Inserts EntitySubscription record for user to follow a record. Helpful when you need people to automatically follow a record without logging in on behalf of them.

sfdc-follow-record

// ID of record to follow
String recordId = '<my record id here>';

// Create list of user ids
List<Id> userIdList = new List<Id>();

// add ID of all users to list
userIdList.add( '<user id here>' );

List<EntitySubscription> entitySubList = new List<EntitySubscription>();

for( Id userId : userIdList ) {
    entitySubList.add( new EntitySubscription(
      ParentId = recordId,
      SubscriberId = userId
    ));
}

insert entitySubList;