/// <summary>
/// Deletes the messages matching the messagefilter passed in
/// </summary>
/// <param name="messageFilter">The message filter.</param>
/// <param name="adapter">The adapter to use for persistence activity.</param>
/// <remarks>The caller has to have started a transaction on the passed in adapter</remarks>
private static async Task DeleteMessagesAsync(IPredicate messageFilter, IDataAccessAdapter adapter)
{
// first delete all audit info for these message. This isn't done by a batch call directly on the db, as this is a targetperentity hierarchy
// which can't be deleted directly into the database in all cases, so we first fetch the entities to delete.
var qf = new QueryFactory();
var q = qf.AuditDataMessageRelated.Where(AuditDataMessageRelatedFields.MessageID.In(qf.Create()
.Select(MessageFields.MessageID)
.Where(messageFilter)));
var messageAudits = await adapter.FetchQueryAsync(q).ConfigureAwait(false);
await adapter.DeleteEntityCollectionAsync(messageAudits).ConfigureAwait(false);
// Threadstatistics are already considered removed.
// delete all attachments for this message. This can be done directly onto the db.
await adapter.DeleteEntitiesDirectlyAsync(typeof(AttachmentEntity),
new RelationPredicateBucket(AttachmentFields.MessageID.In(qf.Create()
.Select(MessageFields.MessageID)
.Where(messageFilter))))
.ConfigureAwait(false);
await adapter.DeleteEntitiesDirectlyAsync(typeof(MessageEntity), new RelationPredicateBucket(messageFilter)).ConfigureAwait(false);
// don't commit the transaction, leave that to the caller.
}
/// <summary>
/// Deletes the threads matching the passed in filter, inside the transaction specified.
/// </summary>
/// <param name="threadFilter">The thread filter.</param>
/// <param name="adapter">The adapter to use in this method, has a live transaction.</param>
private static async Task DeleteThreadsAsync(PredicateExpression threadFilter, IDataAccessAdapter adapter)
{
var qf = new QueryFactory();
// we've to perform a set of actions in a given order to make sure we're not violating FK constraints in the DB.
// First thread statistics for the threads matching the specified threadfilter.
await adapter.DeleteEntitiesDirectlyAsync(typeof(ThreadStatisticsEntity),
new RelationPredicateBucket(ThreadStatisticsFields.ThreadID.In(qf.Thread.Where(threadFilter)
.Select(ThreadFields.ThreadID))))
.ConfigureAwait(false);
// then the messages, which refer to threads
await MessageManager.DeleteAllMessagesInThreadsAsync(threadFilter, adapter);
// delete bookmarks (if exists) of the threads to be deleted
await adapter.DeleteEntitiesDirectlyAsync(typeof(BookmarkEntity),
new RelationPredicateBucket(BookmarkFields.ThreadID.In(qf.Thread.Where(threadFilter)
.Select(ThreadFields.ThreadID))))
.ConfigureAwait(false);
// delete audit info related to this thread. Can't be done directly on the db due to the fact the entities are in a TargetPerEntity hierarchy, which
// can't be deleted directly on the db, so we've to fetch the entities first.
var q = qf.AuditDataThreadRelated.Where(AuditDataThreadRelatedFields.ThreadID.In(qf.Thread.Where(threadFilter).Select(ThreadFields.ThreadID)));
var threadAuditData = await adapter.FetchQueryAsync(q).ConfigureAwait(false);
await adapter.DeleteEntityCollectionAsync(threadAuditData).ConfigureAwait(false);
// delete support queue thread entity for this thread (if any)
await adapter.DeleteEntitiesDirectlyAsync(typeof(SupportQueueThreadEntity),
new RelationPredicateBucket(SupportQueueThreadFields.ThreadID.In(qf.Thread.Where(threadFilter)
.Select(ThreadFields.ThreadID))))
.ConfigureAwait(false);
// delete threadsubscription entities
await adapter.DeleteEntitiesDirectlyAsync(typeof(ThreadSubscriptionEntity),
new RelationPredicateBucket(ThreadSubscriptionFields.ThreadID.In(qf.Thread.Where(threadFilter)
.Select(ThreadFields.ThreadID))))
.ConfigureAwait(false);
// delete the threads themselves, using the filter passed in
await adapter.DeleteEntitiesDirectlyAsync(typeof(ThreadEntity), new RelationPredicateBucket(threadFilter)).ConfigureAwait(false);
// don't commit the transaction, that's up to the caller.
}
