private async Task <Tuple <Tags, IPagedList <PostViewModel> > > GetPostsByTag(string tagName, int page)
{
var query = _postManager.GetQueryable();
var tag = await _tagManager.FindByNameAsync(tagName);
if (tag != null)
{
query = query.Where(t => t.Tags.Any(c => c.TagsId == tag.Id));
}
var result = await GetPosts(query, page);
return(new Tuple <Tags, IPagedList <PostViewModel> >(tag, result));
}