private IQueryable <T> ApplySortToQueryable(CosmosListOptions listOptions, IQueryable <T> filteredQueryable)
{
string orderDirection = listOptions.SortDirection == null || listOptions.SortDirection == SortDirection.ASC ? "OrderBy" : "OrderByDescending";
Type type = typeof(T);
PropertyInfo property = type.GetProperty(listOptions.Sort);
ParameterExpression parameter = Expression.Parameter(type, "p");
MemberExpression propertyAccess = Expression.MakeMemberAccess(parameter, property);
LambdaExpression orderByExp = Expression.Lambda(propertyAccess, parameter);
MethodCallExpression resultExp = Expression.Call(typeof(Queryable), orderDirection, new Type[] { type, property.PropertyType }, filteredQueryable.Expression, Expression.Quote(orderByExp));
return(filteredQueryable.Provider.CreateQuery <T>(resultExp));
}
public async Task <CosmosListPage <T> > GetItemsAsync(IQueryable <T> queryable, QueryRequestOptions requestOptions, CosmosListOptions listOptions)
{
IQueryable <T> filteredQueryable = queryable;
if (listOptions.Search != null && listOptions.SearchOn != null)
{
filteredQueryable = ApplySearchToQueryable(listOptions.Search, listOptions.SearchOn, filteredQueryable);
}
if (listOptions.Filters.Any())
{
filteredQueryable = ApplyFiltersToQueryable(listOptions.Filters, filteredQueryable);
}
if (listOptions.Sort != null)
{
filteredQueryable = ApplySortToQueryable(listOptions, filteredQueryable);
}
QueryDefinition queryDefinition = filteredQueryable.ToQueryDefinition();
FeedIterator <T> queryResultSetIterator = _container.GetItemQueryIterator <T>(queryDefinition, listOptions.ContinuationToken, requestOptions);
List <T> results = new List <T>();
FeedResponse <T> currentResultSet = await queryResultSetIterator.ReadNextAsync();
foreach (T document in currentResultSet)
{
results.Add(document);
}
Response <int> count = await filteredQueryable.CountAsync();
return(new CosmosListPage <T>()
{
Meta = new CosmosMeta()
{
PageSize = (int)requestOptions.MaxItemCount, Total = count.Resource, ContinuationToken = currentResultSet.ContinuationToken
},
Items = results
});
}
