update

app/Transformers/FeedTransformer.php

@@ -32,8 +32,8 @@ class FeedTransformer extends TransformerAbstract {
            // 'follow_status' => $this->getFollowStatus($feed['uid'],$feed['follow_uid']),
             'type' => $feed['type'],
             'relate_id' => $feed['relate_id'],
-            'relate_data' => !empty($feed['relate_data'])?$feed['relate_data']:'',
-            'content' => !empty($feed['content'])?json_decode($feed['content']):'',
+            'relate_data' => !empty($feed['relate_data'])?$feed['relate_data']:null,
+            'content' => !empty($feed['content'])?json_decode($feed['content']):null,
             'created_at' => Carbon::parse($feed['created_at'])->diffForHumans(),
         ];
     }