public void run() {
File picture = new File("public/images/test/test.jpg");
Post post = new Post();
post.title = "fake post";
String mimetype = MimeTypes.forFileName(picture.getName()).get();
Blob blob = new Blob(picture, mimetype);
post.picture = blob;
post.insert();
ObjectId id = post.id;
post = Post.find().byId(id);