public async Task <PagedResC <TextPostRes> > GetPageDesc(PagedReqC req, long userId)
{
var user = UnitOfWork.AppUsers.GetById(userId);
if (user == null)
{
throw new BusinnessException("Invalid user id: " + userId);
}
// Create filters only if this is a first page request
List <Expression <Func <TextPost, bool> > > filters = null;
var isFirstPageReq = string.IsNullOrWhiteSpace(req.ContinuationToken); // a non-empty token indicates a next page request
if (isFirstPageReq)
{
filters = new List <Expression <Func <TextPost, bool> > >();
// Although incidentally userId is also partition key, this serves as a reference to implement filters with pagination
// Note: Only paths included for indexing in the collection, can be added here as filters.
filters.Add(p => p.CreatedByUserId == userId); // user can see only his posts
// you may add more filters as desired here
}
// Get page
var page = await UnitOfWork.TextPostRepo.GetPageDescendingAsync <long>(req.ContinuationToken, userId, filters);
// Map to specific activities
var resItems = Mapper.Map <IEnumerable <TextPostRes> >(page.Items);
return(new PagedResC <TextPostRes>(resItems, page.ContinuationToken));
}
public async Task <IHttpActionResult> Page(PagedReqC req)
{
var userId = GetUserIdFromContext();
return(Ok(await _postsService.GetPageDesc(req, userId)));
}
