/// <summary>
/// Delete one or more entities as a single ACID transaction
/// </summary>
/// <param name="entities"></param>
public void Delete(params IEntity[] entities)
{
Conflicts conflicts = new Conflicts();
if (!CanDelete(entities, conflicts))
{
throw new OptimisticConcurrencyException(conflicts);
}
DoDelete(entities);
}
/// <summary>
/// Update one or more existing entities by replacing if id, type and version match exactly.
/// </summary>
/// <param name="entities"></param>
internal void _Update(params IEntity[] entities)
{
Conflicts conflicts = new Conflicts();
if (!CanUpdate(entities, conflicts))
{
throw new OptimisticConcurrencyException(conflicts);
}
DoUpsert(entities);
}
/// <summary>
/// Throw an exception if any of the keys exist
/// </summary>
private bool CanInsert(IEnumerable <IEntity> entities, Conflicts conflicts = null)
{
conflicts = conflicts ?? new Conflicts();
int numConflicts = conflicts.Inserts.Count;
foreach (var entity in entities)
{
var set = For(entity);
IEntity existing;
if (set.TryGetValue(entity.Id, out existing))
{
conflicts.Inserts.Add(new EntityKey(existing));
}
}
return(numConflicts == conflicts.Inserts.Count);
}
/// <summary>
/// Execute multiple inserts, updates, deletes as a single ACID transaction
/// </summary>
/// <param name="batch"></param>
public void DoExecute(Batch batch)
{
var missingTypes = batch.Types().Except(_entitySets.Keys).ToArray();
if (missingTypes.Any())
{
throw new MissingTypesException(missingTypes);
}
Conflicts conflicts = new Conflicts();
if (!CanExecute(batch, conflicts))
{
throw new OptimisticConcurrencyException(conflicts);
}
DoUpsert(batch.Updates);
DoUpsert(batch.Inserts);
DoDelete(batch.Deletes);
}
private bool CanUpdate(IEnumerable <IEntity> entities, Conflicts conflicts = null)
{
conflicts = conflicts ?? new Conflicts();
int numConflicts = conflicts.Updates.Count;
foreach (var entity in entities)
{
var set = For(entity);
if (!set.ContainsKey(entity.Id))
{
conflicts.Updates.Add(new EntityKey(entity)
{
Version = 0
});
}
else if (set[entity.Id].Version != entity.Version)
{
conflicts.Updates.Add(new EntityKey(set[entity.Id]));
}
}
return(numConflicts == conflicts.Updates.Count);
}
/// <summary>
/// True if every entity exists and has a matching version
/// </summary>
private bool CanDelete(IEnumerable <IEntity> entities, Conflicts conflicts = null)
{
conflicts = conflicts ?? new Conflicts();
int numConflicts = conflicts.Deletes.Count;
foreach (var entity in entities)
{
var set = For(entity);
IEntity existing;
if (!set.TryGetValue(entity.Id, out existing))
{
conflicts.Deletes.Add(new EntityKey(entity)
{
Version = 0
});
}
else if (existing.Version != entity.Version)
{
conflicts.Deletes.Add(new EntityKey(existing));
}
}
return(numConflicts == conflicts.Deletes.Count);
}
public OptimisticConcurrencyException(Conflicts conflicts)
{
Conflicts = conflicts;
}
private bool CanExecute(Batch batch, Conflicts conflicts)
{
return(CanDelete(batch.Deletes, conflicts) &&
CanInsert(batch.Inserts, conflicts) &&
CanUpdate(batch.Updates, conflicts));
}
