PatternSuggestion.cs

    public interface IAPIProvider
    {
        void SearchHotels();
        void GetHotelDetails();
        void GetRoomDetails();
        void GetCancellationPolicies();
        void GetExtraGuestChargeDetails();
        void BlockRoom();
        void BookRoom();
        void GetBookingDetails();
        void CancelBooking();
    }
    
    public class ConcreteProviderA : IAPIProvider
    {
        public void BlockRoom()
        {
            //call api
        }

        public void BookRoom()
        {
            //call api
        }

        public void CancelBooking()
        {
            //call api
        }

        public void GetBookingDetails()
        {
            //call api
        }

        public void GetCancellationPolicies()
        {
            //call api
        }

        public void GetExtraGuestChargeDetails()
        {
            //call api
        }

        public void GetHotelDetails()
        {
            //call api
        }

        public void GetRoomDetails()
        {
            //call api
        }

        public void SearchHotels()
        {
            //call api
        }
    }
    
    public class ConcreteProviderB : IAPIProvider
    {
        public void BlockRoom()
        {
            throw new NotImplementedException();
        }

        public void BookRoom()
        {
            //call api
        }

        public void CancelBooking()
        {
            //call api
        }

        public void GetBookingDetails()
        {
            //call api
        }

        public void GetCancellationPolicies()
        {
            throw new NotImplementedException();
        }

        public void GetExtraGuestChargeDetails()
        {
            throw new NotImplementedException();
        }

        public void GetHotelDetails()
        {
            //call api
        }

        public void GetRoomDetails()
        {
            //call api
        }

        public void SearchHotels()
        {
            //call api
        }
    }
    
    /// <summary>
    /// Request from web/mobile will land in this class
    /// </summary>
    public class Client
    {
        public void SearchHotel()
        {
            //get active providers from database & instantiate them
            List<IAPIProvider> providers = new List<IAPIProvider>();            
            foreach(var provider in providers)
            {
                //search hotels from each API provider
                provider.SearchHotels();
            }
        }

        public void GetHotelDetails(int hotelId, int hotelProviderId)
        {
            IAPIProvider provider = null;
            //here, resolve the correct API provider using the input parameters            

            //fetch hotel details from the resolved API provider
            provider.GetHotelDetails();
        }

        //Other methods
    }