public async Task <IActionResult> GetCommentsForPost([FromQuery] CommentResourceParameters commentResourceParameters, Guid postId)
{
if (!_propertyMapping.ValidMappingExist <CommentOutputDto, Comment>(commentResourceParameters.OrderBy))
{
return(BadRequest());
}
if (!_propertyValidation.HasValidProperties <CommentOutputDto>(commentResourceParameters.Fields))
{
return(BadRequest());
}
var commentsFromRepo = _commentRepository.GetCommentsForPost(postId, commentResourceParameters);
var previousPageLink = commentsFromRepo.HasPrevious ? CreateCommentsUri(commentResourceParameters, UriType.PreviousPage, "GetCommentsForPost") : null;
var nextPageLink = commentsFromRepo.HasNext ? CreateCommentsUri(commentResourceParameters, UriType.NextPage, "GetCommentsForPost") : null;
var metaData = new
{
totalCount = commentsFromRepo.TotalCount,
pageSize = commentsFromRepo.PageSize,
currentPage = commentsFromRepo.CurrentPage,
totalPages = commentsFromRepo.TotalPages,
previousPageLink,
nextPageLink,
};
Response.Headers.Add("Pagination", JsonSerializer.Serialize(metaData));
return(Ok(_mapper.Map <IEnumerable <CommentOutputDto> >(commentsFromRepo).ShapeData(commentResourceParameters.Fields)));
}
private string CreateCommentsUri(CommentResourceParameters commentResourceParameters, UriType uriType, string routeName)
{
switch (uriType)
{
case UriType.PreviousPage:
return(Url.Link(routeName, new
{
pageNumber = commentResourceParameters.PageNumber - 1,
commentResourceParameters.PageSize,
commentResourceParameters.OrderBy,
commentResourceParameters.Fields
}));
case UriType.NextPage:
return(Url.Link(routeName, new
{
pageNumber = commentResourceParameters.PageNumber + 1,
commentResourceParameters.PageSize,
commentResourceParameters.OrderBy,
commentResourceParameters.Fields
}));
default:
return(Url.Link(routeName, new
{
commentResourceParameters.PageNumber,
commentResourceParameters.PageSize,
commentResourceParameters.OrderBy,
commentResourceParameters.Fields
}));
}
}
public PageList <Comment> GetCommentsForPost(Guid postId, CommentResourceParameters commentResourceParameters)
{
if (postId == Guid.Empty)
{
throw new ArgumentNullException(nameof(postId));
}
var collection = _context.Comments as IQueryable <Comment>;
// No SearchingQuery Needed
collection = collection.Include(c => c.Author).Where(c => c.BelongPostId == postId);
if (!string.IsNullOrWhiteSpace(commentResourceParameters.OrderBy))
{
var commentPropertyMappingDictionary = _propertyMapping.GetPropertyMapping <PostOutputDto, Post>();
collection = collection.ApplySort(commentResourceParameters.OrderBy, commentPropertyMappingDictionary);
}
return(PageList <Comment> .Create(collection, commentResourceParameters.PageNumber, commentResourceParameters.PageSize));
}
