Add a type field to message to distinguish between 'message_received' and 'postback'

lib/Facebook.js

@@ -196,7 +196,8 @@ function Facebookbot(configuration) {
                                 mid: facebook_message.message.mid,
                                 sticker_id: facebook_message.message.sticker_id,
                                 attachments: facebook_message.message.attachments,
-                                quick_reply: facebook_message.message.quick_reply
+                                quick_reply: facebook_message.message.quick_reply,
+                                type: "user_message",
                             };
 
                             facebook_botkit.receiveMessage(bot, message);
@@ -219,6 +220,7 @@ function Facebookbot(configuration) {
                                 user: facebook_message.sender.id,
                                 channel: facebook_message.sender.id,
                                 timestamp: facebook_message.timestamp,
+                                type: "facebook_postback",
                             };
 
                             facebook_botkit.receiveMessage(bot, message);

readme-facebook.md

@@ -70,7 +70,9 @@ All incoming events will contain the fields `user` and `channel`, both of which
 
 `message_received` events will also contain either a `text` field or an `attachment` field.
 
-`facebook_postback` events will contain a `payload` field.
+`facebook_postback` events will contain a `payload` field. 
+
+Notice also that `facebook_postback` events trigger the `message_received` event as well. That is why messages will have the `type` field as well. When the message is directly from the user (i.e. onlye `message_received` event) `type` will be set to `"user_message"` and when the message is originated in a `facebook_postback` then `type` will be set to `facebook_postback`.
 
 More information about the data found in these fields can be found [here](https://developers.facebook.com/docs/messenger-platform/webhook-reference).