Bugs in code throwing PHP warnings

Due to the way some of your code is written, there are instances where a PHP Warning is being thrown…

In your getAttachmentStruct method you’re returning either WP_Error or array, but when you make that call, you’re calling it directly inside of an array_merge call … you should be checking if it’s a WP_Error object before trying to merge it into an array

// attachments
            $attachment_content =array();
            foreach($attachments as $attachment){
                $attachment_content = array_merge($attachment_content, self::getAttachmentStruct($attachment));
            }

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