index_generator.js

var r = new RegExp("system");
db.getCollectionNames().forEach(
  function(c){
	if(!r.test(c)){	
            var indexes = db[c].getIndexes();
            indexes.forEach(function(i){
                var val = i["key"].toSource();
                var trimmedValue = val.substr(1,val.length-2);
                if (trimmedValue !="{_id:1}")
                {
                    print("db."+c+".ensureIndex("+trimmedValue+",{ \"background\":true, \"name\":\"" + i["name"]+"\"});");
                }
               
        });}
	}
);