IotHttpsClient_CancelRequestAsync

Cancel an Asynchronous request.

IotHttpsReturnCode_t IotHttpsClient_CancelRequestAsync( IotHttpsRequestHandle_t reqHandle );

This will stop an asynchronous request. When an asynchronous request is stopped it will not proceed to do any of the following: send headers, send body, receive headers, or receive body. This depends on where in the process the request is. For example, if the request is cancelled after sending the headers, then it will not attempt tp send the body. A cancelled return code will be returned to the application.

If this is called before the scheduled asynchronous request actually runs, then request will not be sent. If this is called during any of the asynchronous callbacks, then the library will stop processing the request when the callback returns. This is useful for any error conditions, found during the asynchronous callbacks, where the application wants to stop the rest of the request processing.

If the asynchronous request stops processing, the buffers in IotHttpsRequestInfo_t.userBuffer can be safely freed, modified, or reused, only once IotHttpsClientCallbacks_t.readReadyCallback is invoked.

Example Asynchronous Code

void _applicationDefined_appendHeaderCallback(void * pPrivData, IotHttpsRequestHandle_t reqHandle)
{
     char token[MAX_TOKEN_LENGTH] = { 0 }
     int len = MAX_TOKEN_LENGTH;
     int status = gen_auth_token(token, &len);
     if( status == GEN_TOKEN_FAIL)
     {
         IotHttpsClient_CancelRequestAsync(reqHandle);
     }
     ...
}
 
void _applicationDefined_writeCallback(void * pPrivData, IotHttpsRequestHandle_t reqHandle)
{
     if( application_data_get(writeBuffer, writeBufferLen) == GEN_TOKEN_FAIL)
     {
         IotHttpsClient_CancelRequestAsync(reqHandle);
     }
     ...
}

Parameters

[in]

reqHandle

- Request handle associated with the request.

Returns

One of the following:

• IOT_HTTPS_OK if the request was successfully cancelled.