unlockScript, new
                {
                    lockKey   = lockData.LockKey,
                    lockValue = lockData.LockValue
                });

                if (!wasLockReleased)
                {
                    Log.Warn("attempted to unlock '{0}' but it could not be released (it maybe timed out or was cleared in Redis)", lockData);

                    var unlockFailedEventArgs = new UnlockFailedEventArgs(
                        RegionName, key, lockData.LockKey, lockData.LockValue
                        );
                    _options.OnUnlockFailed(this, unlockFailedEventArgs);
                }
            }
            catch (Exception e)
            {
                Log.Error("could not release cache lock: regionName='{0}', key='{1}', lockKey='{2}', lockValue='{3}'",
                          RegionName, lockData.Key, lockData.LockKey, lockData.LockValue
                          );

                var evtArg = new ExceptionEventArgs(RegionName, RedisCacheMethod.Unlock, e);
                _options.OnException(this, evtArg);
                if (evtArg.Throw)
                {
                    throw new RedisCacheException(RegionName, "Failed to unlock item in cache. See inner exception.", e);
                }
            }
        }