All Plivo API requests can be made asynchronous by adding the parameters listed below. When an asynchronous call is made, Plivo will return a generic response with the api_id and the API responses will be sent to the callback URL.

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Arguments

callback_url

The URL notified by the API response is available and to which the response is sent.

callback_method

The method used to notify the callback_url. Defaults to POST.

Response 
{
"message": "async api spawned",
"api_id": "63f0761a-e0ed-11e1-8ea7-12313924e3a6"
}