Save multiple model at once, in bulk

I know this subject has already been discussed around stackoverflow and other forums, but I cannot find the right way to do it.

I have a model called "post" which contain post information (user, description, etc...). The user receive a few post, reads them and make actions on them. The posts are coming from my api when I request a GET /api/posts/

I also have a model called "post-state" where I save the action of people reading the post: when they like, share, vote, or favourite the post.

export default DS.Model.extend({
    post: belongsTo('post'),
    user: belongsTo('user'),
    liked: attr('boolean', { defaultValue: false }),
    favourited: attr('boolean', { defaultValue: false }),
    voted: attr('boolean', { defaultValue: false }),
    shared: attr('boolean', { defaultValue: false }),
});

I'm looking for a way for my ember application to save my post-state models in a bulk, just the way I received the post in a bulk as well. The post states would be saved with an api call POST /api/post-states/

I've read in a discussion that the best way would be to create a custom adapter, but I'm not sure what to put in it to be able to do that... maybe to create a function saveAllRecords()?

What would be the best solution for me?

Thank you for you help!