Add Attachment Upload API method

README.md

@@ -95,6 +95,15 @@ Sends a message with the `payload` to the target `recipient`, and calls the call
 * `payload` - Object: The message payload. Should follow the [Send API format](https://developers.facebook.com/docs/messenger-platform/send-api-reference).
 * `callback` - (Optional) Function: Called with `(err, info)` once the request has completed. `err` contains an error, if any, and `info` contains the response from Facebook, usually with the new message's ID.
 
+#### `bot.getAttachmentUploadId(url, is_reusable, type, [callback])`
+
+Sends the media to the Attachment Upload API and calls the callback if the upload is successful, including the `attachment_id`. See [Attachment Upload API](https://developers.facebook.com/docs/messenger-platform/reference/attachment-upload-api).
+
+* `url` - String: Link where can be fetched the media.
+* `is_reusable` - Boolean: Defined if the saved asset will be sendable to other message recipients.
+* `type` - String: The type of media. Can be one of: `image`, `video`, `audio`, `file`.
+* `callback` - (Optional) Function: Called with `(err, info)` once the request has completed. `err` contains an error, if any, and `info` contains the response from Facebook, usually with the media's ID.
+
 #### `bot.sendSenderAction(recipient, senderAction, [callback])`
 
 Sends the sender action `senderAction` to the target `recipient`, and calls the callback if any. Returns a promise.

index.js

@@ -121,6 +121,34 @@ class Bot extends EventEmitter {
       })
   }
 
+  getAttachmentUploadId (url, isReusable, type, cb) {
+    return request({
+      method: 'POST',
+      uri: 'https://graph.facebook.com/v2.6/me/message_attachments',
+      qs: this._getQs(),
+      json: {
+        message: {
+          attachment: {
+            type: type,
+            payload: {
+              is_reusable: isReusable,
+              url: url
+            }
+          }
+        }
+      }
+    })
+      .then(body => {
+        if (body.error) return Promise.reject(body.error)
+        if (!cb) return body
+        cb(null, body)
+      })
+      .catch(err => {
+        if (!cb) return Promise.reject(err)
+        cb(err)
+      })
+  }
+
   setGetStartedButton (payload, cb) {
     return this.setField('get_started', payload, cb)
   }