private static async Task <List <object> > ExecuteWithReplacementsAsync(FieldReplacementProcessor <TItem> replacementProcessor, IQueryable dynamicQueryable, ForEachAsyncDelegate <object> forEachAsync)
{
var dynamicType = dynamicQueryable.ElementType;
var returnObjects = new List <object>();
if (dynamicQueryable.IsInMemory())
{
await ItemQueryHelper.DefaultForEachAsync(dynamicQueryable, AddObjectToList);
}
else
{
await forEachAsync(dynamicQueryable.AsObjects(), AddObjectToList);
}
void AddObjectToList(object dynamicObj)
{
if (dynamicObj != null)
{
replacementProcessor.Replace(dynamicObj, dynamicType);
}
returnObjects.Add(dynamicObj);
}
return(returnObjects);
}
/// <summary>
/// Executes a query that selects only the desired fields from an <see cref="IQueryable{TItem}"/>.
/// </summary>
public async Task <QueriedDataIterator> SelectFieldsOnlyAsync(IQueryable <TItem> items, ForEachAsyncDelegate <object> forEachAsync)
{
Type dynamicType = GetDynamicRuntimeType();
IQueryable dynamicQueryable = GetDynamicQueryable(items, dynamicType);
var replacementProcessor = new FieldReplacementProcessor <TItem>(_fieldReaders);
await replacementProcessor.LoadAllAsync(items);
List <object> dynamicObjects = await ExecuteWithReplacementsAsync(replacementProcessor, dynamicQueryable, forEachAsync);
return(new QueriedDataIterator(dynamicObjects));
}
public async Task <RestItemData> SelectFieldsOnlyAsync(TItem item)
{
Type dynamicType = GetDynamicRuntimeType();
object dynamicObj = GetDynamicObject(item, dynamicType);
if (dynamicObj == null)
{
return(null);
}
IQueryable <TItem> items = new[] { item }.AsQueryable();
var replacementProcessor = new FieldReplacementProcessor <TItem>(_fieldReaders);
await replacementProcessor.LoadAllAsync(items);
replacementProcessor.Replace(dynamicObj, dynamicType);
return(new RestItemData(dynamicObj));
}
