Postback Received

This callback occurs when the user presses Postback Button. You can use this event to perform certain action or to send a reply.

{
  "event": "postback",
  "timestamp": "2017-03-01T15:49:02.243Z",
  "data": {
    "channel": {
      "id": "6456078759331238786",
      "type": "viber"
    },
    "contact": {
      "id": "6456078781510718339"
    },
    "postback": {
      "payload": "{{PASS_THROUGH_PARAM}}"
    }
  }
}

Parameter	Type	Description
payload	string	Developer-defined data set in Postback Button.