Line data    Source code

       1              : /*
       2              :  *    Copyright (c) 2024 Project CHIP Authors
       3              :  *    All rights reserved.
       4              :  *
       5              :  *    Licensed under the Apache License, Version 2.0 (the "License");
       6              :  *    you may not use this file except in compliance with the License.
       7              :  *    You may obtain a copy of the License at
       8              :  *
       9              :  *        http://www.apache.org/licenses/LICENSE-2.0
      10              :  *
      11              :  *    Unless required by applicable law or agreed to in writing, software
      12              :  *    distributed under the License is distributed on an "AS IS" BASIS,
      13              :  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
      14              :  *    See the License for the specific language governing permissions and
      15              :  *    limitations under the License.
      16              :  */
      17              : 
      18              : #pragma once
      19              : 
      20              : #include <lib/core/CHIPError.h>
      21              : #include <lib/core/Optional.h>
      22              : 
      23              : namespace chip {
      24              : namespace app {
      25              : 
      26              : /**
      27              :  * @brief Interface for tracking responses to outbound InvokeRequests.
      28              :  *
      29              :  * This interface enables clients to:
      30              :  *   * Verify that received responses correspond to issued InvokeRequests.
      31              :  *   * Detect outstanding responses after the server indicates completion, helpful for identifying response omissions.
      32              :  */
      33              : class PendingResponseTracker
      34              : {
      35              : public:
      36           15 :     virtual ~PendingResponseTracker() = default;
      37              : 
      38              :     /**
      39              :      * Start tracking the given `aCommandRef`
      40              :      *
      41              :      * @return CHIP_ERROR_INVALID_ARGUMENT if `aCommandRef` is already being tracked.
      42              :      */
      43              :     virtual CHIP_ERROR Add(uint16_t aCommandRef) = 0;
      44              : 
      45              :     /**
      46              :      * Removes tracking for the given `aCommandRef`
      47              :      *
      48              :      * @return CHIP_ERROR_KEY_NOT_FOUND if aCommandRef is not currently tracked.
      49              :      */
      50              :     virtual CHIP_ERROR Remove(uint16_t aCommandRef) = 0;
      51              : 
      52              :     /**
      53              :      * Checks if the given `aCommandRef` is being tracked.
      54              :      */
      55              :     virtual bool IsTracked(uint16_t aCommandRef) = 0;
      56              : 
      57              :     /**
      58              :      * Returns the number of pending responses.
      59              :      */
      60              :     virtual size_t Count() = 0;
      61              : 
      62              :     /**
      63              :      * Removes a pending response command reference from the tracker.
      64              :      *
      65              :      * Deletes an element from the tracker (order not guaranteed). This function can be called
      66              :      * repeatedly to remove all tracked pending responses.
      67              :      *
      68              :      * @return NullOptional if the tracker is empty.
      69              :      * @return Optional containing the CommandReference of a removed pending response.
      70              :      */
      71              :     virtual Optional<uint16_t> PopPendingResponse() = 0;
      72              : };
      73              : 
      74              : } // namespace app
      75              : } // namespace chip