This document explains the JSON payload your webhooks server will receive when a messaging postback webhook event is triggered. A postback webhook event is triggered when a person clicks a postback button, Get Started button, or persistent menu item.

Example Notification

The following is an example of the JSON payload that will be sent to your webhooks server.

{
  "field": "messaging_postbacks",
  "value": {
    "sender": {
      "user_ref": "USER-REF-ID"
    },
    "recipient": {
      "id": "PAGE-ID"
    },
    "timestamp": "1527459824",
    "postback": {
      "mid": "m_MESSAGE-ID",
      "title": "TITLE-FOR-THE-CTA",
      "payload": "USER-DEFINED-PAYLOAD",
      "referral": {
        "ref": "USER-DEFINED-REFERRAL-PARAM",
        "source": "SHORT-URL",
        "type": "OPEN_THREAD"
      }
    }
  }
}

JSON Properties

All JSON properties in a webhook notification are strings.

Property	Description
`postback.mid`	The ID for the message
`postback.payload`	Information defined in the CTA `payload` parameter. This is only included in the webhook notification sent to the app that sent the message to the person.
`postback.referral`	Information about the action the person took to enter a conversation. The `referral` property information is included in the webhook notification only when a person starts a conversation using one of the following then clicking a CTA such as a Get Started button: An m.me Link A Click to Messenger Ad A Messenger QR Code A Welcome Screen
`postback.referral.ref`	The arbitrary data that was originally passed in the `ref` param added to the m.me link. Only alphanumeric characters as well as -, _, and = are supported
`postback.referral.source`	The URL for this referral. For m.me links, the value of source is `“SHORTLINK”`. For referrals from Messenger Conversation Ads, the value of source is `"ADS"`
`postback.referral.type`	The identifier for the referral. For referrals coming from m.me links, it will always be `"OPEN_THREAD"`.
`postback.title`	The title for the Call To Action (CTA) that a person clicked
`recipient.id`	The ID for your Facebook Page
`sender.user_ref`	The ID for the reference for a person who took an action, such as clicked a Get Started, or Persistent Menu item, that sent a message
`timestamp`	The Unix timestamp for date when the webhook notification was sent to your server

messaging_postbacks Webhooks Reference

Example Notification

JSON Properties

See Also