public List <UpdateDefinition <BsonDocument> > BuildUpdatesForSave(
UpdateDefinition <BsonDocument> update, TrackableListTracker <T> tracker, params object[] keyValues)
{
var keyNamespace = DocumentHelper.ToDotPath(keyValues);
// Multiple push-back batching optimization
if (tracker.ChangeList.Count > 1 &&
tracker.ChangeList.All(c => c.Operation == TrackableListOperation.PushBack))
{
var newValues = tracker.ChangeList.Select(c => c.NewValue);
return(new List <UpdateDefinition <BsonDocument> >
{
update == null
? Builders <BsonDocument> .Update.PushEach(keyNamespace, newValues)
: update.PushEach(keyNamespace, newValues)
});
}
// Multiple push-front batching optimization
if (tracker.ChangeList.Count > 1 &&
tracker.ChangeList.All(c => c.Operation == TrackableListOperation.PushFront))
{
var newValues = tracker.ChangeList.Select(c => c.NewValue).Reverse();
return(new List <UpdateDefinition <BsonDocument> >
{
update == null
? Builders <BsonDocument> .Update.PushEach(keyNamespace, newValues, position : 0)
: update.PushEach(keyNamespace, newValues, position: 0)
});
}
// List update can process only one change each time
var updates = new List <UpdateDefinition <BsonDocument> >();
foreach (var change in tracker.ChangeList)
{
switch (change.Operation)
{
case TrackableListOperation.Insert:
updates.Add(update == null
? Builders <BsonDocument> .Update.PushEach(keyNamespace, new[] { change.NewValue }, position: change.Index)
: update.PushEach(keyNamespace, new[] { change.NewValue }, position: change.Index));
update = null;
break;
case TrackableListOperation.Remove:
throw new Exception("Remove operation is not supported!");
case TrackableListOperation.Modify:
updates.Add(update == null
? Builders <BsonDocument> .Update.Set(keyNamespace + "." + change.Index, change.NewValue)
: update.Set(keyNamespace + "." + change.Index, change.NewValue));
break;
case TrackableListOperation.PushFront:
updates.Add(update == null
? Builders <BsonDocument> .Update.PushEach(keyNamespace, new[] { change.NewValue }, position: 0)
: update.PushEach(keyNamespace, new[] { change.NewValue }, position: 0));
break;
case TrackableListOperation.PushBack:
updates.Add(update == null
? Builders <BsonDocument> .Update.Push(keyNamespace, change.NewValue)
: update.Push(keyNamespace, change.NewValue));
break;
case TrackableListOperation.PopFront:
updates.Add(update == null
? Builders <BsonDocument> .Update.PopFirst(keyNamespace)
: update.PopFirst(keyNamespace));
break;
case TrackableListOperation.PopBack:
updates.Add(update == null
? Builders <BsonDocument> .Update.PopLast(keyNamespace)
: update.PopLast(keyNamespace));
break;
}
}
if (update != null)
{
updates.Add(update);
}
return(updates);
}
