To Post a new microblog an ActivityStream entry is POSTed to the appropriate microblog API endpoint. Microblogging requires only a small subset of the ActivityStream data model.
The body of the POST for a microblog is an ActivityEntry object. Note that only the "content" and "attachments" properties in the passed ActivityEntry object are handled by the server - other properties are ignored -
The "content" field is the text of the microblog message. It is a mandatory field.
The "attachments" field is an array of ActivityObject objects.