How to automatically change the permissions of a document when is published?

Question

I have a document library with document versions enable on a SharePoint 2013 site. In the library each document have its own independent permissions. Usually the permissions are 2 owners and 3 or more contributors.

After a document is edited and approved it gets published and gets a “major version”. At that point we manually remove the contributor’s permissions and only the owner’s remains. If a new request for change is made we assign new contributors (not necessarily the original ones) manually and the process repeat itself.

We want to implement a way for removing the contributor’s permissions automatically when the document is published and gets a major version.

We have been considering event receivers and workflows but since we don’t have a lot of experience with them we don’t know if one of them is a better option or there is any other way.

So basically the questions is: What is the easier way to automatically change the permissions of a document when is published?

Answer 1

Using EventReceiver you can handle ItemUpdated

public override void ItemUpdated(SPItemEventProperties properties)
{
    base.ItemUpdating(properties);
    if(properties.ListItem.ModerationInformation==SPModerationStatusType.Approved)
    {
        //Remove permission
    }
}