example

var saved_options = {};

function getOptions(myOption){
    
    if(saved_options[myOption]){
        var deferred = $q.defer();
        deferred.resolve(saved_options[myOption]);
        return deferred.promise;
    }else{
        return $http({method: 'GET', url:'someUrl'}).then(function(data){
            saved_options[myOption] = data.data;
            return data.data;
        });
    }
    
}