/// <summary>
/// Checks if any of the follower servers need refresh.
/// If so, a neighborhood action is created.
/// </summary>
public async Task CheckFollowersRefreshAsync()
{
log.Trace("()");
// If a follower server's LastRefreshTime is lower than this limit, it should be refreshed.
DateTime limitLastRefreshTime = DateTime.UtcNow.AddSeconds(-Config.Configuration.FollowerRefreshTimeSeconds);
using (UnitOfWork unitOfWork = new UnitOfWork())
{
DatabaseLock[] lockObjects = new DatabaseLock[] { UnitOfWork.FollowerLock, UnitOfWork.NeighborhoodActionLock };
await unitOfWork.AcquireLockAsync(lockObjects);
try
{
List <Follower> followersToRefresh = (await unitOfWork.FollowerRepository.GetAsync(f => f.LastRefreshTime < limitLastRefreshTime, null, true)).ToList();
if (followersToRefresh.Count > 0)
{
log.Debug("There are {0} followers that need refresh.", followersToRefresh.Count);
foreach (Follower follower in followersToRefresh)
{
NeighborhoodAction action = new NeighborhoodAction()
{
ServerId = follower.FollowerId,
Type = NeighborhoodActionType.RefreshProfiles,
Timestamp = DateTime.UtcNow,
ExecuteAfter = DateTime.UtcNow,
TargetIdentityId = null,
AdditionalData = null
};
await unitOfWork.NeighborhoodActionRepository.InsertAsync(action);
log.Debug("Refresh neighborhood action for follower ID '{0}' will be inserted to the database.", follower.FollowerId.ToHex());
}
await unitOfWork.SaveThrowAsync();
log.Debug("{0} new neighborhood actions saved to the database.", followersToRefresh.Count);
}
else
{
log.Debug("No followers need refresh now.");
}
}
catch (Exception e)
{
log.Error("Exception occurred: {0}", e.ToString());
}
unitOfWork.ReleaseLock(lockObjects);
}
log.Trace("(-)");
}
/// <summary>
/// Checks if any of the neighbors expired.
/// If so, it starts the process of their removal.
/// </summary>
public async Task CheckExpiredNeighborsAsync()
{
log.Trace("()");
// If a neighbor server's LastRefreshTime is lower than this limit, it is expired.
DateTime limitLastRefreshTime = DateTime.UtcNow.AddSeconds(-Config.Configuration.NeighborProfilesExpirationTimeSeconds);
using (UnitOfWork unitOfWork = new UnitOfWork())
{
bool success = false;
DatabaseLock[] lockObjects = new DatabaseLock[] { UnitOfWork.NeighborLock, UnitOfWork.NeighborhoodActionLock };
using (IDbContextTransaction transaction = await unitOfWork.BeginTransactionWithLockAsync(lockObjects))
{
try
{
List <Neighbor> expiredNeighbors = (await unitOfWork.NeighborRepository.GetAsync(n => n.LastRefreshTime < limitLastRefreshTime, null, true)).ToList();
if (expiredNeighbors.Count > 0)
{
log.Debug("There are {0} expired neighbors.", expiredNeighbors.Count);
foreach (Neighbor neighbor in expiredNeighbors)
{
// This action will cause our profile server to erase all profiles of the neighbor that has been removed.
NeighborhoodAction action = new NeighborhoodAction()
{
ServerId = neighbor.NeighborId,
Timestamp = DateTime.UtcNow,
Type = NeighborhoodActionType.RemoveNeighbor,
TargetIdentityId = null,
AdditionalData = null
};
await unitOfWork.NeighborhoodActionRepository.InsertAsync(action);
}
await unitOfWork.SaveThrowAsync();
transaction.Commit();
}
else
{
log.Debug("No expired neighbors found.");
}
success = true;
}
catch (Exception e)
{
log.Error("Exception occurred: {0}", e.ToString());
}
if (!success)
{
log.Warn("Rolling back transaction.");
unitOfWork.SafeTransactionRollback(transaction);
}
unitOfWork.ReleaseLock(lockObjects);
}
}
log.Trace("(-)");
}
/// <summary>
/// Checks if any of the hosted identities expired.
/// If so, it deletes them.
/// </summary>
public async Task CheckExpiredHostedIdentitiesAsync()
{
log.Trace("()");
DateTime now = DateTime.UtcNow;
List <byte[]> imagesToDelete = new List <byte[]>();
using (UnitOfWork unitOfWork = new UnitOfWork())
{
// Disable change tracking for faster multiple deletes.
unitOfWork.Context.ChangeTracker.AutoDetectChangesEnabled = false;
DatabaseLock lockObject = UnitOfWork.HostedIdentityLock;
await unitOfWork.AcquireLockAsync(lockObject);
try
{
List <HostedIdentity> expiredIdentities = (await unitOfWork.HostedIdentityRepository.GetAsync(i => i.ExpirationDate < now, null, true)).ToList();
if (expiredIdentities.Count > 0)
{
log.Debug("There are {0} expired hosted identities.", expiredIdentities.Count);
foreach (HostedIdentity identity in expiredIdentities)
{
if (identity.ProfileImage != null)
{
imagesToDelete.Add(identity.ProfileImage);
}
if (identity.ThumbnailImage != null)
{
imagesToDelete.Add(identity.ThumbnailImage);
}
unitOfWork.HostedIdentityRepository.Delete(identity);
log.Debug("Identity ID '{0}' expired and will be deleted.", identity.IdentityId.ToHex());
}
await unitOfWork.SaveThrowAsync();
log.Debug("{0} expired hosted identities were deleted.", expiredIdentities.Count);
}
else
{
log.Debug("No expired hosted identities found.");
}
}
catch (Exception e)
{
log.Error("Exception occurred: {0}", e.ToString());
}
unitOfWork.ReleaseLock(lockObject);
}
if (imagesToDelete.Count > 0)
{
ImageManager imageManager = (ImageManager)Base.ComponentDictionary[ImageManager.ComponentName];
foreach (byte[] hash in imagesToDelete)
{
imageManager.RemoveImageReference(hash);
}
}
log.Trace("(-)");
}
/// <summary>
/// Checks if any of the follower servers need refresh. If so, a neighborhood action is created.
/// <para>This function also checks if there are unprocessed refresh neighborhood actions
/// and if there are 3 such requests already, the follower is deleted as it is considered as unresponsive for too long.</para>
/// </summary>
public async Task CheckFollowersRefreshAsync()
{
log.Trace("()");
// If a follower server's LastRefreshTime is lower than this limit, it should be refreshed.
DateTime limitLastRefreshTime = DateTime.UtcNow.AddSeconds(-Config.Configuration.FollowerRefreshTimeSeconds);
List <byte[]> followersToDeleteIds = new List <byte[]>();
using (UnitOfWork unitOfWork = new UnitOfWork())
{
DatabaseLock[] lockObjects = new DatabaseLock[] { UnitOfWork.FollowerLock, UnitOfWork.NeighborhoodActionLock };
await unitOfWork.AcquireLockAsync(lockObjects);
try
{
List <Follower> followersToRefresh = (await unitOfWork.FollowerRepository.GetAsync(f => f.LastRefreshTime < limitLastRefreshTime, null, true)).ToList();
if (followersToRefresh.Count > 0)
{
bool saveDb = false;
int actionsInserted = 0;
log.Debug("There are {0} followers that need refresh.", followersToRefresh.Count);
foreach (Follower follower in followersToRefresh)
{
int unprocessedRefreshProfileActions = await unitOfWork.NeighborhoodActionRepository.CountAsync(a => (a.ServerId == follower.NetworkId) && (a.Type == NeighborhoodActionType.RefreshNeighborStatus));
if (unprocessedRefreshProfileActions < 3)
{
NeighborhoodAction action = new NeighborhoodAction()
{
ServerId = follower.NetworkId,
Type = NeighborhoodActionType.RefreshNeighborStatus,
Timestamp = DateTime.UtcNow,
ExecuteAfter = DateTime.UtcNow,
TargetIdentityId = null,
AdditionalData = null
};
await unitOfWork.NeighborhoodActionRepository.InsertAsync(action);
log.Debug("Refresh neighborhood action for follower ID '{0}' will be inserted to the database.", follower.NetworkId.ToHex());
saveDb = true;
actionsInserted++;
}
else
{
log.Debug("There are {0} unprocessed RefreshNeighborStatus neighborhood actions for follower ID '{1}'. Follower will be deleted.", unprocessedRefreshProfileActions, follower.NetworkId.ToHex());
followersToDeleteIds.Add(follower.NetworkId);
}
}
if (saveDb)
{
await unitOfWork.SaveThrowAsync();
log.Debug("{0} new neighborhood actions saved to the database.", actionsInserted);
}
}
else
{
log.Debug("No followers need refresh now.");
}
}
catch (Exception e)
{
log.Error("Exception occurred: {0}", e.ToString());
}
unitOfWork.ReleaseLock(lockObjects);
if (followersToDeleteIds.Count > 0)
{
log.Debug("There are {0} followers to be deleted.", followersToDeleteIds.Count);
foreach (byte[] followerToDeleteId in followersToDeleteIds)
{
Iop.Shared.Status status = unitOfWork.FollowerRepository.DeleteFollowerAsync(followerToDeleteId).Result;
if (status == Iop.Shared.Status.Ok)
{
log.Debug("Follower ID '{0}' deleted.", followerToDeleteId.ToHex());
}
else
{
log.Warn("Unable to delete follower ID '{0}', error code {1}.", followerToDeleteId.ToHex(), status);
}
}
}
else
{
log.Debug("No followers to delete now.");
}
}
log.Trace("(-)");
}
