Reuse Endpoints.

[c-lgrant]

Hello,

Im wondering if the following is possible I want to define multiple end points but have them resolve to the same function for example:

/app/maps/{mapGuid}/start
/app/maps/{mapGuid}/stop

What i want to be able to do is to define one function for both of these then add logic based on the url.

Is this possible ?

Thanks

Conor

[lganzzzo]

Hello @c-lgrant !
Thanks you for the question.

You have to create separate method for your business logic processing, and call it from your endpoint mappings.
Example:

  /**
   * Process request 
   */
  std::shared_ptr<OutgoingResponse> handleRequest(String param, String body) {
    OATPP_ASSERT_HTTP(param && body, Status::CODE_404, "param and body should not be null");
    return createResponse(Status::CODE_200, param + body);
  }

  /**
   * Add endpoint mapping
   */
  ENDPOINT("GET", "endpoint1/{param}", endpoint1, PATH(String, param), BODY_STRING(String, body)) {
    return handleRequest(param, body);
  }

  /**
   * Add endpoint mapping
   */
  ENDPOINT("GET", "endpoint2/{param}", endpoint2, PATH(String, param), BODY_STRING(String, body)) {
    return handleRequest(param, body);
  }

Best Regards,
Leonid

[c-lgrant]

Hello,

So there is no way to made two end points to one function?

In the example above, if the logic was different for each endpoint how could the handleRequest function decide which action to take.

Can you confirm if there is a better way to get the url than performing.

this->m_endpointInfo.find(__FUNCTION__).operator*().second.get()->path 

Thanks

Conor

[lganzzzo]

Hey @c-lgrant

It would be helpful, if you could describe what you are trying to achieve in a bit more details.

From what I can guess, it can be achieved in many different ways.

From the code snippet that you've posted:

this->m_endpointInfo.find(__FUNCTION__).operator*().second.get()->path

I would not recommend to do it this way, as it will be hard to maintain such code in case of endpoint name changed or path of the endpoint changed.

As a simplest example I can propose next:

• Variant one:

  static const int ACTION_START = 0;
  static const int ACTION_STOP = 1;

  /**
   * Process request
   */
  std::shared_ptr<OutgoingResponse> handleRequest(String mapGuid, int action) {
    OATPP_ASSERT_HTTP(mapGuid, Status::CODE_404, "mapGuid should not be null");
    switch(action) {
      case ACTION_START:
        // TODO maps.start;
        break;
      case ACTION_STOP:
        // TODO maps.stop;
        break;
      default: throw std::runtime_error("unknown action");
    }
    return createResponse(Status::CODE_200, "OK");
  }

  /**
   * Add endpoint mapping
   */
  ENDPOINT("GET", "/app/maps/{mapGuid}/start", start, PATH(String, mapGuid)) {
    return handleRequest(mapGuid, ACTION_START);
  }

  /**
   * Add endpoint mapping
   */
  ENDPOINT("GET", "/app/maps/{mapGuid}/stop", stop, PATH(String, mapGuid)) {
    return handleRequest(mapGuid, ACTION_STOP);
  }

• Variant two (better way):
  Move map-related common functionality to Map class.

  /**
   *  Inject map processing component
   */
  OATPP_COMPONENT(std::shared_ptr<Map>, m_map);

  /**
   * Add endpoint mapping
   */
  ENDPOINT("GET", "/app/maps/{mapGuid}/start", start, PATH(String, mapGuid)) {
    m_map->start(mapGuid);
    return createResponse(Status::CODE_200, "started");
  }

  /**
   * Add endpoint mapping
   */
  ENDPOINT("GET", "/app/maps/{mapGuid}/stop", stop, PATH(String, mapGuid)) {
    m_map->stop(mapGuid);
    return createResponse(Status::CODE_200, "stopped");
  }

Best Regards,
Leonid

[lganzzzo]

You may also consider to do it this way:

  ENDPOINT("GET", "/app/maps/{mapGuid}/{action}", map, 
           PATH(String, mapGuid), 
           PATH(String, action)) {

    OATPP_ASSERT_HTTP(action && (action == "start" || action == "stop"), Status::CODE_400, "Invalid Action");

    // do things based on mapGuid and action

    return createResponse(Status::CODE_200, "OK");
  }

Regards,
Leonid