EventController.before.cs

/// <summary>
/// Returns filtered list of events.
/// </summary>
/// <remarks>Returns filtered list of events according to filter and other parameters\n</remarks>
/// <param name="filter">A string to filter events by. Currently is filtering only event names using StartsWith criteria</param>
/// <param name="eventType">Type of the events to return (local/global). If omitted, return all events</param>
/// <param name="pageNumber">Zero-based page number</param>
/// <param name="recordsPerPage">Records per page</param>
/// <param name="sortField">Field to sort by</param>
/// <param name="sortOrder">Sorting order (asc/desc)</param>
/// <response code="200">An array of events wrapped in success response object</response>
/// <response code="500">Unexpected error</response>
[HttpGet]
[SwaggerOperation("GetEventsList")]
[SwaggerResponse(200, type: typeof(SuccessResponseWithArrayAndCount<MeetingEventDTO>))]
public IActionResult GetEventsList(
    [FromQuery(Name = "filter")] string filter, 
    [FromQuery(Name = "event_type")] string eventType,
    [FromQuery(Name = "page")] int pageNumber,
    [FromQuery(Name = "per_page")] int recordsPerPage = 10,
    [FromQuery(Name = "sort_field")] string sortField = "start_date",
    [FromQuery(Name = "sort_order")] string sortOrder = "asc"
    )
{
    if (string.IsNullOrWhiteSpace(sortOrder))
        sortOrder = "";
    if (!UserUid.HasValue)
        return UnauthorizedWithCodeAndBody(401, ErrorResponse.GenerateInvalidUser("user_uid"));
    if (UserSubscription == null)
        return UnauthorizedWithCodeAndBody(402, ErrorResponse.GenerateSubscriptionExpired(null));
    if (UserSubscription.ExpiresAt < DateTime.Now)
        return UnauthorizedWithCodeAndBody(402, ErrorResponse.GenerateSubscriptionExpired(UserSubscription.ExpiresAt));
    if (!string.IsNullOrWhiteSpace(sortField) && !SortDictionary.ContainsKey(sortField))
        return BadRequest(ErrorResponse.GenerateInvalidParameter(typeof(MeetingEvent), "", "Invalid sort field: " + sortField, "sort_field"));
    if (filter == null)
        filter = string.Empty;
    
    Logger.LogInformation($@"Trying to get all events with names starting with '{filter}'");

    using (var db = GetDatabaseService())
    {
        var eventsWithCategoriesAndOptions = db.EventsTable.Include(eventObj => eventObj.AttendeeCategories).ThenInclude(categoryObj => categoryObj.Options);
        var filteredMeetingEventsCount = ConstructRecordsListQuery(db.EventsTable, eventType, filter, 0, 0, null, true).Count();
        var eventsListQuery = ConstructRecordsListQuery(eventsWithCategoriesAndOptions, eventType, filter, pageNumber, recordsPerPage, SortDictionary[sortField], sortOrder.ToLower() != "desc");
        var meetingEventDtos = eventsListQuery.Select(MeetingEventDTO.From).ToList();
        var responseObj = new SuccessResponseWithArrayAndCount<MeetingEventDTO>()
        {
            Data = meetingEventDtos,
            TotalFilteredRecords = filteredMeetingEventsCount,
        };
        return Ok(responseObj);
    }
}

protected static IQueryable<MeetingEvent> ConstructRecordsListQuery(
            IQueryable<MeetingEvent> dbTable,
            string eventType,
            string filter,
            int pageNumber,
            int pageSize,
            string sortPropertyName,
            bool isAscending
            )
{
    IQueryable<MeetingEvent> queryMeetingEvents = dbTable;
    if (!string.IsNullOrWhiteSpace(eventType))
    {
        queryMeetingEvents = queryMeetingEvents.Where(rec => rec.Type == eventType);
    }
    if (!string.IsNullOrWhiteSpace(filter))
    {
        queryMeetingEvents = queryMeetingEvents.Where(rec => rec.Name.StartsWith(filter));
    }
    if (sortPropertyName != null)
    {
        queryMeetingEvents = queryMeetingEvents.OrderBy(sortPropertyName, isAscending);
    }
    if (pageNumber > 0 && pageSize > 0)
        queryMeetingEvents = queryMeetingEvents.Skip(pageNumber * pageSize);
    if (pageSize > 0)
        queryMeetingEvents = queryMeetingEvents.Take(pageSize);
    return queryMeetingEvents;
}